The geometric structure, band structure and density of states of pure, Ag-doped, N-doped, and N-Ag codoped wurtzite ZnO have been investigated by the first-principles ultra-soft pseudopotential method based on the den...The geometric structure, band structure and density of states of pure, Ag-doped, N-doped, and N-Ag codoped wurtzite ZnO have been investigated by the first-principles ultra-soft pseudopotential method based on the density functional theory. The calculated results show that the carrier concentration is increased in the ZnO crystal codoped by N and Ag, and the codoped structure is stable and is more in favour of the formation of p-type ZnO.展开更多
The study investigated the university students' attitudes towards the coexistence of the standard discourse and the emergent discourses through a questionnaire. 223 sophomores in Xinjiang Normal University participat...The study investigated the university students' attitudes towards the coexistence of the standard discourse and the emergent discourses through a questionnaire. 223 sophomores in Xinjiang Normal University participated in the survey. The results show that these students tend to accept the emergent discourses in terms of their new vocabulary words, such as "yumi". Although the standard discourse dominates the students' life, the emergent discourses are accepted and used by these students. With regard to the view to purify the Chinese language, human concern and tolerance for the coexistence of various discourses are suggested.展开更多
ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Sou...ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Southern blot analysis indicated that ICE1 had been integrated into rice genome. Compared with the non-transgenic plants, the transgenic plants exhibited high resistance to hygromycin B and were consistent with the Mendelian inheritance of a single copy of the transgenic ICE1. Under the low temperature stress, the transgenic plants showed the lower mortality rate and the increased proline content. These results suggest that the Arabidopsis ICE1 is functional in rice and the over-expression of ICE1 improves the tolerance to cold stress in rice.展开更多
To improve the efficiency of the management of large farms, a digitalized system of economic statistics is designed based on the Internet platform of the digitalized agricultural integrated system of Friendship Farm, ...To improve the efficiency of the management of large farms, a digitalized system of economic statistics is designed based on the Internet platform of the digitalized agricultural integrated system of Friendship Farm, the largest farm in the world. The system can also realize data storage by using the access databank technology. A dynamic website system, based on ASP technology, is used to implement the on-line inquiry of the statistical index of the agricultural economy and the diagrams of the index every year. Furthermore, it can provide the value of comprehensive indicators of farms' economic profits for every year and a trend chart of the comprehensive appraisal of economic development, by using principal component analysis. An early-warning indicator boundary is decided based on the majority principle. The system can realize the farm's terminal data input with effective data-collecting channels and a normative gathering scope and system. This system breaks through the stand-alone database system in agricultural digitalized research to realize the database system in the Internet environment by integrating the existing technologies in China. The system lays a foundation for the further integrated research on the network platform of the digitalized agricultural integrated system in Friendship Farm.展开更多
Bone protein hydrolysates were prepared by limited alcalase hydrolysis (5 h). The hydrolysates were formulated (0-3%, w/w) into pork patties to determine the antioxidant efficacy. 0.02% BHA (butylated hydroxyanis...Bone protein hydrolysates were prepared by limited alcalase hydrolysis (5 h). The hydrolysates were formulated (0-3%, w/w) into pork patties to determine the antioxidant efficacy. 0.02% BHA (butylated hydroxyanisole) was used as a positive control. Lipid oxidation in patties during storage was analyzed by measuring the TBARS and protein carbonyl content. The results showed that bone protein hydrolysates possessed significant antioxidant activity, and antioxidant activity increased with the increasing hydrolysates concentration. Sensory evaluation indicated that bone protein hydrolysates improved the color and decreased lipid oxidation flavor of pork patties. The 2% bone hydrolysates possessed the highest antioxidant activity and better sensory quality, and its effect was closed to 0.02% BHA.展开更多
