Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At pre...Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.展开更多
The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by se...The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public health.Currently,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central China.In this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different genotypes.Our study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these birds.These viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and kidneys.At the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular level.The antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic clusters.Our research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central China.It also highlights the necessity of enhancing the surveillance of H9N2 AIVs.展开更多
Let{X_(n)}_(n≥0) be a p-type(p≥2)supercritical branching process with immigration and mean matrix M.Suppose that M is positively regular and ρ is the maximal eigenvalue of M with the corresponding left and right ei...Let{X_(n)}_(n≥0) be a p-type(p≥2)supercritical branching process with immigration and mean matrix M.Suppose that M is positively regular and ρ is the maximal eigenvalue of M with the corresponding left and right eigenvectors v and u.Let ρ>1 and Y_(n)=ρ^(-n)[u·X_(n)-ρ^(n+1)-1/ρ-1(u·λ)],where the vector λ denotes the mean immigration rate.In this paper,we will show that Yn is a martingale and converges to an r.v.Y as n→∞.We study the rates of convergence to 0 as n→∞of P_(i)(|l·X_(n+1)/1·X_(n)-l·(X_(n)M)/1·X_(n)|>ε),P_(i)(|l·X_(n)/1·X_(n)-l·υ/1·υ>ε),P(|Y_(n)-Y|>ε) for any ε>0,i=1,…,p,1=(1,…,1)and l∈R^(p),the p-dimensional Euclidean space.It is shown that under certain moment conditions,the first two decay geometrically,while conditionally on the event Y≥α(α>0)supergeometrically.The decay rate of the last probability is always supergeometric under a finite moment generating function assumption.展开更多
A new improved tri-diagonal method was developed for the non-equilibrium stage model of the catalytic distillation by coupling consumptive reaction coefficient.The reactions in the distillation column were divided int...A new improved tri-diagonal method was developed for the non-equilibrium stage model of the catalytic distillation by coupling consumptive reaction coefficient.The reactions in the distillation column were divided into generative reaction and consumptive reac-tion.The non-equilibrium stage model was introduced for the catalytic distillation process of the dimethyl car-bonate(DMC)synthesis by urea methanolysis over solid based catalyst,and the improved tri-diagonal method was used to solve the model equations.Comparison of pre-dicted results with experiment data shows that the mean relative error of the yield of DMC was 3.78%under dif-ferent conditions such as different operating pressures and reaction temperatures.The improved tri-diagonal matrix method could avoid the negative values of the liquid com-positions during the calculations and restrain the fluc-tuation of compositions by slowing down the variations of the values in the iteration.The modeling results show that the improved tri-diagonal method was appropriate for system containing a wide range of boiling point com-ponents and a different rate of reactions.展开更多
The generation and application of replication-competent influenza A virus （IAV） expressing a reporter gene represent a valuable tool to elucidate the mechanism of viral pathogenesis and establish new coun- termeasur...The generation and application of replication-competent influenza A virus （IAV） expressing a reporter gene represent a valuable tool to elucidate the mechanism of viral pathogenesis and establish new coun- termeasures to combat the threat of influenza. Here, replication-competent 1AVs with a neuraminidase （NA） segment harboring a fluorescent reporter protein, Venus, were generated in the background of H5N1, H7N9, and H9N2 influenza viruses, the three subtypes of viruses with imminent pandemic poten- tial. All three reporter viruses maintained virion morphology, replicated with similar or slightly reduced titers relative to their parental viruses, and stably expressed the fluorescent signal for at least two pas- sages in embryonated chicken eggs. As a proof of concept, we demonstrated that these reporter viruses, used in combination with a high-content imaging system, can serve as a convenient and rapid tool for the screening of antivirals and host factors involved in the virus life cycle. Moreover. the reporter viruses demonstrated similar growth properties and tissue tropism as their parental viruses in mice, among which the HTN9 NA-Venus virus could potentially be used in ex vivo studies to better understand H7N9 pathogenesis or to develop novel therapeutics.展开更多
