Based on the nonequilibrium plasma dynamics of air discharge, a dynamic model of zero-dimensional plasma is established by combining the component density equation, the Boltzmann equation, and the energy transfer equa...Based on the nonequilibrium plasma dynamics of air discharge, a dynamic model of zero-dimensional plasma is established by combining the component density equation, the Boltzmann equation, and the energy transfer equation. The evolution properties of nanosecond pulse discharge （NPD） plasma under different air pressures are calculated. The results show that the air pressure has significant impacts on the NPD products and the peak values of particle number density for particles such as O atoms, 03 molecules, N2（A3） molecules in excited states, and NO molecules. It increases at first and then decreases with the increase of air pressure. On the other hand, the peak values of particle number density for N2（B3） and N2（C3） molecules in excited states are only slightly affected by the air pressure.展开更多
Through the simulation of explicit dynamic analysis software LS-DYNA,made an analysis to the particle velocity and the stress distribution of surrounding rock when the explosives blasting.Explicated the mechanical cha...Through the simulation of explicit dynamic analysis software LS-DYNA,made an analysis to the particle velocity and the stress distribution of surrounding rock when the explosives blasting.Explicated the mechanical character of surrounding rock in the foun- dation pit blasting,provided a basis to set of blasting parameters and optimized the blast- ing construction.展开更多
The aroma of peach fruit is predominantly determined by the accumulation of γ-decalactone and ester compounds.A previous study showed that the biosynthesis of these aroma compounds in peach fruit is catalyzed by PpAA...The aroma of peach fruit is predominantly determined by the accumulation of γ-decalactone and ester compounds.A previous study showed that the biosynthesis of these aroma compounds in peach fruit is catalyzed by PpAAT1,an alcohol acyltransferase.In this work,we investigated the key active site residues responsible for γ-decalactone and ester biosynthesis.A total of 14 candidate amino acid residues possibly involved in internal esterification and 9 candidate amino acid residues possibly involved in esterification of PpAAT1 were assessed via site-directed mutagenesis.Analyses of the in vitro enzyme activities of PpAAT1 and its site-directed mutant proteins(PpAAT1-SMs)with different amino acid residue mutations as well as the contents of γ-decalactone in transgenic tobacco leaves and peach fruits transiently expressing PpAAT1 and PpAAT1-SMs revealed that site-directed mutation of H165 in the conserved HxxxD motif led to lost enzymatic activity of PpAAT1 in both internal esterification and its reactions,whereas mutation of the key amino acid residue D376 led to the total loss ofγ-decalactone biosynthesis activity of PpAAT1.Mutations of 9 and 7 other amino acid residues also dramatically affected the enzymatic activity of PpAAT1 in the internal esterification and esterification reactions,respectively.Our findings provide a biochemical foundation for the mechanical biosynthesis ofγ-decalactone and ester compounds catalyzed by PpAAT1 in peach fruits,which could be used to guide the molecular breeding of new peach species with more favorable aromas for consumers.展开更多
Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR...Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR)family,comprising highly conserved ligand-gated ion channels,regulates plant growth and development in response to stress.In this study,11 members of the VvGLR gene family in grapes were identified using whole-genome sequence analysis.Bioinformatic methods were employed to analyze the basic physical and chemical properties,phylogenetic trees,conserved domains,motifs,expression patterns,and evolutionary relationships.Phylogenetic and collinear analyses revealed that the VvGLRs were divided into three subgroups,showing the high conservation of the grape GLR family.These members exhibited 2 glutamate receptor binding regions(GABAb and GluR)and 3-4 transmembrane regions(M1,M2,M3,and M4).Real-time quantitative PCR analysis demonstrated the sensitivity of all VvGLRs to low temperature and salt stress.Subsequent localization studies in Nicotiana tabacum verified that VvGLR3.1 and VvGLR3.2 proteins were located on the cell membrane and cell nucleus.Additionally,yeast transformation experiments confirmed the functionality of VvGLR3.1 and VvGLR3.2 in response to low temperature and salt stress.Thesefindings highlight the significant role of the GLR family,a highly conserved group of ion channels,in enhancing grape stress resistance.This study offers new insights into the grape GLR gene family,providing fundamental knowledge for further functional analysis and breeding of stress-resistant grapevines.展开更多
Potassium(K+)is an essential macronutrient for plants to maintain normal growth and development.Shaker-like K+channels and HAK/KUP/KT transporters are critical components in the K+acquisition and translocation.In this...Potassium(K+)is an essential macronutrient for plants to maintain normal growth and development.Shaker-like K+channels and HAK/KUP/KT transporters are critical components in the K+acquisition and translocation.In this study,we identified 9 Shaker-like K+channel(VvK)and 18 HAK/KUP/KT transporter(VvKUP)genes in grape,which were renamed according to their distributions in the genome and relative linear orders among the distinct chromosomes.Similar structure organizations were found within each group according to the exon/intron structure and protein motif analysis.Chromosomal distribution analysis showed that 9 VvK genes and 18 VvKUP genes were unevenly distributed on 7 or 10 putative grape chromosomes.Three pairs of tandem duplicated genes and one pair of segmental duplicated genes were observed in the expansion of the grape VvKUP genes.Gene expression omnibus(GEO)data analysis showed that VvK and VvKUP genes were expressed differentially in distinct tissues.Various cis-acting regulatory elements pertinent to phytohormone responses and abiotic stresses,including K+deficiency response and drought stress,were detected in the promoter region of VvK and VvKUP genes.This study provides valuable information for further functional studies of VvK and VvKUP genes,and lays a foundation to explore K+uptake and utilization in fruit trees.展开更多