In order to investigate shear carrying capacity of H-steel concrete beam with small shear span ratio,shear test on 5 H-steel concrete composite beams with small span ratio (from 0.7 to 1.1) are reported,including test...In order to investigate shear carrying capacity of H-steel concrete beam with small shear span ratio,shear test on 5 H-steel concrete composite beams with small span ratio (from 0.7 to 1.1) are reported,including test design,test scheme,test method,failure characteristics and test results. Influences of shear span ratio,web of H steel and concrete on shear carrying capacity of this kind of beam are investigated. The main components comprising shear bearing capacity are analyzed. The results show that with the shear span ratio increasing,the contribution of web of H steel and concrete on shear carrying capacity decrease. Based on test data,the calculation formula of shear carrying capacity for this beam is established by curve fitting.展开更多
One-day-old healthy ducklings (n = 100) were randomly allocated into two groups (n = 50, respectively) to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group (...One-day-old healthy ducklings (n = 100) were randomly allocated into two groups (n = 50, respectively) to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group (Group Ⅰ) were fed with full rations containing 0.3 mg kg^-1 selenium, and the ducklings in selenium poisoning group (Group Ⅱ ) were fed with seleniumexcessive rations containing 8.0 mg kg^-1 selenium. One mL blood was collected by cardiac puncture at d 15, 30, 60, and 90 (n = 10, respectively), serum was separated by centrifugation. Contents of cytokines were determined by the radioimmunity method (RIA). The results showed that the contents of IL-113, IL-213 in Group Ⅱ were higher than that in control group at d 15 (P〉0.05), but were significantly lower at d 30, 60, and 90 (P〈0.01); the contents of IL-8β in Group II were significantly lower than that in control group (P〈0.01); the contents of erythropoietin (EPO) and IGF-2 in Group II were significantly lower in different degree than that in control group at d 60 and 90 (P〈0.01); the contents of granulocyte- macrophage colony stimulating factor (GM-CSF) in the two groups were lower in different degree and significantly lower at d 60 and 90 (P〈0.01). It can be concluded that the excessive selenium could result in a decrease in immunity and a series of clinical pathology changes, such as anemia, tissue hemorrhage, and necrosis.展开更多
During the process of enterprises' strategy evaluation and selection, there are many evaluating indicators, and among them there are some potential correlations and conflicts. Thus it poses the problems to the decisi...During the process of enterprises' strategy evaluation and selection, there are many evaluating indicators, and among them there are some potential correlations and conflicts. Thus it poses the problems to the decision-makers how to conduct correct evaluation on a business and how to make strategy adjustment and selection according to the evaluation. Based on the qualitative and quantitative method, the paper introduces the Projection Pursuit Classification (PPC) model based on the Real-coded Accelerating Genetic Algorithm (RAGA) into the process of enterprises' strategy evaluation and selection. The characteristic of PPC model is that it ultimately overcomes the influence of the proportion of subjectivity and avoids precocious convergence, thus providing a new objective method for strategy evaluation and selection by pursuing the most objective strategy evaluation to make the relatively sensible strategy portfolio and action.展开更多
The effects of spices(cinnamon,rosemary,clove)extracts and chitosan on microbiological growth,drip loss,color,and lipid oxidation of fresh chilled meat stored for 28 days at 4℃were investigated.There were four trea...The effects of spices(cinnamon,rosemary,clove)extracts and chitosan on microbiological growth,drip loss,color,and lipid oxidation of fresh chilled meat stored for 28 days at 4℃were investigated.There were four treatments:control,coated with spices(cinnamon 1.5 g·L^-1+rosemary 1.5 g·L^-1+clove 1.0 g·L^-1),coated with 0.5%chitosan,coated with spices and chitosan.Chitosan coating resulted in significant inhibition of microbial growth(P〈0.05),while the lowest microbial counts were obtained in the samples containing both chitosan and spices,indicating a possible synergistic effect.Chitosan and its combinations with spices also showed the most intense antioxidative effect when compared to the controls(P〈0.05).Meanwhile,chitosan coating could decrease water loss and keep better color of chilled meat.The combined spice extracts and chitosan coating could effectively extend the shelf life of chilled meat.展开更多
Mucosal immunity plays an important role in protecting pigs against transmissible gastroenteritis virus (TGEV) infection. To elicit mucosal immune response against TGEV, we developed a surface antigen display system...Mucosal immunity plays an important role in protecting pigs against transmissible gastroenteritis virus (TGEV) infection. To elicit mucosal immune response against TGEV, we developed a surface antigen display system using the poly-γ- glutamate synthetase A (pgsA) protein of Bacillus subtilis as an anchoring matrix to express recombinant fusion proteins of pgsA and nucleocapsid protein of TGEV in Lactobacillus casei. Surface location of fusion protein was verified by ELISA and indirect immunofluorescence test. Oral and intranasal inoculations of pregnant sow and mice with recombinant L. casei resulted in high levels of serum immunoglobulin G (IgG) and secretory immunoglobulin A (slgA) against recombinant N protein as demonstrated by ELISA. More importantly, the level of specific slgA in colostrum significantly increased compared with that of IgG. The serum IgG levels of the piglets increased after suckling colostrum produced by sows was previously inoculated with recombinant L. casei. These results indicate that immunization with recombinant L. casei expressing TGEV N protein on its surface elicited high levels of specific slgA and circulating IgG against TGEV N protein.展开更多
