Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clost...Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clostridium perfringens and assessed their influence on growth performance and intestinal health in NE-challenged broilers through in vitro and in vivo experiments.Methods The in vitro experiment included 5 treatment groups:the negative control(NC),2μmol/L diclazuril(DZ),30μmol/L usnic acid(UA),90μmol/L tannic acid(TA),and 15μmol/L usnic acid^(+)45μmol/L tannic acid(UTA)groups.The in vivo experiment involved 320 broilers divided into four groups:PC(NE-challenged),SA(500 mg/kg salinomycin premix^(+)NE-challenged),UA(300 mg/kg usnic acid^(+)NE-challenged),and UTA(300 mg/kg usnic acid^(+)500 mg/kg tannic acid^(+)NE-challenged)groups.Results In the in vitro study,the UA,TA,and UTA treatments significantly increased apoptosis in coccidian oocysts and sporozoites,lowered the mitochondrial membrane potential(P<0.05),and disrupted the oocyst structure compared with those in the NC group.UA and TA had inhibitory effects on C.perfringens,with the strongest inhibition observed in the UTA group.The in vivo results demonstrated that the SA group presented significantly improved growth performance on d 13,21,and 28(P<0.05),whereas the UA and UTA groups presented improvements on d 13 and 21(P<0.05).The SA,UA,and UTA treatments reduced the intestinal lesion scores by d 28 and the fecal coccidian oocyst counts from d 19 to 21(P<0.05).Compared with the PC group,the UA and UTA groups presented lower intestinal sIgA levels and CD8^(+)cell percentages(P<0.05),with a trend toward a reduced CD3^(+)cell percentage(P=0.069).The SA,UA,and UTA treatments significantly reduced the serum diamine oxidase activity,crypt depth,and plateletderived growth factor levels in the intestinal mucosa while increasing the villus height to crypt depth ratio and number of goblet cells(P<0.05).The UTA treatment also significantly increased the acetate and butyrate concentrations in the cecum(P<0.05).With respect to the gut microbiota,significant changes inβdiversity in the ileum and cecum were observed in the SA,UA,and UTA groups,indicating that the microbial community compositions differed among the groups.Romboutsia dominated the SA group,Bacillales dominated the UA group,and Lactobacillales and Lachnospirales dominated the UTA group in the ileal microbiota.In the cecal microbiota,Lactobacillus,Butyricicoccus,and Blautia abundances were significantly elevated in the UTA group(P<0.05).Conclusion Usnic acid and tannic acid induce apoptosis in coccidia and sporozoites by lowering the mitochondrial membrane potential.Both usnic acid alone and in combination with tannic acid alleviate NE-induced adverse effects in broilers by modulating intestinal immunity,altering the microbial composition,and improving intestinal barrier function.Compared with usnic acid alone,the combination of usnic acid and tannic acid had superior effects,providing a promising basis for the development of effective feed additive combinations.展开更多
In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variati...In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variations of the Kuroshio Extension(KE)system,including its large-scale variation,oceanic front meridional shift,and mesoscale eddy activity.Results show that in the cold season from the lower to the upper troposphere,the KE large-scale variation significantly weakens the storm track activity over the central North Pacific south of 30°N.The northward shift of the KE front significantly strengthens the storm track activity over the western and central North Pacific south of 40°N,resulting in a southward shift of the NPST.In contrast,the NPST response to KE mesoscale eddy activity is not so significant and relatively shallow,which only shows some significant positive signals near the dateline in the lower and middle troposphere.Furthermore,it is found that baroclinicity and baroclinic energy conversion play an important role in the formation of the NPST response to the KE multi-scale oceanic variations.展开更多
Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person&#...Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person's real emotions and have a wide range of application in public safety and clinical diagnosis.The analysis of facial micro-expressions in video sequences through computer vision is still relatively recent.In this research,a comprehensive review on the topic of spotting and recognition used in micro expression analysis databases and methods,is conducted,and advanced technologies in this area are summarized.In addition,we discuss challenges that remain unresolved alongside future work to be completed in the field of micro-expression analysis.展开更多