With regard to the bounded linear continuous-time system,a universal chaotic anti-controlling method was presented on the basis of tracking control.A tracking controller is designed to such an extent that it can track...With regard to the bounded linear continuous-time system,a universal chaotic anti-controlling method was presented on the basis of tracking control.A tracking controller is designed to such an extent that it can track any chaotic reference input,thus making it possible to chaotify the linear system.The controller is identical in structure for different controlled linear systems.Computer simulations proved the effectiveness of the proposed method.展开更多
The connection between blasting cost and comprehensive cost is the main concern.Some blasting effect factors (such as unit explosive consumption,uniformity of blockness,shape and porosity of blasting heap),which had a...The connection between blasting cost and comprehensive cost is the main concern.Some blasting effect factors (such as unit explosive consumption,uniformity of blockness,shape and porosity of blasting heap),which had an influence on electric shove loading efficiency,were analyzed.In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward.At the same time,the hole-by-hole blasting is effective technology to improve blasting effect.展开更多
Calcium(Ca^(2+))plays a pivotal role in various signal transduction pathways.Calcineurin B-like proteins(CBLs)are a unique group of Ca^(2+)sensors that decode Ca^(2+)signals by activating the plant specific protein ki...Calcium(Ca^(2+))plays a pivotal role in various signal transduction pathways.Calcineurin B-like proteins(CBLs)are a unique group of Ca^(2+)sensors that decode Ca^(2+)signals by activating the plant specific protein kinase known as the CBL-interacting protein kinase(CIPK).In plants,the CBL-CIPK signaling network regulates multiple signals in response to different extracellular cues including abiotic stress.However,the genome wide annotation and expression patterns of CBLs and CIPKs in woody cutting flower plants are still unclear.In this study,a total number of 7 CBLs(RcCBLs)and 17 CIPKs(RcCIPKs)genes,divided into four and five subfamilies,respectively,were identified from the rose genome.All RcCBLs possess a classic elongation factor-hand(EF-hand)domain,while all RcCIPKs possess both the classic kinase and NAF domains.Most RcCBLs were predicted to be plasma membrane localized,whereas most RcCIPKs were predicted to be cytoplasmic localized.Synteny analysis showed that one RcCBL gene pair and five RcCIPK gene pairs have gone through whole genome duplication events.Promoter cis-element prediction assays indicated that RcCBLs and RcCIPKs could function in different abiotic stress responses in rose plants.Further quantitative real-time PCR analysis demonstrated that RcCBLs and RcCIPKs were expressed in different organs with overlapped but distinct patterns in response to various abiotic stresses.The findings in this work will provide fundamental information and gene resources for further functional research on RcCBLs and RcCIPKs.展开更多
Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport deriv...Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport derived from the green pear‘Zaosu’.A new genetic map was constructed from a population derived from the cross of‘Yuluxiang’and‘Hongzaosu’,from which PpBBX24 was identified as a crucial gene controlling anthocyanin accumulation.Genetic and phylogenetic evidences revealed that PpBBX24 is a repressor of anthocyanin biosynthesis in pear.A 14 bp deletion was detected in the third exon of PpBBX24 in‘Hongzaosu’,resulting in premature termination of protein translation.The truncated PpBBX24 protein was a positive regulator of anthocyanin biosynthesis by activating the transcription of PpCHS and PpUFGT.Three independent variations in the BBX24 coding region that led to premature termination of translation were detected in other pear bud sports and the progeny of a bud sport that all accumulate anthocyanins.The genome of‘Hongzaosu’was assembled using both long-read and short-read sequences.By combining genomic and transcriptomic data,allele-specific expression of PpMYB110a was observed in the fruit skin of‘Hongzaosu',which was likely caused by a large variation in the promoter.This work enhances understanding of coloration in red pears and provides a novel genomic resource for further studies on‘Hongzaosu’pear.展开更多
A study is conducted on a new airworthiness compliance verification method based on pilot-aircraft-environment complex system simulation. Verification scenarios are established by ＂block diagram＂ method based on air...A study is conducted on a new airworthiness compliance verification method based on pilot-aircraft-environment complex system simulation. Verification scenarios are established by ＂block diagram＂ method based on airworthiness criteria. A pi- lot-aircraft-environment complex model is set up and a virtual flight testing method based on connection of MATLAB/Simulink and Flightgear is proposed. Special researches are conducted on the modeling of pilot manipulation stochastic parameters and manipulation in critical situation. Unfavorable flight factors of certain scenario are analyzed, and reliability modeling of impor- tant system is researched. A distribution function of small probability event and the theory on risk probability measurement are studied. Nonlinear function is used to depict the relationship between the cumulative probability and the extremum of the critical parameter. A synthetic evaluation model is set up, modified genetic algorithm （MGA） is applied to ascertaining the distribution parameter in the model, and a more reasonable result is obtained. A clause about vehicle control functions （VCFs） verification in MIL-HDBK-516B is selected as an example to validate the practicability of the method.展开更多