Aiming atthe pricing of primary agricultural products for the large-scale suppliers and the wholesalers in agri-supply chain management, an approach for the large-scale supplier pricing is presented based on the thres...Aiming atthe pricing of primary agricultural products for the large-scale suppliers and the wholesalers in agri-supply chain management, an approach for the large-scale supplier pricing is presented based on the threshold cointegration method of wholesale prices online including the GBand-TAR modified Band-TAR model. Our empirical work shows that it is more appropriate for a large-scale supplier pricing with his wholesalers based on the threshold cointegration method than the conventional linear cointegration method in spatially separate markets in an agri-supply chain of soybean in China in short time. Firstly, the three pairs of prices in spatially separate markets are of long-run equilibrium and threshold cointegration. The forecast wst shows that the threshold cointegration approach is superior to the conventional linear cointegration approach in short time. Secondly, there are two thresholds of GBand-TAR in which the threshold parameters represent relative transaction costs. Larger thresholds or wider neutral band corresponds to the greater distance between markets. Thirdly, the estimation of M-TAR shows that the large-scale supplier is more sensitive to increase of wholesaler prices than decrease of wholesaler prices. The supplier can price on the forecast of market price by the threshold ECM including the GBand-TAR if the equilibrium error of threshold lag is not in the interval of thresholds in which there is not profitable trading opportunities for the supplier.展开更多
At present, the widely applied mechanical on-load tap-changer is not suitable for the 10 kV power distribution network. Along with the development of power electronic technology, there has the report on on-load tap ch...At present, the widely applied mechanical on-load tap-changer is not suitable for the 10 kV power distribution network. Along with the development of power electronic technology, there has the report on on-load tap changing (OLTC) distributing transformer based on the power electronic technology. In this paper, the analysis on the characteristic of several kinds of non-contacts OLTC distributing transformer was carried on. The result indicates that OLTC distributing transformer based on the solid state relay has the broad applied prospect in the 10 kV medium distribution network.展开更多
Simple sequence repeats (SSRs) or microsatellites, as genetic markers, are ubiquitous in genomes of various organisms. The analysis of SSR in rhizobia genome provides useful information for a variety of applications...Simple sequence repeats (SSRs) or microsatellites, as genetic markers, are ubiquitous in genomes of various organisms. The analysis of SSR in rhizobia genome provides useful information for a variety of applications in population genetics of rhizobia. We analyzed the occurrences, relative abundance, and relative density of SSRs, the most common in Bradyrhizobium japonicum, Mesorhizobium loti, and Sinorhizobium meliloti genomes se- quenced in the microorganisms tandem repeats database, and SSRs in the three species genomes were compared with each other. The result showed that there were 1 410, 859, and 638 SSRs in B. japonicum, M. loti, and S. meliloti genomes, respectively. In the genomes of B. japonicum, M. loti, and S. meliloti, tetranucleotide, pentanucleotide, and hexanucleotide repeats were more abundant and indicated higher mutation rates in these species. The least abundance was mononucleotide repeat. The SSRs type and distribution were similar among these species.展开更多
Late blight caused by the oomycete Phytophthora infestans Montagne de Bary is a devastating disease on potato production. A total of six parameters affecting the PCR system in P. infestans were investigated based on t...Late blight caused by the oomycete Phytophthora infestans Montagne de Bary is a devastating disease on potato production. A total of six parameters affecting the PCR system in P. infestans were investigated based on the template DNA of the isolate HH06-23 and EST-SSR primer pair Pi08N. The results showed that the optimal annealing temperature was 63 ℃, and the optimum PCR system of EST-SSR was 25 ng template DNA, 0.5 mmol·L^-1 dNTPs, 2 μL 10×Buffer (Mg^2+ free), 1.75 mmol·L^-1 MgCl2, 15 pmol primer, and 1.2 U Taq DNA polymerase in total 20 μL reaction system. The PCR program was initial denaturation at 94℃ for 2 rain, followed by 35 cycles of 94℃ for 30 s, 63℃ for 30 s, and 72℃ for 30 s, then a final extension step was 72℃ for 7 min, and held at 4℃. In addition, using the optimal PCR system, a total of 20 isolates of P. infestans were used for testing the stability and polymorphism of the PCR amplification. The clarity and abundant polymorphism indicated that this system was stable and suitable for researching the genetic diversity ofP. infestans population.展开更多