We consider a very general interacting branching process which includes most of the important interacting branching models considered so far. After obtaining some key preliminary results, we first obtain some elegant ...We consider a very general interacting branching process which includes most of the important interacting branching models considered so far. After obtaining some key preliminary results, we first obtain some elegant conditions regarding regularity and uniqueness, Then the extinction vector is obtained which is very easy to be calculated. The mean extinction time and the conditional mean extinction time are revealed.The mean explosion time and the total mean life time of th, processes are also investigated and resolved.展开更多
An insightful understanding of the formation mechanism of process-inherent defects anddeformation is increasingly important for the property evaluation and structural design of ceramicmatrix composites (CMCs). For thi...An insightful understanding of the formation mechanism of process-inherent defects anddeformation is increasingly important for the property evaluation and structural design of ceramicmatrix composites (CMCs). For this purpose, a coupled thermal–diffusive–mechanical modelingapproach was proposed by considering three important phenomena that occur during the pyrolysisprocess for manufacturing CMCs: variations of the physical and mechanical properties of theconstituents, generation and diffusive of pyrolysis gas, and multiple thermal deformations. Thesynergistic effects of these three phenomena on the stress, damage development, microstructuralmorphology, and process deformation of SiC matrix composites were investigated using finiteelement simulations. This new approach was validated by comparing the simulation and experimentalresults. Significant volume shrinkage of the matrix during the polymer-to-ceramic transformationresulted in large tensile stresses and subsequent highly fragmented microstructure in CMCs. Thepyrolysis-gas-induced expansion on the matrix under a damage state may yield a positive processdeformation of CMCs at the macroscale, overcoming the effects of the volume shrinkage of the bulkmatrix at the microscale. The modeling approach is expected to guide high-quality manufacturing ofCMCs and comprehensive studies of structure–processing–property relationships.展开更多
This paper concentrates on considering the down/up crossing property of weighted Markov collision processes. The joint probability generating function of down crossing and up crossing numbers of weighted Markov collis...This paper concentrates on considering the down/up crossing property of weighted Markov collision processes. The joint probability generating function of down crossing and up crossing numbers of weighted Markov collision processes until its extinction are obtained by constructing and studying a related multi-dimensional Markov chain. Hence, the joint probability distribution of down crossing and up crossing numbers and the mean numbers are obtained.展开更多
We consider an MX/M/c queue with catastrophes and state- dependent control at idle time. Properties of the queues which terminate when the servers become idle are first studied. Recurrence, equilibrium distribution, a...We consider an MX/M/c queue with catastrophes and state- dependent control at idle time. Properties of the queues which terminate when the servers become idle are first studied. Recurrence, equilibrium distribution, and equilibrium queue-size structure are studied for the case of resurrection and no catastrophes. All of these properties and the first effective catastrophe occurrence time are then investigated for the case of resurrection and catastrophes. In particular, we obtain the Laplace transform of the transition probability for the absorbing MX/M/c queue.展开更多
High mobility group box-1 protein(HMGB1)is an evolutionarily ancient protein,which,as an important non-histone chromosome-binding protein in organism cells,is involved in a variety of important biological processes,in...High mobility group box-1 protein(HMGB1)is an evolutionarily ancient protein,which,as an important non-histone chromosome-binding protein in organism cells,is involved in a variety of important biological processes,including DNA repair,gene transcription,cellular inflammatory response,and autophagy.In this study,we established an eccentric exercise model to observe the effect of HMGB1 on skeletal muscle autophagy and to investigate the underlying molecular mechanisms.Forty-eight male 8-week-old SD rats were randomly divided into control group(C)and