Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that dif...Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that differ in their proximate composition, amino acids, fatty acids, and minerals. Wild fish had a significantly lower crude lipid contents than cultured fish (P P ∑PUFAs) showed an obviously opposite trend. As compared with cultured fish, wild fish had significantly higher levels of n-3 PUFAs, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahxaenoic acid (DHA) (P P > 0.05), except for Na, Fe and Se. In conclusion, diet composition and external aqueous environment may determine the differences between wild and cultured topmouth culter.展开更多
Metasequoia glyptostroboides is an endangered relict plant native to China that has been widely introduced into many countries and areas around the world. However,its seeds germinate at a very low percentage. Conseque...Metasequoia glyptostroboides is an endangered relict plant native to China that has been widely introduced into many countries and areas around the world. However,its seeds germinate at a very low percentage. Consequently,population regeneration by seed is low under natural conditions, which probably contributes to the endangered status of this plant species. The present study aimed to describe the aging mechanism of M. glyptostroboides seeds. Our objective was to elucidate causes of the low germination rate in an effort to enhance potential for conservation of the species. We used germination tests,relative electrical conductivity and malondialdehyde content determination, ultrastructural observation of embryo cells, and analysis of superoxide dismutase, catalase,ascorbate peroxidase, and dehydroascorbate reductase activities during accelerated aging treatment. We found that M. glyptostroboides seeds have a low level of vigorand poor ability to maintain vigor, which is probably associated with the inefficiency of its enzymatic antioxidative system.展开更多
In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composi...In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composition of PM and fish meal were determined and compared.The results showed that the contents of moisture,crude protein,crude fat and ash in PM and fish meal were 3.25%and 8.92%,66.65%and 66.67%,13.52%and 8.23%,18.25%and 21.50%,respectively.The contents of essential amino acids(EAA)in PM and fish meal were 19.94%and 22.35%,respectively.For PM and fish meal,the first limiting amino acid was Met(methionine)+Cys(cysteine),and the second limiting amino acid was Lys(lysine);their essential amino acid indexes(EAAI)were 66.60 and 77.04,respectively;and their delicious amino acid(DAA)contents were 26.89%and 23.15%,respectively.In summary,the meat and bone meal of pigs died of non-communicable diseases has the characteristics of high protein and low ash contents,and has certain development and utilization potential as a recycled waste resource,especially in aquatic feed to replace fish meal.展开更多
Dove tree(Davidia involucrata),a tertiary vestige species,is well-adapted to cool conditions.Dormancy in D.involucrata seed lasts for an extremely long period of time,typically between 3 and 4 years,and this character...Dove tree(Davidia involucrata),a tertiary vestige species,is well-adapted to cool conditions.Dormancy in D.involucrata seed lasts for an extremely long period of time,typically between 3 and 4 years,and this characteristic makes the species an excellent model for studying the mechanisms of seed dormancy.The molecular mechanisms governing germination control in D.involucrata are still unknown.Seed stratification have been reported to enhance germination in recalcitrant seeds.We performed a widely targeted metabolome profiling to identify metabolites and associated pathways in D.involucrata seeds from six different moist sand stratification durations(0-30 months) using the ultra-high-performance liquid chromatography-Q Exactive Orbitrap-Mass spectrometry.There was an increasing germination rate with prolonged stratification durations(12-30 months).Furthermore,we detected 10,008 metabolites in the stratified seeds.We also detected 48 differentially accumulated metabolites(DAMs) between all stratification periods in the seeds,with 10 highly conserved metabolites.Most of the differentially accumulated metabolites between unstratified and stratified seeds were enriched in purine metabolism,pyrimidine metabolism,flavone and flavonol biosynthesis,phenylpropanoid biosynthesis,and arginine biosynthesis pathways.Key phytohormones,abscisic acid,indole-3 acetic acid,and sinapic acid were differentially accumulated in the seeds and are predicted to regulate dormancy in D.involucrata.We have provided extensive metabolic information useful for future works on dove tree germination study.展开更多
Two dominant strains of bacteria Lb18-01 and Lb18-02 were isolated and purified from scabies,liver and intestine of diseased Peodiscus sinensis.By artificial infection test,the two strains were verified as pathogenic ...Two dominant strains of bacteria Lb18-01 and Lb18-02 were isolated and purified from scabies,liver and intestine of diseased Peodiscus sinensis.By artificial infection test,the two strains were verified as pathogenic strains with similar characters to that of natural infectious cases.The strains Lb18-01 and Lb18-02 showed strong pathogenicity to healthy P.sinensis in the artificial infection experiment,so they were the pathogenic strain of the disease.According to the morphology,physicochemical characteristics,16 S rDNA sequence analysis and phylogenetic tree clustering,the pathogenic strains Lb18-01 and Lb18-02 were identified as Proteus vulgaris and Chryseobacterium meningosepticum which were tolerant to 20 drugs such as penicillin,tetracycline and ampicillin.Histopathological observation on diseased P.sinensis showed the pathological symptoms of sepsis such as hemorrhage and congestion of liver,spleen and intestine,and glomerular disintegration.展开更多