The bearing beams and the supporting beams under low velocity impact may be in four different strain stages of deformation depending on the impact intensity and beam structure strength.Based on the different judging c...The bearing beams and the supporting beams under low velocity impact may be in four different strain stages of deformation depending on the impact intensity and beam structure strength.Based on the different judging conditions of deformation stages,the corresponding calculation models are proposed,the calculation formulae for the determination of the impact force and the beam's lateral displacement are obtained.Calculation shows that the beam's total deflection is small when the flexibility of the supporting component is high and the effect of diminishing deflection disappears almost when the stiffness of the supporting component is high.展开更多
A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ...A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ice accretion on aircraft dynamics, and a pilot model is also involved. In order to investigate icing severity under different icing conditions, support vector regression is applied in establishing relationship between aircraft icing parameter and weather conditions. Considering the characteristics of aircraft icing accidents, a risk probability assessment model optimized by the particle swarm method is developed to measure the safety level. In particular, angle of attack is chosen as a critical parameter in this method. Results presented in the paper for a series of simulation show that this method captures the basic effects of atmospheric icing conditions on flight safety, which may provide an important theoretical reference for icing accidents avoidance.展开更多
Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture ...Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture were first examined fromfracture surface morphology to correlate with the macroscopic fracture behavior andstress state. It is found that specimen thickness has a strong influence on mixed modefracture. As thickness varies from thin to thick the macroscopic fracture surfacesappear the characteristics of plane stress state (2mm, 4mm--thick specimen), three--dimensional stress state (8mm--thick specimens), and plane strain state (14mm--thickspecimens), respectively. The specimens of all kinds of thicknesses are typical of ten-sile type failure under mode Ⅰ loading condition and shear type failure under mode Ⅱloading condition. Two distinct features coexist on the fracture surfaces under mixedmode loading conditions, and the corresponding proportion varies with loading mix-ity. Void--growth processes are the failure mechanism in both predominately tensile-and shears--type fractures. The size and depth of dimples on the fracture surface varygreatly with thickness. Therefore, it is extraordinary necessary to take into accountthe thickness effect when a mixed mode fracture criterion is being established.展开更多
In the coexisted world of 3G,4G,5G and many other specialized wireless communication systems,billions of connections could be existing for various information transmission types.Unluckily,data show that the increase o...In the coexisted world of 3G,4G,5G and many other specialized wireless communication systems,billions of connections could be existing for various information transmission types.Unluckily,data show that the increase of network capacity is heavily more than the increase of the network energy efficiency in recent years,which could lead to more energy consumption per transmitted bit in the future network.As basic units in mobile communication systems,microwave/RF components and modules play key roles展开更多
Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a missile.The hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo ...Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a missile.The hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo method is applied to generate missile detonation location according to its distribution rule.In addition,based on the analysis of fragment trajectory and critical components,the intersection point of these two is determined.Then the kill probability of critical component to a fragment can be calculated,and the aircraft survivability to a missile is obtained accordingly.Finally,the feasibility of the proposed method is demonstrated.Simulation results show that this method captures the basic effects of missile detonation locations on aircraft survivability,which may provide an effective reference to aircraft survivability research.展开更多
Seven in absentia(SINA)family proteins play a central role in plant growth,development and resistance to abiotic stress.However,their biological function in plant response to cold stress is still largely unknown.In th...Seven in absentia(SINA)family proteins play a central role in plant growth,development and resistance to abiotic stress.However,their biological function in plant response to cold stress is still largely unknown.In this work,a seven in absentia gene IbSINA5 was isolated from sweet potato.Quantitative real-time polymerase chain reaction(qRT-PCR)analyses demonstrated that IbSINA5 was ubiquitously expressed in various tissues and organs of sweet potato,with a predominant expression in fibrous roots,and was remarkably induced by cold,drought and salt stresses.Subcellular localization assays revealed that IbSINA5-GFP fusion protein was mainly localized in cytoplasm and nucleus.Overexpression of IbSINA5 in sweet potato led to dramatically improved resistance to cold stress in transgenic plants,which was associated with the up-regulated expression of IbCOR(cold-regulated)genes,increased proline production,and decreased malondialdehyde(MDA)and H2O2 accumulation in the leaves of transgenic plants.Furthermore,transient expression of IbCBF3,a C-repeat binding factor(CBF)gene,in the leaf protoplasts of wild type sweet potato plants up-regulated the expression of both IbSINA5 and IbCOR genes.Our results suggest that IbSINA5 could function as a positive regulator in the cold signaling pathway through a CBF-SINA-COR mediated module in sweet potato,and have a great potential to be used as a candidate gene for the future breeding of new plant species with improved cold resistance.展开更多