In this study, the modeling and simulating of seeder were researched, and the method of virtual designing of seeder using computer was implemented. Based on these, general method of seeder virtual simulation was imple...In this study, the modeling and simulating of seeder were researched, and the method of virtual designing of seeder using computer was implemented. Based on these, general method of seeder virtual simulation was implemented using eon studio. The virtual designing, operation showing of farm machinery can be operated on website.展开更多
The author will show one an effective learning approach --- preview, which will benefit both students and teachers. "Compensation and teaching efficiency", "preview as a means to encourage students" and "developm...The author will show one an effective learning approach --- preview, which will benefit both students and teachers. "Compensation and teaching efficiency", "preview as a means to encourage students" and "development of self-study ability" are the three advantages of preview. There are four techniques of preview, which are "direct preview", "focal preview", "preview combined with exercises" and "preview intended to foster comprehension and aid consolidation". One will find out how to preview and what kind of benefits one will get from this paper.展开更多
Residual feed intake (RFI) and carcass merit (CM) are both complex traits emerging as critical targets for beef genetic improvement.RFI and CM traits are difficult and expensive to measure and genetic improvement for ...Residual feed intake (RFI) and carcass merit (CM) are both complex traits emerging as critical targets for beef genetic improvement.RFI and CM traits are difficult and expensive to measure and genetic improvement for these traits through traditional selection methods is not very effective.Therefore,genome-wide selection using DNA markers may be a potential alternative for genetic improvement of these traits.In this study,the efficiency of a genome-wide selection model for genetic improvement of RFI and CM was assessed.The Illumina Bovine50K bead chip was used to genotype 922 beef cattle from the Kinsella Beef Research Ranch of the University of Alberta.A Bayes model and multiple marker regression using a stepwise method were used to conduct the association test.The number of significant SNP markers for carcass weight (CWT),carcass back fat (BF),carcass rib eye area (REA),carcass grade fat (GDF),lean meat yield (LMY),and residual feed intake (RFI) were 75,54,67,57,44 and 50,respectively.Bi-variate analysis of marker scores and phenotypes for all traits were made using DMU Software.The genetic parameter for each trait was estimated.The genetic correlations of marker score and phenotype for CWT,BF,REA,GDF,LMY and RFI were 0.75,0.69,0.87,0.77,0.78,and 0.85,respectively.The average prediction accuracies of phenotypic EBV for the six traits were increased by 0.05,0.16,0.24,0.23,0.17 and 0.19,respectively.The results of this study indicated that the two-trait marker-assisted evaluation model used was a suitable alternative of genetic evaluation for these traits in beef cattle.展开更多
The effect of slow-release urea on soil nematode community structure was investigated in a soybean field in northeast China.Three treatments,no urea(CK),conventional urea(U)and slow-release urea(SRU),were arranged in ...The effect of slow-release urea on soil nematode community structure was investigated in a soybean field in northeast China.Three treatments,no urea(CK),conventional urea(U)and slow-release urea(SRU),were arranged in a completely random design.The results show that the abundance of total nematodes was significantly higher in SRU than in CK and U.Significant differences in the abundance of bacterivores with colonizer-persister(cp)values 2–3,fungivores with cp 2 and herbivores with cp 3 were found among different treatments.Forty-one genera were identified,of which Acrobeloides,Aphelenchus and Heterodera were dominant.Soil nematode guilds and genera exhibited different responses to slow-release urea.The most trophic groups and genera had greater abundances in SRU than in CK and U.Slow-release urea had a positive effect on soil nematode community structure.展开更多
文摘The geometric structure, band structure and density of states of pure, Ag-doped, N-doped, and N-Ag codoped wurtzite ZnO have been investigated by the first-principles ultra-soft pseudopotential method based on the density functional theory. The calculated results show that the carrier concentration is increased in the ZnO crystal codoped by N and Ag, and the codoped structure is stable and is more in favour of the formation of p-type ZnO.
