First-principles investigation of N-Ag co-doping effect on electronic properties in p-type ZnO

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.

Design of an agricultural economic statistical digitalized system

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.

The Inhibiting Effect of Bone Protein Hydrolysates on Lipid Oxidation in Pork Patties

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.

Experimental research on shear carrying capacity of H-steel concrete composite beam with small shear span ratio

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.

Study on the Effects of Cytokine Level in Ducklings with Selenium Poisoning

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.

Extending Shelf Life of Chilled Pork by Combination of Chitosan Coating With Spice Extracts

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.

Studies on Mucosal Immunity Induced by Transmissible Gastroenteritis Virus Nucleocapsid Protein Recombinant Lactobacillus casei in Mice and Sow

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.

Supplier pricing based on threshold cointegration in agri-supply chain

Aiming at the 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 test 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.

New Progress of Power Electronic On-Load Tap Changing Distributing Transformer

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.

Analysis of Simple Sequence Repeats in Genomes of Rhizobia

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.

Optimization of PCR System in EST-SSR Analysis of Phytophthora infestans

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.

Research on Virtual Simulation of Seeder

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.

Developing a genome-wide selection model for genetic improvement of residual feed intake and carcass merit in a beef cattle breeding program

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.

Effect of slow-release urea on soil nematode community structure in a Chinese soybean field

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.