exercise group(E).Group E was subjected to a bout of eccentric exercise on a treadmill and sampled soleus at 0 h,12 h,24 h,48 h,and 72 h post-exercise.The speed of the exercise protocol in this study was 16 m/min,the slope was−16°,and the time was 90 min.The ultrastructural changes of skeletal muscle were observed by transmission electron microscopy.The protein expressions of HMGB1,Beclin1,and LC3 were detected by Western Blot.The co-localizations of Beclin1/Bcl-2,Beclin1/HMGB1,and Beclin1/Vps34 were measured by immunofluorescence.The results show that eccentric exercise leads to abnormal changes in the ultrastructure of skeletal muscle,and the protein levels of Beclin1,LC3-II/LC3-I,and the content of HMGB1 in nuclear and cytoplasm were significantly increased at 24 h post-exercise(P<0.05).The co-localization of Beclin1/Bcl-2 and Beclin1/HMGB1 were increased significantly at 0 h post-exercise and then decreased,while the co-localization of Beclin1/Vps34 showed the highest level at 24 h post-exercise.In conclusion,HMGB1 facilitates the separation of Beclin1 from Bcl-2 and promotes Beclin1 binding to Vps34,which may play an important role in eccentric exercise-induced skeletal muscle autophagy.展开更多
基金supported by the National Natural Science Foundation of China(32202788)the Special Research Fund of Shanxi Agricultural University for High-level Talents,China(2021XG004)+3 种基金the Fund for Shanxi“1331 Project”,China(20211331-13)the Shanxi Province Excellent Doctoral Work Award-Scientific Research Project,China(SXBYKY2021063,SXBYKY2021005,and SXBYKY 2022014)the earmarked fund for Modern Agro-industry Technology Research System of Shanxi Province,China(2023CYJSTX15-13)the Fundamental Research Program of Shanxi Province,China(202103021224156)。
文摘Avian infectious bronchitis(IB)is a highly contagious infectious disease caused by infectious bronchitis virus(IBV),which is prevalent in many countries worldwide and causes serious harm to the poultry industry.At present,many commercial IBV vaccines have been used for the prevention and control of IB;however,IB outbreaks occur frequently.In this study,two new strains of IBV,SX/2106 and SX/2204,were isolated from two flocks which were immunized with IBV H120 vaccine in central China.Phylogenetic and recombination analysis indicated that SX/2106,which was clustered into the GI-19 lineage,may be derived from recombination events of the GI-19 and GI-7 strains and the LDT3-A vaccine.Genetic analysis showed that SX/2204 belongs to the GVI-1 lineage,which may have originated from the recombination of the GI-13 and GVI-1 strains and the H120 vaccine.The virus cross-neutralization test showed that the antigenicity of SX/2106 and SX/2204 was different from H120.Animal experiments found that both SX/2106 and SX/2204 could replicate effectively in the lungs and kidneys of chickens and cause disease and death,and H120 immunization could not provide effective protection against the two IBV isolates.It is noteworthy that the pathogenicity of SX/2204 has significantly increased compared to the GVI-1 strains isolated previously,with a mortality rate up to 60%.Considering the continuous mutation and recombination of the IBV genome to produce new variant strains,it is important to continuously monitor epidemic strains and develop new vaccines for the prevention and control of IBV epidemics.
基金Fundamental Research Program of Shanxi Province,China(202103021224156)National Natural Science Foundation of China(32202788)+5 种基金Special Research Fund of Shanxi Agricultural University for High-level Talents,China(2021XG004)Science and Technology Innovation Program of Shanxi Agricultural University,China(2021BQ78)special fund for Science and Technology Innovation Teams of Shanxi Province,China(202304051001041)?Shanxi Province Excellent Doctoral Work Award-Scientific Research Project,China(SXBYKY2021005,SXBYKY2021063,SXBYKY2022014)the Fund for Shanxi“1331 Project”,China(20211331-13)earmarked fund for Modern Agro-industry Technology Research System of Shanxi Province,China.
文摘The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public health.Currently,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central China.In this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different genotypes.Our study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these birds.These viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and kidneys.At the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular level.The antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic clusters.Our research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central China.It also highlights the necessity of enhancing the surveillance of H9N2 AIVs.