With the continuous enrichment of mobile communication application scenarios in the future, the traditional macro-cellular-based mobile communication network architecture will be difficult to meet the explosive growth...With the continuous enrichment of mobile communication application scenarios in the future, the traditional macro-cellular-based mobile communication network architecture will be difficult to meet the explosive growth in demand for communications services.展开更多
This article, in order to improve the assembly of the high-pressure spool, presents an assembly variation identification method achieved by response surface method （RSM）-based model updating using IV-optimal designs...This article, in order to improve the assembly of the high-pressure spool, presents an assembly variation identification method achieved by response surface method （RSM）-based model updating using IV-optimal designs. The method involves screening out non-relevant assembly parameters using IV-optimal designs and the preload of the joints is chosen as the input features and modal frequency is the only response feature. Emphasis is placed on the construction of response surface models including the interactions between the bolted joints by which the non-linear relationship between the assembly variation caused by the changes ofpreload and the output frequency variation is established. By achieving an optimal process of selected variables in the model, assembly variation can be identified. With a case study of the laboratory bolted disks as an example, the proposed method is verified and it gives enough accuracy in variation identification. It has been observed that the first-order response surface models considering the interactions between the bolted joints based on the IV-optimal criterion are adequate for assembly purposes.展开更多
Low temperature is one of the adversities threatening the growth and development and reduces the yield of rubber trees.However,molecular mechanisms toward rubber trees in response to low temperature are largely unclea...Low temperature is one of the adversities threatening the growth and development and reduces the yield of rubber trees.However,molecular mechanisms toward rubber trees in response to low temperature are largely unclear.In this study,7,159 and 7,600 differentially expressed genes(DEGs)were identified in‘Reyan 73397’rubber trees.Through GO analysis,the catalytic activity was the representative of the GO term in the only DEGs at the two studied temperatures(room temperature and 4°C,respectively),while KEGG analysis showed that carbon metabolism was the most important grouping under the comparison of these two temperatures.In addition,expression of 9 members of transcription factor MYB family genes were further verified by qRT-PCR,and MYB family genes may play important roles in the regulation of rubber trees under low temperature stress.This study provided a theoretical foundation for(1)revealing the molecular mechanisms of rubber trees in response to low temperature and(2)breeding of tolerant varieties of rubber trees.展开更多
Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultiva...Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultivated tobacco and tomato cultivars are susceptible to TMV and there is no effective strategy to control this virus.Cross-protection can be a safe and environmentally friendly strategy to prevent viral diseases.However,stable attenuated TMV mutants are scarce.In this study,we found that the substitutions in the replicase p126,arginine at position 196(R^(196))with aspartic acid(D),glutamic acid at position 614(E^(614))with glycine(G),serine at position 643(S^(643))with phenylalanine(F),or D at position 730(D^(730))with S,significantly reduced the virulence and replication of TMV.However,only the mutation of S^(643) to F reduced the RNA silencing suppression activity of TMV p126.A double-mutant TMV-E614G-S643F induced no visible symptom and was genetically stable through six successive passages in tobacco plants.Furthermore,our results showed that TMV-E614G-S643F double-mutant could provide effective protection against the wild-type TMV infection in tobacco and tomato plants.This study reports a promising mild mutant for cross-protection to control TMV in tobacco and tomato plants.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 51106179 and 51276196)
文摘Based on the nonequilibrium plasma dynamics of air discharge, a dynamic model of zero-dimensional plasma is established by combining the component density equation, the Boltzmann equation, and the energy transfer equation. The evolution properties of nanosecond pulse discharge （NPD） plasma under different air pressures are calculated. The results show that the air pressure has significant impacts on the NPD products and the peak values of particle number density for particles such as O atoms, 03 molecules, N2（A3） molecules in excited states, and NO molecules. It increases at first and then decreases with the increase of air pressure. On the other hand, the peak values of particle number density for N2（B3） and N2（C3） molecules in excited states are only slightly affected by the air pressure.