Temperature and humidity are two important factors that influence both indoor thermal comfort and air quality.Through varying compressor and supply fan speeds of a direct expansion(DX)air conditioning(A/C)unit,the air...Temperature and humidity are two important factors that influence both indoor thermal comfort and air quality.Through varying compressor and supply fan speeds of a direct expansion(DX)air conditioning(A/C)unit,the air temperature and humidity in the conditioned space can be regulated simultaneously.However,most existing controllers are designed to minimize the tracking errors between the system outputs with their corresponding settings as quickly as possible.The energy consumption,which is directly influenced by the compressor and supply fan speeds,is not considered in the relevant controller formulations,and thus the system may not operate with the highest possible energy efficiency.To effectively control temperature and humidity while minimizing the system energy consumption,a model predictive control(MPC)strategy was developed for a DX A/C system,and the development results are presented in this paper.A physically-based dynamic model for the DX A/C system with both sensible and latent heat transfers being considered was established and validated by experiments.To facilitate the design of MPC,the physical model was further linearized.The MPC scheme was then developed by formulating the objective function which sought to minimize the tracking errors of temperature and moisture content while saving energy consumption.Based on the results of command following and disturbance rejection tests,the proposed MPC scheme was capable of controlling temperature and humidity with adequate control accuracy and sensitivity.In comparison to linear-quadratic-Gaussian(LQG)controller,better control accuracy and lower energy consumption could be realized when using the proposed MPC strategy to simultaneously control temperature and humidity.展开更多
文摘Research was conducted on topmouth culter (Culter alburnus) grown in ponds and lakes as well as wild types in order to determine their chemical composition and nutritional value. There are three types of fish that differ in their proximate composition, amino acids, fatty acids, and minerals. Wild fish had a significantly lower crude lipid contents than cultured fish (P P ∑PUFAs) showed an obviously opposite trend. As compared with cultured fish, wild fish had significantly higher levels of n-3 PUFAs, arachidonic acid (AA), eicosapentaenoic acid (EPA) and docosahxaenoic acid (DHA) (P P > 0.05), except for Na, Fe and Se. In conclusion, diet composition and external aqueous environment may determine the differences between wild and cultured topmouth culter.
基金supported by the Research Project of Hubei Provincial Department of Education(Q20141902)。
文摘Metasequoia glyptostroboides is an endangered relict plant native to China that has been widely introduced into many countries and areas around the world. However,its seeds germinate at a very low percentage. Consequently,population regeneration by seed is low under natural conditions, which probably contributes to the endangered status of this plant species. The present study aimed to describe the aging mechanism of M. glyptostroboides seeds. Our objective was to elucidate causes of the low germination rate in an effort to enhance potential for conservation of the species. We used germination tests,relative electrical conductivity and malondialdehyde content determination, ultrastructural observation of embryo cells, and analysis of superoxide dismutase, catalase,ascorbate peroxidase, and dehydroascorbate reductase activities during accelerated aging treatment. We found that M. glyptostroboides seeds have a low level of vigorand poor ability to maintain vigor, which is probably associated with the inefficiency of its enzymatic antioxidative system.
基金Major Science and Technology Special Project in Hunan(2017NK1030)Earmarked Fund for China Agriculture Research System(CARS-45-48)。
文摘In order to explore the resource utilization of the harmless treatment product(pork meat and bone meal,abbreviated PM)of pigs died of non-communicable diseases,the general nutritional components and amino acid composition of PM and fish meal were determined and compared.The results showed that the contents of moisture,crude protein,crude fat and ash in PM and fish meal were 3.25%and 8.92%,66.65%and 66.67%,13.52%and 8.23%,18.25%and 21.50%,respectively.The contents of essential amino acids(EAA)in PM and fish meal were 19.94%and 22.35%,respectively.For PM and fish meal,the first limiting amino acid was Met(methionine)+Cys(cysteine),and the second limiting amino acid was Lys(lysine);their essential amino acid indexes(EAAI)were 66.60 and 77.04,respectively;and their delicious amino acid(DAA)contents were 26.89%and 23.15%,respectively.In summary,the meat and bone meal of pigs died of non-communicable diseases has the characteristics of high protein and low ash contents,and has certain development and utilization potential as a recycled waste resource,especially in aquatic feed to replace fish meal.