The midwinter suppression(MWS) of the North Pacific storm track(NPST) has been an active research topic for decades. Based on the daily-mean NCEP/NCAR reanalysis from 1948 to 2018, this study investigates the MWS-rela...The midwinter suppression(MWS) of the North Pacific storm track(NPST) has been an active research topic for decades. Based on the daily-mean NCEP/NCAR reanalysis from 1948 to 2018, this study investigates the MWS-related atmospheric circulation characteristics in the Northern Hemisphere by regression analysis with respect to a new MWS index, which may shed more light on this difficult issue. The occurrence frequency of the MWS of the upper-tropospheric NPST is more than 0.8 after the mid-1980 s. The MWS is accompanied by significantly positive sea-level pressure anomalies in Eurasia and negative anomalies over the North Pacific, which correspond to a strengthened East Asian winter monsoon. The intensified East Asian trough and atmospheric blocking in the North Pacific as well as the significantly negative low-level air temperature anomalies, lying upstream of the MNPST, are expected to be distinctly associated with the MWS. However, the relationship between the MWS and low-level atmospheric baroclinicity is somewhat puzzling.From the diagnostics of the eddy energy budget, it is identified that the inefficiency of the barotropic energy conversion related to the barotropic governor mechanism does not favor the occurrence of the MWS. In contrast, weakened baroclinic energy conversion, buoyancy conversion, and generation of eddy available potential energy by diabatic heating are conducive to the occurrence of the MWS. In addition, Ural blocking in the upstream region of the MNPST may be another candidate mechanism associated with the MWS.展开更多
Winter rainfall over southern China is usually enhanced when Madden–Julian oscillation(MJO) is active over the Indian Ocean, but it can be weakened under certain conditions. Here, the diversity of MJO impacts on wint...Winter rainfall over southern China is usually enhanced when Madden–Julian oscillation(MJO) is active over the Indian Ocean, but it can be weakened under certain conditions. Here, the diversity of MJO impacts on winter rainfall and its mechanisms are explored by using scenarios of enhanced and suppressed rainfall anomalies over southern China when MJO is active over the Indian Ocean. The combined effects of low-frequency background moisture and intraseasonal winds are the major contributors to the different rainfall anomalies. Anomalous circulation in mid–high latitudes, especially on intraseasonal timescales, is almost opposite in the two scenarios, which can modulate the response of extratropical atmosphere to MJO heating and then induces the different circulations over southern China. In the enhanced scenario, mid–high latitudes of Eurasia and southern China are dominated by positive and negative sea level pressure anomalies, respectively. The southerly over southern China and the South China Sea induced by MJO heating promotes the anomalous moisture convergence and ascending motion over southern China, resulting in the enhanced rainfall. In the suppressed scenario, however, the circulation in mid–high latitudes does not favor rainfall over southern China and leads to the northerly response to MJO heating over southern China, which enhances moisture divergence and weakens rainfall over southern China.展开更多
Epigenetics’flexibility in terms of finer manipulation of genes renders unprecedented levels of refined and diverse evolutionary mechanisms possible.From the epigenetic perspective,the main limitations to improving t...Epigenetics’flexibility in terms of finer manipulation of genes renders unprecedented levels of refined and diverse evolutionary mechanisms possible.From the epigenetic perspective,the main limitations to improving the stability and accuracy of genetic algorithms are as follows:(1)the unchangeable nature of the external environment,which leads to excessive disorders in the changed phenotype after mutation and crossover;(2)the premature convergence due to the limited types of epigenetic operators.In this paper,a probabilistic environmental gradientdriven genetic algorithm(PEGA)considering epigenetic traits is proposed.To enhance the local convergence efficiency and acquire stable local search,a probabilistic environmental gradient(PEG)descent strategy together with a multi-dimensional heterogeneous exponential environmental vector tendentiously generates more offsprings along the gradient in the solution space.Moreover,to balance exploration and exploitation at different evolutionary stages,a variable nucleosome reorganization(VNR)operator is realized by dynamically adjusting the number of genes involved in mutation and crossover.Based on the above-mentioned operators,three epigenetic operators are further introduced to weaken the possible premature problem by enriching genetic diversity.The experimental results on the open Congress on Evolutionary Computation-2017(CEC’17)benchmark over 10-,30-,50-,and 100-dimensional tests indicate that the proposed method outperforms 10 state-of-the-art evolutionary and swarm algorithms in terms of accuracy and stability on comprehensive performance.The ablation analysis demonstrates that for accuracy and stability,the fusion strategy of PEG and VNR are effective on 96.55%of the test functions and can improve the indicators by up to four orders of magnitude.Furthermore,the performance of PEGA on the real-world spacecraft trajectory optimization problem is the best in terms of quality of the solution.展开更多
基金supported by China Agriculture Research System Program(Project No.CARS-41-G04)。