文摘Through the simulation of explicit dynamic analysis software LS-DYNA,made an analysis to the particle velocity and the stress distribution of surrounding rock when the explosives blasting.Explicated the mechanical character of surrounding rock in the foun- dation pit blasting,provided a basis to set of blasting parameters and optimized the blast- ing construction.
基金the following grants:the National Key R&D Program of China(2019YFD1000500)the National Key Program on Transgenic Research(2018ZX08020002-003-004)+3 种基金the National Natural Science Foundation of China(31870576 and 31901572)the Key R&D project of Shandong Province(2018GNC110007)the Agricultural Variety Improvement Project of Shandong Province(2019 LZGC009 and 2019 LZGC010)the Natural Science Foundation of Shandong Province(ZR2019PC015).
文摘The aroma of peach fruit is predominantly determined by the accumulation of γ-decalactone and ester compounds.A previous study showed that the biosynthesis of these aroma compounds in peach fruit is catalyzed by PpAAT1,an alcohol acyltransferase.In this work,we investigated the key active site residues responsible for γ-decalactone and ester biosynthesis.A total of 14 candidate amino acid residues possibly involved in internal esterification and 9 candidate amino acid residues possibly involved in esterification of PpAAT1 were assessed via site-directed mutagenesis.Analyses of the in vitro enzyme activities of PpAAT1 and its site-directed mutant proteins(PpAAT1-SMs)with different amino acid residue mutations as well as the contents of γ-decalactone in transgenic tobacco leaves and peach fruits transiently expressing PpAAT1 and PpAAT1-SMs revealed that site-directed mutation of H165 in the conserved HxxxD motif led to lost enzymatic activity of PpAAT1 in both internal esterification and its reactions,whereas mutation of the key amino acid residue D376 led to the total loss ofγ-decalactone biosynthesis activity of PpAAT1.Mutations of 9 and 7 other amino acid residues also dramatically affected the enzymatic activity of PpAAT1 in the internal esterification and esterification reactions,respectively.Our findings provide a biochemical foundation for the mechanical biosynthesis ofγ-decalactone and ester compounds catalyzed by PpAAT1 in peach fruits,which could be used to guide the molecular breeding of new peach species with more favorable aromas for consumers.
基金This research was funded by the Natural Science Foundation of Shandong Province of China(ZR2022MC144).
文摘Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR)family,comprising highly conserved ligand-gated ion channels,regulates plant growth and development in response to stress.In this study,11 members of the VvGLR gene family in grapes were identified using whole-genome sequence analysis.Bioinformatic methods were employed to analyze the basic physical and chemical properties,phylogenetic trees,conserved domains,motifs,expression patterns,and evolutionary relationships.Phylogenetic and collinear analyses revealed that the VvGLRs were divided into three subgroups,showing the high conservation of the grape GLR family.These members exhibited 2 glutamate receptor binding regions(GABAb and GluR)and 3-4 transmembrane regions(M1,M2,M3,and M4).Real-time quantitative PCR analysis demonstrated the sensitivity of all VvGLRs to low temperature and salt stress.Subsequent localization studies in Nicotiana tabacum verified that VvGLR3.1 and VvGLR3.2 proteins were located on the cell membrane and cell nucleus.Additionally,yeast transformation experiments confirmed the functionality of VvGLR3.1 and VvGLR3.2 in response to low temperature and salt stress.Thesefindings highlight the significant role of the GLR family,a highly conserved group of ion channels,in enhancing grape stress resistance.This study offers new insights into the grape GLR gene family,providing fundamental knowledge for further functional analysis and breeding of stress-resistant grapevines.
基金supported from grants of the Shandong Provincial Natural Science Foundation Project(Grant No.ZR2021MC086)and National Science Foundation of China(31601819 and 3151743).
文摘Potassium(K+)is an essential macronutrient for plants to maintain normal growth and development.Shaker-like K+channels and HAK/KUP/KT transporters are critical components in the K+acquisition and translocation.In this study,we identified 9 Shaker-like K+channel(VvK)and 18 HAK/KUP/KT transporter(VvKUP)genes in grape,which were renamed according to their distributions in the genome and relative linear orders among the distinct chromosomes.Similar structure organizations were found within each group according to the exon/intron structure and protein motif analysis.Chromosomal distribution analysis showed that 9 VvK genes and 18 VvKUP genes were unevenly distributed on 7 or 10 putative grape chromosomes.Three pairs of tandem duplicated genes and one pair of segmental duplicated genes were observed in the expansion of the grape VvKUP genes.Gene expression omnibus(GEO)data analysis showed that VvK and VvKUP genes were expressed differentially in distinct tissues.Various cis-acting regulatory elements pertinent to phytohormone responses and abiotic stresses,including K+deficiency response and drought stress,were detected in the promoter region of VvK and VvKUP genes.This study provides valuable information for further functional studies of VvK and VvKUP genes,and lays a foundation to explore K+uptake and utilization in fruit trees.