文摘The study investigated the university students' attitudes towards the coexistence of the standard discourse and the emergent discourses through a questionnaire. 223 sophomores in Xinjiang Normal University participated in the survey. The results show that these students tend to accept the emergent discourses in terms of their new vocabulary words, such as "yumi". Although the standard discourse dominates the students' life, the emergent discourses are accepted and used by these students. With regard to the view to purify the Chinese language, human concern and tolerance for the coexistence of various discourses are suggested.
基金supported by a project grant from the Education Department of Heilongjiang Province, China (Grant No. 11511248).
文摘ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Southern blot analysis indicated that ICE1 had been integrated into rice genome. Compared with the non-transgenic plants, the transgenic plants exhibited high resistance to hygromycin B and were consistent with the Mendelian inheritance of a single copy of the transgenic ICE1. Under the low temperature stress, the transgenic plants showed the lower mortality rate and the increased proline content. These results suggest that the Arabidopsis ICE1 is functional in rice and the over-expression of ICE1 improves the tolerance to cold stress in rice.
基金The Key Technologies R& D Program of Heilongjiang Province (No.GB06B601)
文摘To improve the efficiency of the management of large farms, a digitalized system of economic statistics is designed based on the Internet platform of the digitalized agricultural integrated system of Friendship Farm, the largest farm in the world. The system can also realize data storage by using the access databank technology. A dynamic website system, based on ASP technology, is used to implement the on-line inquiry of the statistical index of the agricultural economy and the diagrams of the index every year. Furthermore, it can provide the value of comprehensive indicators of farms' economic profits for every year and a trend chart of the comprehensive appraisal of economic development, by using principal component analysis. An early-warning indicator boundary is decided based on the majority principle. The system can realize the farm's terminal data input with effective data-collecting channels and a normative gathering scope and system. This system breaks through the stand-alone database system in agricultural digitalized research to realize the database system in the Internet environment by integrating the existing technologies in China. The system lays a foundation for the further integrated research on the network platform of the digitalized agricultural integrated system in Friendship Farm.
基金Supported by Foundation of Science and Technology of 11th Five-Year Plan of Heilongjiang (GB06B403)
文摘Bone protein hydrolysates were prepared by limited alcalase hydrolysis (5 h). The hydrolysates were formulated (0-3%, w/w) into pork patties to determine the antioxidant efficacy. 0.02% BHA (butylated hydroxyanisole) was used as a positive control. Lipid oxidation in patties during storage was analyzed by measuring the TBARS and protein carbonyl content. The results showed that bone protein hydrolysates possessed significant antioxidant activity, and antioxidant activity increased with the increasing hydrolysates concentration. Sensory evaluation indicated that bone protein hydrolysates improved the color and decreased lipid oxidation flavor of pork patties. The 2% bone hydrolysates possessed the highest antioxidant activity and better sensory quality, and its effect was closed to 0.02% BHA.