文摘Background Necrotic enteritis(NE)in broiler chickens leads to significant economic losses in poultry production.This study examined the inhibitory effects of usnic acid and tannic acid on coccidia,sporozoite,and Clostridium perfringens and assessed their influence on growth performance and intestinal health in NE-challenged broilers through in vitro and in vivo experiments.Methods The in vitro experiment included 5 treatment groups:the negative control(NC),2μmol/L diclazuril(DZ),30μmol/L usnic acid(UA),90μmol/L tannic acid(TA),and 15μmol/L usnic acid^(+)45μmol/L tannic acid(UTA)groups.The in vivo experiment involved 320 broilers divided into four groups:PC(NE-challenged),SA(500 mg/kg salinomycin premix^(+)NE-challenged),UA(300 mg/kg usnic acid^(+)NE-challenged),and UTA(300 mg/kg usnic acid^(+)500 mg/kg tannic acid^(+)NE-challenged)groups.Results In the in vitro study,the UA,TA,and UTA treatments significantly increased apoptosis in coccidian oocysts and sporozoites,lowered the mitochondrial membrane potential(P<0.05),and disrupted the oocyst structure compared with those in the NC group.UA and TA had inhibitory effects on C.perfringens,with the strongest inhibition observed in the UTA group.The in vivo results demonstrated that the SA group presented significantly improved growth performance on d 13,21,and 28(P<0.05),whereas the UA and UTA groups presented improvements on d 13 and 21(P<0.05).The SA,UA,and UTA treatments reduced the intestinal lesion scores by d 28 and the fecal coccidian oocyst counts from d 19 to 21(P<0.05).Compared with the PC group,the UA and UTA groups presented lower intestinal sIgA levels and CD8^(+)cell percentages(P<0.05),with a trend toward a reduced CD3^(+)cell percentage(P=0.069).The SA,UA,and UTA treatments significantly reduced the serum diamine oxidase activity,crypt depth,and plateletderived growth factor levels in the intestinal mucosa while increasing the villus height to crypt depth ratio and number of goblet cells(P<0.05).The UTA treatment also significantly increased the acetate and butyrate concentrations in the cecum(P<0.05).With respect to the gut microbiota,significant changes inβdiversity in the ileum and cecum were observed in the SA,UA,and UTA groups,indicating that the microbial community compositions differed among the groups.Romboutsia dominated the SA group,Bacillales dominated the UA group,and Lactobacillales and Lachnospirales dominated the UTA group in the ileal microbiota.In the cecal microbiota,Lactobacillus,Butyricicoccus,and Blautia abundances were significantly elevated in the UTA group(P<0.05).Conclusion Usnic acid and tannic acid induce apoptosis in coccidia and sporozoites by lowering the mitochondrial membrane potential.Both usnic acid alone and in combination with tannic acid alleviate NE-induced adverse effects in broilers by modulating intestinal immunity,altering the microbial composition,and improving intestinal barrier function.Compared with usnic acid alone,the combination of usnic acid and tannic acid had superior effects,providing a promising basis for the development of effective feed additive combinations.
基金jointly supported by the National Natural Science Foundation of China (Grant Nos. 42105066, 42088101, 41975066)supported by the China Postdoctoral Science Foundation (2021M701754)+1 种基金the Postdoctoral Research Funding of Jiangsu Province (2021K052A)the Research Project of the National University of Defense Technology (ZK20-45)
文摘In this paper,a statistical method called Generalized Equilibrium Feedback Analysis(GEFA)is used to investigate the responses of the North Pacific Storm Track(NPST)in the cold season to the multi-scale oceanic variations of the Kuroshio Extension(KE)system,including its large-scale variation,oceanic front meridional shift,and mesoscale eddy activity.Results show that in the cold season from the lower to the upper troposphere,the KE large-scale variation significantly weakens the storm track activity over the central North Pacific south of 30°N.The northward shift of the KE front significantly strengthens the storm track activity over the western and central North Pacific south of 40°N,resulting in a southward shift of the NPST.In contrast,the NPST response to KE mesoscale eddy activity is not so significant and relatively shallow,which only shows some significant positive signals near the dateline in the lower and middle troposphere.Furthermore,it is found that baroclinicity and baroclinic energy conversion play an important role in the formation of the NPST response to the KE multi-scale oceanic variations.
文摘Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person's real emotions and have a wide range of application in public safety and clinical diagnosis.The analysis of facial micro-expressions in video sequences through computer vision is still relatively recent.In this research,a comprehensive review on the topic of spotting and recognition used in micro expression analysis databases and methods,is conducted,and advanced technologies in this area are summarized.In addition,we discuss challenges that remain unresolved alongside future work to be completed in the field of micro-expression analysis.