文摘With regard to the bounded linear continuous-time system,a universal chaotic anti-controlling method was presented on the basis of tracking control.A tracking controller is designed to such an extent that it can track any chaotic reference input,thus making it possible to chaotify the linear system.The controller is identical in structure for different controlled linear systems.Computer simulations proved the effectiveness of the proposed method.
文摘The connection between blasting cost and comprehensive cost is the main concern.Some blasting effect factors (such as unit explosive consumption,uniformity of blockness,shape and porosity of blasting heap),which had an influence on electric shove loading efficiency,were analyzed.In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward.At the same time,the hole-by-hole blasting is effective technology to improve blasting effect.
基金funded by the following grants:the Natural Science Foundation of Shandong Province of China(ZR2021MC169)the Cooperation Project of University and Local Enterprise in Yantai of Shandong Province(2021XDRHXMPT09).
文摘Calcium(Ca^(2+))plays a pivotal role in various signal transduction pathways.Calcineurin B-like proteins(CBLs)are a unique group of Ca^(2+)sensors that decode Ca^(2+)signals by activating the plant specific protein kinase known as the CBL-interacting protein kinase(CIPK).In plants,the CBL-CIPK signaling network regulates multiple signals in response to different extracellular cues including abiotic stress.However,the genome wide annotation and expression patterns of CBLs and CIPKs in woody cutting flower plants are still unclear.In this study,a total number of 7 CBLs(RcCBLs)and 17 CIPKs(RcCIPKs)genes,divided into four and five subfamilies,respectively,were identified from the rose genome.All RcCBLs possess a classic elongation factor-hand(EF-hand)domain,while all RcCIPKs possess both the classic kinase and NAF domains.Most RcCBLs were predicted to be plasma membrane localized,whereas most RcCIPKs were predicted to be cytoplasmic localized.Synteny analysis showed that one RcCBL gene pair and five RcCIPK gene pairs have gone through whole genome duplication events.Promoter cis-element prediction assays indicated that RcCBLs and RcCIPKs could function in different abiotic stress responses in rose plants.Further quantitative real-time PCR analysis demonstrated that RcCBLs and RcCIPKs were expressed in different organs with overlapped but distinct patterns in response to various abiotic stresses.The findings in this work will provide fundamental information and gene resources for further functional research on RcCBLs and RcCIPKs.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(LR22C150001 to SB,LY22C150003 to JN)the Specialized Research Fund for Major Science and Technique of Zhejiang Province of China(2021C02066-5)+1 种基金the National Natural Science Foundation of China(32072545 to YT,32272639 to SB)the China Agriculture Research System of MOF and MARA(CARS-28)and the Yunnan Science and Technology Talent and Platform Program(202205AF150041)。
文摘Genetic variation contributes to the phenotypic diversity of plants.Most red pear cultivars that accumulate anthocyanins originated from somatic variation and are termed as bud sports.‘Hongzaosu’is a bud sport derived from the green pear‘Zaosu’.A new genetic map was constructed from a population derived from the cross of‘Yuluxiang’and‘Hongzaosu’,from which PpBBX24 was identified as a crucial gene controlling anthocyanin accumulation.Genetic and phylogenetic evidences revealed that PpBBX24 is a repressor of anthocyanin biosynthesis in pear.A 14 bp deletion was detected in the third exon of PpBBX24 in‘Hongzaosu’,resulting in premature termination of protein translation.The truncated PpBBX24 protein was a positive regulator of anthocyanin biosynthesis by activating the transcription of PpCHS and PpUFGT.Three independent variations in the BBX24 coding region that led to premature termination of translation were detected in other pear bud sports and the progeny of a bud sport that all accumulate anthocyanins.The genome of‘Hongzaosu’was assembled using both long-read and short-read sequences.By combining genomic and transcriptomic data,allele-specific expression of PpMYB110a was observed in the fruit skin of‘Hongzaosu',which was likely caused by a large variation in the promoter.This work enhances understanding of coloration in red pears and provides a novel genomic resource for further studies on‘Hongzaosu’pear.