基金funded by the National Natural Sciences Foundation of China (31460203,31860073)Research Center for Germplasm Engineering of Characteristic Plant Resources in Enshi Prefecture (2019-2021)Hubei Key Laboratory of Biological Resources Protection and Utilization (PT012204)
文摘Dove tree(Davidia involucrata),a tertiary vestige species,is well-adapted to cool conditions.Dormancy in D.involucrata seed lasts for an extremely long period of time,typically between 3 and 4 years,and this characteristic makes the species an excellent model for studying the mechanisms of seed dormancy.The molecular mechanisms governing germination control in D.involucrata are still unknown.Seed stratification have been reported to enhance germination in recalcitrant seeds.We performed a widely targeted metabolome profiling to identify metabolites and associated pathways in D.involucrata seeds from six different moist sand stratification durations(0-30 months) using the ultra-high-performance liquid chromatography-Q Exactive Orbitrap-Mass spectrometry.There was an increasing germination rate with prolonged stratification durations(12-30 months).Furthermore,we detected 10,008 metabolites in the stratified seeds.We also detected 48 differentially accumulated metabolites(DAMs) between all stratification periods in the seeds,with 10 highly conserved metabolites.Most of the differentially accumulated metabolites between unstratified and stratified seeds were enriched in purine metabolism,pyrimidine metabolism,flavone and flavonol biosynthesis,phenylpropanoid biosynthesis,and arginine biosynthesis pathways.Key phytohormones,abscisic acid,indole-3 acetic acid,and sinapic acid were differentially accumulated in the seeds and are predicted to regulate dormancy in D.involucrata.We have provided extensive metabolic information useful for future works on dove tree germination study.
基金Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals(2018TP1027)Key R&D Projects of Hunan Province(2018NK2074).
文摘Two dominant strains of bacteria Lb18-01 and Lb18-02 were isolated and purified from scabies,liver and intestine of diseased Peodiscus sinensis.By artificial infection test,the two strains were verified as pathogenic strains with similar characters to that of natural infectious cases.The strains Lb18-01 and Lb18-02 showed strong pathogenicity to healthy P.sinensis in the artificial infection experiment,so they were the pathogenic strain of the disease.According to the morphology,physicochemical characteristics,16 S rDNA sequence analysis and phylogenetic tree clustering,the pathogenic strains Lb18-01 and Lb18-02 were identified as Proteus vulgaris and Chryseobacterium meningosepticum which were tolerant to 20 drugs such as penicillin,tetracycline and ampicillin.Histopathological observation on diseased P.sinensis showed the pathological symptoms of sepsis such as hemorrhage and congestion of liver,spleen and intestine,and glomerular disintegration.
基金supports for the Science and Technology Project of Zhejiang Province(No.LGG21F030009)the Natural Science Foundation of Zhejiang Province(No.LY20F030010)the Key R&D Projects in Zhejiang Province(No.2020C01164)are gratefully acknowledged.
文摘Temperature and humidity are two important factors that influence both indoor thermal comfort and air quality.Through varying compressor and supply fan speeds of a direct expansion(DX)air conditioning(A/C)unit,the air temperature and humidity in the conditioned space can be regulated simultaneously.However,most existing controllers are designed to minimize the tracking errors between the system outputs with their corresponding settings as quickly as possible.The energy consumption,which is directly influenced by the compressor and supply fan speeds,is not considered in the relevant controller formulations,and thus the system may not operate with the highest possible energy efficiency.To effectively control temperature and humidity while minimizing the system energy consumption,a model predictive control(MPC)strategy was developed for a DX A/C system,and the development results are presented in this paper.A physically-based dynamic model for the DX A/C system with both sensible and latent heat transfers being considered was established and validated by experiments.To facilitate the design of MPC,the physical model was further linearized.The MPC scheme was then developed by formulating the objective function which sought to minimize the tracking errors of temperature and moisture content while saving energy consumption.Based on the results of command following and disturbance rejection tests,the proposed MPC scheme was capable of controlling temperature and humidity with adequate control accuracy and sensitivity.In comparison to linear-quadratic-Gaussian(LQG)controller,better control accuracy and lower energy consumption could be realized when using the proposed MPC strategy to simultaneously control temperature and humidity.