基金supported by the National Key Research and Development Program of China(Grant No.2018YFC1505901)the National Natural Science Foundation of China(Grant Nos.41490642,4160501,and 41520104008)。
文摘The midwinter suppression(MWS) of the North Pacific storm track(NPST) has been an active research topic for decades. Based on the daily-mean NCEP/NCAR reanalysis from 1948 to 2018, this study investigates the MWS-related atmospheric circulation characteristics in the Northern Hemisphere by regression analysis with respect to a new MWS index, which may shed more light on this difficult issue. The occurrence frequency of the MWS of the upper-tropospheric NPST is more than 0.8 after the mid-1980 s. The MWS is accompanied by significantly positive sea-level pressure anomalies in Eurasia and negative anomalies over the North Pacific, which correspond to a strengthened East Asian winter monsoon. The intensified East Asian trough and atmospheric blocking in the North Pacific as well as the significantly negative low-level air temperature anomalies, lying upstream of the MNPST, are expected to be distinctly associated with the MWS. However, the relationship between the MWS and low-level atmospheric baroclinicity is somewhat puzzling.From the diagnostics of the eddy energy budget, it is identified that the inefficiency of the barotropic energy conversion related to the barotropic governor mechanism does not favor the occurrence of the MWS. In contrast, weakened baroclinic energy conversion, buoyancy conversion, and generation of eddy available potential energy by diabatic heating are conducive to the occurrence of the MWS. In addition, Ural blocking in the upstream region of the MNPST may be another candidate mechanism associated with the MWS.
基金the National Key Research and Development Program of China (2018YFA0606203 and 2018YFC1505901)National Natural Science Foundation of China (41520104008, 41922035, 41575062, and 41475070)Key Research Program of Frontier Sciences of Chinese Academy of Sciences (QYZDB-SSW-DQC017)。
文摘Winter rainfall over southern China is usually enhanced when Madden–Julian oscillation(MJO) is active over the Indian Ocean, but it can be weakened under certain conditions. Here, the diversity of MJO impacts on winter rainfall and its mechanisms are explored by using scenarios of enhanced and suppressed rainfall anomalies over southern China when MJO is active over the Indian Ocean. The combined effects of low-frequency background moisture and intraseasonal winds are the major contributors to the different rainfall anomalies. Anomalous circulation in mid–high latitudes, especially on intraseasonal timescales, is almost opposite in the two scenarios, which can modulate the response of extratropical atmosphere to MJO heating and then induces the different circulations over southern China. In the enhanced scenario, mid–high latitudes of Eurasia and southern China are dominated by positive and negative sea level pressure anomalies, respectively. The southerly over southern China and the South China Sea induced by MJO heating promotes the anomalous moisture convergence and ascending motion over southern China, resulting in the enhanced rainfall. In the suppressed scenario, however, the circulation in mid–high latitudes does not favor rainfall over southern China and leads to the northerly response to MJO heating over southern China, which enhances moisture divergence and weakens rainfall over southern China.
基金Project supported by the National Natural Science Foundation of China(No.61672080)。
文摘Epigenetics’flexibility in terms of finer manipulation of genes renders unprecedented levels of refined and diverse evolutionary mechanisms possible.From the epigenetic perspective,the main limitations to improving the stability and accuracy of genetic algorithms are as follows:(1)the unchangeable nature of the external environment,which leads to excessive disorders in the changed phenotype after mutation and crossover;(2)the premature convergence due to the limited types of epigenetic operators.In this paper,a probabilistic environmental gradientdriven genetic algorithm(PEGA)considering epigenetic traits is proposed.To enhance the local convergence efficiency and acquire stable local search,a probabilistic environmental gradient(PEG)descent strategy together with a multi-dimensional heterogeneous exponential environmental vector tendentiously generates more offsprings along the gradient in the solution space.Moreover,to balance exploration and exploitation at different evolutionary stages,a variable nucleosome reorganization(VNR)operator is realized by dynamically adjusting the number of genes involved in mutation and crossover.Based on the above-mentioned operators,three epigenetic operators are further introduced to weaken the possible premature problem by enriching genetic diversity.The experimental results on the open Congress on Evolutionary Computation-2017(CEC’17)benchmark over 10-,30-,50-,and 100-dimensional tests indicate that the proposed method outperforms 10 state-of-the-art evolutionary and swarm algorithms in terms of accuracy and stability on comprehensive performance.The ablation analysis demonstrates that for accuracy and stability,the fusion strategy of PEG and VNR are effective on 96.55%of the test functions and can improve the indicators by up to four orders of magnitude.Furthermore,the performance of PEGA on the real-world spacecraft trajectory optimization problem is the best in terms of quality of the solution.