基金Supported by the National Natural Sciences Foundations of China(Grants Nos.11771452,11571372)Sciences Foundations of Hunan(Grants No.2017JJ2328)。
文摘Let{X_(n)}_(n≥0) be a p-type(p≥2)supercritical branching process with immigration and mean matrix M.Suppose that M is positively regular and ρ is the maximal eigenvalue of M with the corresponding left and right eigenvectors v and u.Let ρ>1 and Y_(n)=ρ^(-n)[u·X_(n)-ρ^(n+1)-1/ρ-1(u·λ)],where the vector λ denotes the mean immigration rate.In this paper,we will show that Yn is a martingale and converges to an r.v.Y as n→∞.We study the rates of convergence to 0 as n→∞of P_(i)(|l·X_(n+1)/1·X_(n)-l·(X_(n)M)/1·X_(n)|>ε),P_(i)(|l·X_(n)/1·X_(n)-l·υ/1·υ>ε),P(|Y_(n)-Y|>ε) for any ε>0,i=1,…,p,1=(1,…,1)and l∈R^(p),the p-dimensional Euclidean space.It is shown that under certain moment conditions,the first two decay geometrically,while conditionally on the event Y≥α(α>0)supergeometrically.The decay rate of the last probability is always supergeometric under a finite moment generating function assumption.
基金support from the National Science Key Foundation(Grant No.2006BAC02A08)was acknowledged.
文摘A new improved tri-diagonal method was developed for the non-equilibrium stage model of the catalytic distillation by coupling consumptive reaction coefficient.The reactions in the distillation column were divided into generative reaction and consumptive reac-tion.The non-equilibrium stage model was introduced for the catalytic distillation process of the dimethyl car-bonate(DMC)synthesis by urea methanolysis over solid based catalyst,and the improved tri-diagonal method was used to solve the model equations.Comparison of pre-dicted results with experiment data shows that the mean relative error of the yield of DMC was 3.78%under dif-ferent conditions such as different operating pressures and reaction temperatures.The improved tri-diagonal matrix method could avoid the negative values of the liquid com-positions during the calculations and restrain the fluc-tuation of compositions by slowing down the variations of the values in the iteration.The modeling results show that the improved tri-diagonal method was appropriate for system containing a wide range of boiling point com-ponents and a different rate of reactions.
基金supported by the National Natural Science Foundation of China(31472215,31521005,31422054,31402206)the National Key R&D Program of China(2016YFD0500205)
文摘The generation and application of replication-competent influenza A virus （IAV） expressing a reporter gene represent a valuable tool to elucidate the mechanism of viral pathogenesis and establish new coun- termeasures to combat the threat of influenza. Here, replication-competent 1AVs with a neuraminidase （NA） segment harboring a fluorescent reporter protein, Venus, were generated in the background of H5N1, H7N9, and H9N2 influenza viruses, the three subtypes of viruses with imminent pandemic poten- tial. All three reporter viruses maintained virion morphology, replicated with similar or slightly reduced titers relative to their parental viruses, and stably expressed the fluorescent signal for at least two pas- sages in embryonated chicken eggs. As a proof of concept, we demonstrated that these reporter viruses, used in combination with a high-content imaging system, can serve as a convenient and rapid tool for the screening of antivirals and host factors involved in the virus life cycle. Moreover. the reporter viruses demonstrated similar growth properties and tissue tropism as their parental viruses in mice, among which the HTN9 NA-Venus virus could potentially be used in ex vivo studies to better understand H7N9 pathogenesis or to develop novel therapeutics.
基金supported by National Natural Science Foundation of China (Grant Nos 11371374 and 11571372)Research Fund for the Doctoral Program of Higher Education of China (Grant No 20110162110060)
文摘We consider a very general interacting branching process which includes most of the important interacting branching models considered so far. After obtaining some key preliminary results, we first obtain some elegant conditions regarding regularity and uniqueness, Then the extinction vector is obtained which is very easy to be calculated. The mean extinction time and the conditional mean extinction time are revealed.The mean explosion time and the total mean life time of th, processes are also investigated and resolved.
基金The research is supported in part by the National Key R&D Program of China(No.2021YFF0501800)in part by the National Natural Science Foundation of China(Nos.12272174,12102179,and U22B6009)+1 种基金Natural Science Foundation of Jiangsu Province(No.BK20200409)the High Level Personnel Project of Jiangsu Province(No.JSSCBS20210618).