基金Sponsored by the National Key Technologies R&D Program of China during the 11th Five-Year Plan Period (Grant No.2006BAJ03A10)"New Century Excellent Talents in University"Scheme (Grant No.290)+2 种基金the National Natural Science Foundation of China(Grant No.50178026)the Natural Science Foundation of Heilongjiang Province-General Project (Grant No.E200806)the Foundation of Harbin Program (Grant No.2005AFXXJ017)
文摘In order to investigate shear carrying capacity of H-steel concrete beam with small shear span ratio,shear test on 5 H-steel concrete composite beams with small span ratio (from 0.7 to 1.1) are reported,including test design,test scheme,test method,failure characteristics and test results. Influences of shear span ratio,web of H steel and concrete on shear carrying capacity of this kind of beam are investigated. The main components comprising shear bearing capacity are analyzed. The results show that with the shear span ratio increasing,the contribution of web of H steel and concrete on shear carrying capacity decrease. Based on test data,the calculation formula of shear carrying capacity for this beam is established by curve fitting.
文摘One-day-old healthy ducklings (n = 100) were randomly allocated into two groups (n = 50, respectively) to investigate the effect of cytokines on ducklings with selenium poisoning. The ducklings in control group (Group Ⅰ) were fed with full rations containing 0.3 mg kg^-1 selenium, and the ducklings in selenium poisoning group (Group Ⅱ ) were fed with seleniumexcessive rations containing 8.0 mg kg^-1 selenium. One mL blood was collected by cardiac puncture at d 15, 30, 60, and 90 (n = 10, respectively), serum was separated by centrifugation. Contents of cytokines were determined by the radioimmunity method (RIA). The results showed that the contents of IL-113, IL-213 in Group Ⅱ were higher than that in control group at d 15 (P〉0.05), but were significantly lower at d 30, 60, and 90 (P〈0.01); the contents of IL-8β in Group II were significantly lower than that in control group (P〈0.01); the contents of erythropoietin (EPO) and IGF-2 in Group II were significantly lower in different degree than that in control group at d 60 and 90 (P〈0.01); the contents of granulocyte- macrophage colony stimulating factor (GM-CSF) in the two groups were lower in different degree and significantly lower at d 60 and 90 (P〈0.01). It can be concluded that the excessive selenium could result in a decrease in immunity and a series of clinical pathology changes, such as anemia, tissue hemorrhage, and necrosis.
文摘During the process of enterprises' strategy evaluation and selection, there are many evaluating indicators, and among them there are some potential correlations and conflicts. Thus it poses the problems to the decision-makers how to conduct correct evaluation on a business and how to make strategy adjustment and selection according to the evaluation. Based on the qualitative and quantitative method, the paper introduces the Projection Pursuit Classification (PPC) model based on the Real-coded Accelerating Genetic Algorithm (RAGA) into the process of enterprises' strategy evaluation and selection. The characteristic of PPC model is that it ultimately overcomes the influence of the proportion of subjectivity and avoids precocious convergence, thus providing a new objective method for strategy evaluation and selection by pursuing the most objective strategy evaluation to make the relatively sensible strategy portfolio and action.
基金Supported by the Student Abroad Foundation of Harbin(RC2006LX020003)
文摘The effects of spices(cinnamon,rosemary,clove)extracts and chitosan on microbiological growth,drip loss,color,and lipid oxidation of fresh chilled meat stored for 28 days at 4℃were investigated.There were four treatments:control,coated with spices(cinnamon 1.5 g·L^-1+rosemary 1.5 g·L^-1+clove 1.0 g·L^-1),coated with 0.5%chitosan,coated with spices and chitosan.Chitosan coating resulted in significant inhibition of microbial growth(P〈0.05),while the lowest microbial counts were obtained in the samples containing both chitosan and spices,indicating a possible synergistic effect.Chitosan and its combinations with spices also showed the most intense antioxidative effect when compared to the controls(P〈0.05).Meanwhile,chitosan coating could decrease water loss and keep better color of chilled meat.The combined spice extracts and chitosan coating could effectively extend the shelf life of chilled meat.
基金supported by the fund of the Key Science and Technology Research during the 10th Five-Year-Plan period in Heilongjiang Province, China(GB05B501-2).