基金National Natural Science Foundation of China (60572172, 61074007)
文摘A study is conducted on a new airworthiness compliance verification method based on pilot-aircraft-environment complex system simulation. Verification scenarios are established by ＂block diagram＂ method based on airworthiness criteria. A pi- lot-aircraft-environment complex model is set up and a virtual flight testing method based on connection of MATLAB/Simulink and Flightgear is proposed. Special researches are conducted on the modeling of pilot manipulation stochastic parameters and manipulation in critical situation. Unfavorable flight factors of certain scenario are analyzed, and reliability modeling of impor- tant system is researched. A distribution function of small probability event and the theory on risk probability measurement are studied. Nonlinear function is used to depict the relationship between the cumulative probability and the extremum of the critical parameter. A synthetic evaluation model is set up, modified genetic algorithm （MGA） is applied to ascertaining the distribution parameter in the model, and a more reasonable result is obtained. A clause about vehicle control functions （VCFs） verification in MIL-HDBK-516B is selected as an example to validate the practicability of the method.
基金the National Science Foundation of China(50578158)
文摘The bearing beams and the supporting beams under low velocity impact may be in four different strain stages of deformation depending on the impact intensity and beam structure strength.Based on the different judging conditions of deformation stages,the corresponding calculation models are proposed,the calculation formulae for the determination of the impact force and the beam's lateral displacement are obtained.Calculation shows that the beam's total deflection is small when the flexibility of the supporting component is high and the effect of diminishing deflection disappears almost when the stiffness of the supporting component is high.
文摘A quantitative assessment method is proposed to sense the specific effects of atmospheric icing conditions on flight safety. A six degree-of-freedom computational flight dynamics model is used to study the effects of ice accretion on aircraft dynamics, and a pilot model is also involved. In order to investigate icing severity under different icing conditions, support vector regression is applied in establishing relationship between aircraft icing parameter and weather conditions. Considering the characteristics of aircraft icing accidents, a risk probability assessment model optimized by the particle swarm method is developed to measure the safety level. In particular, angle of attack is chosen as a critical parameter in this method. Results presented in the paper for a series of simulation show that this method captures the basic effects of atmospheric icing conditions on flight safety, which may provide an important theoretical reference for icing accidents avoidance.
文摘Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture were first examined fromfracture surface morphology to correlate with the macroscopic fracture behavior andstress state. It is found that specimen thickness has a strong influence on mixed modefracture. As thickness varies from thin to thick the macroscopic fracture surfacesappear the characteristics of plane stress state (2mm, 4mm--thick specimen), three--dimensional stress state (8mm--thick specimens), and plane strain state (14mm--thickspecimens), respectively. The specimens of all kinds of thicknesses are typical of ten-sile type failure under mode Ⅰ loading condition and shear type failure under mode Ⅱloading condition. Two distinct features coexist on the fracture surfaces under mixedmode loading conditions, and the corresponding proportion varies with loading mix-ity. Void--growth processes are the failure mechanism in both predominately tensile-and shears--type fractures. The size and depth of dimples on the fracture surface varygreatly with thickness. Therefore, it is extraordinary necessary to take into accountthe thickness effect when a mixed mode fracture criterion is being established.
文摘In the coexisted world of 3G,4G,5G and many other specialized wireless communication systems,billions of connections could be existing for various information transmission types.Unluckily,data show that the increase of network capacity is heavily more than the increase of the network energy efficiency in recent years,which could lead to more energy consumption per transmitted bit in the future network.As basic units in mobile communication systems,microwave/RF components and modules play key roles
基金Supported by the National High Technology Research and Development Programme of China(No.2009AA04Z406)the National NaturalScience Foundation of China(No.61172083)
文摘Since missiles are main threat against aircrafts in air war,a model is proposed for calculating the aircraft survivability to a missile.The hit characteristic of aircraft to a missile is analyzed,and then Monte Carlo method is applied to generate missile detonation location according to its distribution rule.In addition,based on the analysis of fragment trajectory and critical components,the intersection point of these two is determined.Then the kill probability of critical component to a fragment can be calculated,and the aircraft survivability to a missile is obtained accordingly.Finally,the feasibility of the proposed method is demonstrated.Simulation results show that this method captures the basic effects of missile detonation locations on aircraft survivability,which may provide an effective reference to aircraft survivability research.
基金This work was jointly supported by the following grants:Agricultural Variety Improvement Project of Shandong Province[Grant Nos.2019LZGC009,2019LZGC010,2020LZGC007]the National Key R&D Program of China[Grant Nos.2018YFD1000500,2019YFD1000500]+4 种基金the National Natural Science Foundation of China[Grant Nos.31870576,31901572,32071733]the Natural Science Foundation of Shandong Province[Grant Nos.ZR2018PH041,ZR2019PC015,ZR2020MC138]the Modern Agricultural Industry Technology System Innovation Team of Shandong Province of China[Grant No.SDAIT-02-05]the Key R&D Program of Shandong Province of China[2019GSF108154]the Science and Technology Development Project in Yantai[Grant No.2018XSCC041].