文摘An insightful understanding of the formation mechanism of process-inherent defects anddeformation is increasingly important for the property evaluation and structural design of ceramicmatrix composites (CMCs). For this purpose, a coupled thermal–diffusive–mechanical modelingapproach was proposed by considering three important phenomena that occur during the pyrolysisprocess for manufacturing CMCs: variations of the physical and mechanical properties of theconstituents, generation and diffusive of pyrolysis gas, and multiple thermal deformations. Thesynergistic effects of these three phenomena on the stress, damage development, microstructuralmorphology, and process deformation of SiC matrix composites were investigated using finiteelement simulations. This new approach was validated by comparing the simulation and experimentalresults. Significant volume shrinkage of the matrix during the polymer-to-ceramic transformationresulted in large tensile stresses and subsequent highly fragmented microstructure in CMCs. Thepyrolysis-gas-induced expansion on the matrix under a damage state may yield a positive processdeformation of CMCs at the macroscale, overcoming the effects of the volume shrinkage of the bulkmatrix at the microscale. The modeling approach is expected to guide high-quality manufacturing ofCMCs and comprehensive studies of structure–processing–property relationships.
基金This work was substantially supported by the National Natural Science Foundation of China(Grant Nos.11771452,11971486)the Natural Science Foundation of Hunan(No.2020JJ4674).
文摘This paper concentrates on considering the down/up crossing property of weighted Markov collision processes. The joint probability generating function of down crossing and up crossing numbers of weighted Markov collision processes until its extinction are obtained by constructing and studying a related multi-dimensional Markov chain. Hence, the joint probability distribution of down crossing and up crossing numbers and the mean numbers are obtained.
基金This work was substantially supported by the National Natural Sciences Foundations of China （Grant Nos. 11371374, 11771452, 11701489, 11571372）, the National Natural Science Foundation of China-Tian Yuan （Grant No. 11626203）, and the Natural Sciences Foundations of Hunan Province （No. 2017JJ2328）.
文摘We consider an MX/M/c queue with catastrophes and state- dependent control at idle time. Properties of the queues which terminate when the servers become idle are first studied. Recurrence, equilibrium distribution, and equilibrium queue-size structure are studied for the case of resurrection and no catastrophes. All of these properties and the first effective catastrophe occurrence time are then investigated for the case of resurrection and catastrophes. In particular, we obtain the Laplace transform of the transition probability for the absorbing MX/M/c queue.
基金the Special Funded Project of the Basic Scientific Research Operation Fee of the Central University(Grant No.2019PT013,Grant No.2018GJ015)the Natural Science Foundation of China(Grant No.31471133).
文摘High mobility group box-1 protein(HMGB1)is an evolutionarily ancient protein,which,as an important non-histone chromosome-binding protein in organism cells,is involved in a variety of important biological processes,including DNA repair,gene transcription,cellular inflammatory response,and autophagy.In this study,we established an eccentric exercise model to observe the effect of HMGB1 on skeletal muscle autophagy and to investigate the underlying molecular mechanisms.Forty-eight male 8-week-old SD rats were randomly divided into control group(C)and exercise group(E).Group E was subjected to a bout of eccentric exercise on a treadmill and sampled soleus at 0 h,12 h,24 h,48 h,and 72 h post-exercise.The speed of the exercise protocol in this study was 16 m/min,the slope was−16°,and the time was 90 min.The ultrastructural changes of skeletal muscle were observed by transmission electron microscopy.The protein expressions of HMGB1,Beclin1,and LC3 were detected by Western Blot.The co-localizations of Beclin1/Bcl-2,Beclin1/HMGB1,and Beclin1/Vps34 were measured by immunofluorescence.The results show that eccentric exercise leads to abnormal changes in the ultrastructure of skeletal muscle,and the protein levels of Beclin1,LC3-II/LC3-I,and the content of HMGB1 in nuclear and cytoplasm were significantly increased at 24 h post-exercise(P<0.05).The co-localization of Beclin1/Bcl-2 and Beclin1/HMGB1 were increased significantly at 0 h post-exercise and then decreased,while the co-localization of Beclin1/Vps34 showed the highest level at 24 h post-exercise.In conclusion,HMGB1 facilitates the separation of Beclin1 from Bcl-2 and promotes Beclin1 binding to Vps34,which may play an important role in eccentric exercise-induced skeletal muscle autophagy.