文摘Mucosal immunity plays an important role in protecting pigs against transmissible gastroenteritis virus (TGEV) infection. To elicit mucosal immune response against TGEV, we developed a surface antigen display system using the poly-γ- glutamate synthetase A (pgsA) protein of Bacillus subtilis as an anchoring matrix to express recombinant fusion proteins of pgsA and nucleocapsid protein of TGEV in Lactobacillus casei. Surface location of fusion protein was verified by ELISA and indirect immunofluorescence test. Oral and intranasal inoculations of pregnant sow and mice with recombinant L. casei resulted in high levels of serum immunoglobulin G (IgG) and secretory immunoglobulin A (slgA) against recombinant N protein as demonstrated by ELISA. More importantly, the level of specific slgA in colostrum significantly increased compared with that of IgG. The serum IgG levels of the piglets increased after suckling colostrum produced by sows was previously inoculated with recombinant L. casei. These results indicate that immunization with recombinant L. casei expressing TGEV N protein on its surface elicited high levels of specific slgA and circulating IgG against TGEV N protein.
基金the Social Science Fund Program of Heilongjiang Province in China(Grant No.03B028)
文摘Aiming atthe pricing of primary agricultural products for the large-scale suppliers and the wholesalers in agri-supply chain management, an approach for the large-scale supplier pricing is presented based on the threshold cointegration method of wholesale prices online including the GBand-TAR modified Band-TAR model. Our empirical work shows that it is more appropriate for a large-scale supplier pricing with his wholesalers based on the threshold cointegration method than the conventional linear cointegration method in spatially separate markets in an agri-supply chain of soybean in China in short time. Firstly, the three pairs of prices in spatially separate markets are of long-run equilibrium and threshold cointegration. The forecast wst shows that the threshold cointegration approach is superior to the conventional linear cointegration approach in short time. Secondly, there are two thresholds of GBand-TAR in which the threshold parameters represent relative transaction costs. Larger thresholds or wider neutral band corresponds to the greater distance between markets. Thirdly, the estimation of M-TAR shows that the large-scale supplier is more sensitive to increase of wholesaler prices than decrease of wholesaler prices. The supplier can price on the forecast of market price by the threshold ECM including the GBand-TAR if the equilibrium error of threshold lag is not in the interval of thresholds in which there is not profitable trading opportunities for the supplier.
文摘At present, the widely applied mechanical on-load tap-changer is not suitable for the 10 kV power distribution network. Along with the development of power electronic technology, there has the report on on-load tap changing (OLTC) distributing transformer based on the power electronic technology. In this paper, the analysis on the characteristic of several kinds of non-contacts OLTC distributing transformer was carried on. The result indicates that OLTC distributing transformer based on the solid state relay has the broad applied prospect in the 10 kV medium distribution network.
基金the program of Key Sci-ence and Technology Research from the Department of Science and Technology of General Bureau of Land Reclamation of Heilongjiang Province, China (HNKXIV-02-03-03)
文摘Simple sequence repeats (SSRs) or microsatellites, as genetic markers, are ubiquitous in genomes of various organisms. The analysis of SSR in rhizobia genome provides useful information for a variety of applications in population genetics of rhizobia. We analyzed the occurrences, relative abundance, and relative density of SSRs, the most common in Bradyrhizobium japonicum, Mesorhizobium loti, and Sinorhizobium meliloti genomes se- quenced in the microorganisms tandem repeats database, and SSRs in the three species genomes were compared with each other. The result showed that there were 1 410, 859, and 638 SSRs in B. japonicum, M. loti, and S. meliloti genomes, respectively. In the genomes of B. japonicum, M. loti, and S. meliloti, tetranucleotide, pentanucleotide, and hexanucleotide repeats were more abundant and indicated higher mutation rates in these species. The least abundance was mononucleotide repeat. The SSRs type and distribution were similar among these species.