文摘Seven in absentia(SINA)family proteins play a central role in plant growth,development and resistance to abiotic stress.However,their biological function in plant response to cold stress is still largely unknown.In this work,a seven in absentia gene IbSINA5 was isolated from sweet potato.Quantitative real-time polymerase chain reaction(qRT-PCR)analyses demonstrated that IbSINA5 was ubiquitously expressed in various tissues and organs of sweet potato,with a predominant expression in fibrous roots,and was remarkably induced by cold,drought and salt stresses.Subcellular localization assays revealed that IbSINA5-GFP fusion protein was mainly localized in cytoplasm and nucleus.Overexpression of IbSINA5 in sweet potato led to dramatically improved resistance to cold stress in transgenic plants,which was associated with the up-regulated expression of IbCOR(cold-regulated)genes,increased proline production,and decreased malondialdehyde(MDA)and H2O2 accumulation in the leaves of transgenic plants.Furthermore,transient expression of IbCBF3,a C-repeat binding factor(CBF)gene,in the leaf protoplasts of wild type sweet potato plants up-regulated the expression of both IbSINA5 and IbCOR genes.Our results suggest that IbSINA5 could function as a positive regulator in the cold signaling pathway through a CBF-SINA-COR mediated module in sweet potato,and have a great potential to be used as a candidate gene for the future breeding of new plant species with improved cold resistance.
文摘With the continuous enrichment of mobile communication application scenarios in the future, the traditional macro-cellular-based mobile communication network architecture will be difficult to meet the explosive growth in demand for communications services.
文摘This article, in order to improve the assembly of the high-pressure spool, presents an assembly variation identification method achieved by response surface method （RSM）-based model updating using IV-optimal designs. The method involves screening out non-relevant assembly parameters using IV-optimal designs and the preload of the joints is chosen as the input features and modal frequency is the only response feature. Emphasis is placed on the construction of response surface models including the interactions between the bolted joints by which the non-linear relationship between the assembly variation caused by the changes ofpreload and the output frequency variation is established. By achieving an optimal process of selected variables in the model, assembly variation can be identified. With a case study of the laboratory bolted disks as an example, the proposed method is verified and it gives enough accuracy in variation identification. It has been observed that the first-order response surface models considering the interactions between the bolted joints based on the IV-optimal criterion are adequate for assembly purposes.
基金supported by the following grants:the National Key R&D Program of China(2019YFD1000500)the National Natural Science Foundations of Shandong Province(ZR2020MC138)the Agricultural Variety Improvement Project of Shandong Province(2020LZGC007).
文摘Low temperature is one of the adversities threatening the growth and development and reduces the yield of rubber trees.However,molecular mechanisms toward rubber trees in response to low temperature are largely unclear.In this study,7,159 and 7,600 differentially expressed genes(DEGs)were identified in‘Reyan 73397’rubber trees.Through GO analysis,the catalytic activity was the representative of the GO term in the only DEGs at the two studied temperatures(room temperature and 4°C,respectively),while KEGG analysis showed that carbon metabolism was the most important grouping under the comparison of these two temperatures.In addition,expression of 9 members of transcription factor MYB family genes were further verified by qRT-PCR,and MYB family genes may play important roles in the regulation of rubber trees under low temperature stress.This study provided a theoretical foundation for(1)revealing the molecular mechanisms of rubber trees in response to low temperature and(2)breeding of tolerant varieties of rubber trees.
基金supported by funds from‘Taishan Scholar’Construction Project,China(TS2022-028 and 202101KN275)。
文摘Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultivated tobacco and tomato cultivars are susceptible to TMV and there is no effective strategy to control this virus.Cross-protection can be a safe and environmentally friendly strategy to prevent viral diseases.However,stable attenuated TMV mutants are scarce.In this study,we found that the substitutions in the replicase p126,arginine at position 196(R^(196))with aspartic acid(D),glutamic acid at position 614(E^(614))with glycine(G),serine at position 643(S^(643))with phenylalanine(F),or D at position 730(D^(730))with S,significantly reduced the virulence and replication of TMV.However,only the mutation of S^(643) to F reduced the RNA silencing suppression activity of TMV p126.A double-mutant TMV-E614G-S643F induced no visible symptom and was genetically stable through six successive passages in tobacco plants.Furthermore,our results showed that TMV-E614G-S643F double-mutant could provide effective protection against the wild-type TMV infection in tobacco and tomato plants.This study reports a promising mild mutant for cross-protection to control TMV in tobacco and tomato plants.