基金Supported by Natural Science Foundation of Heilongjiang Province of China (C200622)
文摘Late blight caused by the oomycete Phytophthora infestans Montagne de Bary is a devastating disease on potato production. A total of six parameters affecting the PCR system in P. infestans were investigated based on the template DNA of the isolate HH06-23 and EST-SSR primer pair Pi08N. The results showed that the optimal annealing temperature was 63 ℃, and the optimum PCR system of EST-SSR was 25 ng template DNA, 0.5 mmol·L^-1 dNTPs, 2 μL 10×Buffer (Mg^2+ free), 1.75 mmol·L^-1 MgCl2, 15 pmol primer, and 1.2 U Taq DNA polymerase in total 20 μL reaction system. The PCR program was initial denaturation at 94℃ for 2 rain, followed by 35 cycles of 94℃ for 30 s, 63℃ for 30 s, and 72℃ for 30 s, then a final extension step was 72℃ for 7 min, and held at 4℃. In addition, using the optimal PCR system, a total of 20 isolates of P. infestans were used for testing the stability and polymorphism of the PCR amplification. The clarity and abundant polymorphism indicated that this system was stable and suitable for researching the genetic diversity ofP. infestans population.
基金Supported by Heilongjiang New Century High Education Teaching Reform Project (HeiJiaoGaoHan[2008]No.8)
文摘In this study, the modeling and simulating of seeder were researched, and the method of virtual designing of seeder using computer was implemented. Based on these, general method of seeder virtual simulation was implemented using eon studio. The virtual designing, operation showing of farm machinery can be operated on website.
文摘The author will show one an effective learning approach --- preview, which will benefit both students and teachers. "Compensation and teaching efficiency", "preview as a means to encourage students" and "development of self-study ability" are the three advantages of preview. There are four techniques of preview, which are "direct preview", "focal preview", "preview combined with exercises" and "preview intended to foster comprehension and aid consolidation". One will find out how to preview and what kind of benefits one will get from this paper.
基金supported by the Alberta Livestock and Meat Agency(ALMA)(G550000101)ALMA/Alberta Agricultural Research Institute(AARI)(G550000127)National Natural Science Foundation of China(30771534) who are greatly acknowledged
文摘Residual feed intake (RFI) and carcass merit (CM) are both complex traits emerging as critical targets for beef genetic improvement.RFI and CM traits are difficult and expensive to measure and genetic improvement for these traits through traditional selection methods is not very effective.Therefore,genome-wide selection using DNA markers may be a potential alternative for genetic improvement of these traits.In this study,the efficiency of a genome-wide selection model for genetic improvement of RFI and CM was assessed.The Illumina Bovine50K bead chip was used to genotype 922 beef cattle from the Kinsella Beef Research Ranch of the University of Alberta.A Bayes model and multiple marker regression using a stepwise method were used to conduct the association test.The number of significant SNP markers for carcass weight (CWT),carcass back fat (BF),carcass rib eye area (REA),carcass grade fat (GDF),lean meat yield (LMY),and residual feed intake (RFI) were 75,54,67,57,44 and 50,respectively.Bi-variate analysis of marker scores and phenotypes for all traits were made using DMU Software.The genetic parameter for each trait was estimated.The genetic correlations of marker score and phenotype for CWT,BF,REA,GDF,LMY and RFI were 0.75,0.69,0.87,0.77,0.78,and 0.85,respectively.The average prediction accuracies of phenotypic EBV for the six traits were increased by 0.05,0.16,0.24,0.23,0.17 and 0.19,respectively.The results of this study indicated that the two-trait marker-assisted evaluation model used was a suitable alternative of genetic evaluation for these traits in beef cattle.
基金This research was supported by the Key Project of the Heilongjiang Provincial Bureau of Science and Technology(No.GA06C101-01)。
文摘The effect of slow-release urea on soil nematode community structure was investigated in a soybean field in northeast China.Three treatments,no urea(CK),conventional urea(U)and slow-release urea(SRU),were arranged in a completely random design.The results show that the abundance of total nematodes was significantly higher in SRU than in CK and U.Significant differences in the abundance of bacterivores with colonizer-persister(cp)values 2–3,fungivores with cp 2 and herbivores with cp 3 were found among different treatments.Forty-one genera were identified,of which Acrobeloides,Aphelenchus and Heterodera were dominant.Soil nematode guilds and genera exhibited different responses to slow-release urea.The most trophic groups and genera had greater abundances in SRU than in CK and U.Slow-release urea had a positive effect on soil nematode community structure.