ation Science and Technology,Lanzhou University,Lan

ommunication can be avoided.At the same time,it also removes the problems with P2P system multilayer grouping which can not update grouping in time and the grouping     

Science and Technology,Wuhan 4300

ss of composition,Many scholars have different studies.Through the vector space model,text clustering,genetic algorithms to try a new method summary of the text.Experiments by the vector space model expressed as a vector technology will form text,Text clustering algorithm to cluster a     

Effect of Wheat Middlings, Microbial Phytase, and Citric Acid on Phytate- Phosphorus, Calcium, and Protein Utilization of Broilers

A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%） （mg） （P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1） （P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.     

Preparation, Characterization, and Application of Antiharpin xoo Antibody

Polyclonal antiharpinxoo rabbit antibody has been prepared successfully using purified harpinxoo protein as an immunogen. The ELISA titer of the antiserum against harpinxoo was about 1：2 000. Western blot analysis showed that the antiserum could bind to the expression harpinxoo protein in particular, hrfl, encoding harpinxoo, is an expression in transgenic rice, detected by antiharpinxoo rabbit antibody. The rabbit antibody against harpinxoo can be used to study further about the biological function, harpinxoo localization, and hrfl gene expression in other plants.     

Beyond Biochar-Soil,Plant and Environment: Research Progress and Future Prospects

Since industrial revolution, the atmospheric CO2 concentration has kept a continuous increase by more than 2.2 ppm yr^-1, and approaches to almost 400 ppm at present （Jouzel 2012）. China has become the largest country of greenhouse gas emission （GHG）, and confronts with great challenge to mitigate GHG.     

Agrifood systems for competent, ordinary people. Presidential address: Joint Meetings of the Agricultural, Food and Human Values Society and the Association for the Study of Food and Society, Madison, Wisconsin, June 5–8, 1997

Focusing on the notion of competencies, the address explores important dimensions of human infrastructure for negotiating alternative agrifood systems. The analytical competencies emphasized are those of making connections and evaluating contradictions. Farm structure and food system connections with human health and consumer culture are chosen as examples. Examined in the context of social change strategies, relational competencies focus on new forms of food citizenship involving alternative organizational relationships between farmers, retailers, and customers. Ethical competencies are framed in relationship to the entire food system, to the valuing of non-market goods, and to linkages between ethics and emotions. Finally, aesthetic and spiritual competencies are considered as human capacities to connect agriculture and food with beauty and with sacramental living.     

Molecular Clone, Expression, and Prediction of Construction and Function to Key Genes of Interleukin Family of Porcine

This research was to clone, express, and analyze the structure and function of major molecules of porcine interleukin family. Genes of porcine interleukin family were cloned by RT-PCR from stimulated porcine PBMC by LPS and PHA, and then expressed in E. coli, and the structure and function of these molecules were predicted by ExPASY. The results showed that genes of IL-4, IL-6, and IL-18 were successfully cloned and expressed. Furthermore, the expression products of recombinant IL-4 and IL-6 both have multiple biological activities. By analyzing these genes with the NCBI/GenBank data, the homologies of the nucleotide acid sequence are 99.25, 99.21, and 100%, respectively, and have great species differences when compared with other animal species. The results of the prediction showed that all these molecules contain several phosphorylation, glycosylation, protein kinase, and signal transduction bonding sites in secondary structure, and all are compact globularity protein in space configuration. These characteristics of structure are the basis for their multiple biological functions. The genes, structure and function of key molecular of porcine interleukin family were successfully cloned, expressed, and analyzed in this paper.     

Effect of Phopshate Fertilizer and Manure on Crop Yield, Soil P Accumulation, and the Environmental Risk Assessment

Phosphorus （P） applied from fertilizer and manure is important in increasing crop yield and soil fertility; however, excessive uses of phosphate fertilizer and manure may also increase P loss from agricultural soils, posing environmental impact. A long term experiment was conducted on a calcareous soil （meadow cinnamon） in Hebei Province, China, from 2003 to 2006 to investigate the effects of phosphate fertilizer and manure on the yield of Chinese cabbage, soil P accumulation, P sorption saturation, soluble P in runoff water, and P leaching. P fertilizer （P2O5） application at a rate of 360 kg ha^-1 or manure of 150 t ha^-1 significantly increased Chinese cabbage yield as compared to the unfertilized control. However, no significant yield response was found with excessive phosphate or manure application. Soil Olsen-P, soluble P, bioavailable P, the degree of phosphorus sorption saturation in top soil layer （0-20 cm）, and soluble P in runoff water increased significantly with the increase of phosphate fertilizer and manure application rates, whereas the maximum phosphorus sorption capacity （Qm） decreased with the phosphate fertilizer and manure application rates. Soil Olsen-P and soluble P also increased significantly in the sub soil layer （20-40 cm） with the high P fertilizer and manure rates. It indicates that excessive P application over crop demand can lead to a high environmental risk owing to the enrichment of soil Olsen-P, soluble P, bioavailable P, and the degree of phosphorus sorption saturation in agricultural soils.     

Scientific Data： Preserving, Archiving and Sharing

Scientific and technical data is fundamental component for developing new knowledge, advancing technological progress, and creating wealth. The rapid rise of digital technologies in collecting, processing, and making available vast quantities of scientifi…     

China's alfalfa market and imports: Development,trends, and potential impacts of the U.S.–China trade dispute and retaliations

This study examines the development and trends of China's alfalfa market and imports, identifies key factors for the rapid increase in China's alfalfa imports, and discusses potential impacts of the U.S.–China trade dispute and retaliations on the alfalfa markets and trade in both nations. China's rapid transition toward larger-scale commercial dairy production, with enhanced feed and cost management as well as quality and safety control, and its limited resources for high-quality alfalfa production are key factors for the dramatic increase in its alfalfa imports, from 19 601 metric tons in 2008 to 1.38 million metric tons (mmt) in 2018. While the United States dominated China's alfalfa imports with an average share of 97.01% from 2007 to 2017, the share dropped to 83.76% in 2018 and 63.28% in January 2019 due to the trade dispute and retaliations started in 2018. China will likely remain a large importer of alfalfa because of both its growing demand and the comparative advantages of imported alfalfa in quality and price, but the imports from the United States will be highly affected by the ongoing trade dispute and negotiations. China is also expected to make more efforts to reduce its dependence on U.S. alfalfa through increased investment in domestic alfalfa production and identification of alternative sources of alfalfa and other hay imports.     

Accumulation Pattern of Gliadin Fractions α, β, γ, ω and Regulation of Nitrogen

Gliadin, the major storage protein in endosperm, affects grain quality in spring wheat by its content and composition. Eighteen cultivars differing in HMW-GS were used in the study to approach the accumulation pattern of gliadin fractions α, β, γ, ω and regulation of three kinds of nitrogen source. The results showed that the content of gliadin in grains increased gradually along with the process of grain-filling, but the accumulation intensity and final content differed evidently among cultivars with different HMW-GS composition. Of all the subunit types used here, cultivars with subunits 7＋9 and 2＋12 had smaller accumulation intensity and lower final content. During grain-filling, 4 gliadin fractions had the same increase trend, but differed in accumulation course. The dynamic trends of gliadin accumulation were similar in different nitrogen treatments whose effects on initial amount, accumulation intensity and final level of accumulation varied with cultivars. Of three nitrogen fertilizer types, the amide-form nitrogen source was better to the formation and accumulation of gliadin as well as its four fractions.     

Genetics, Development, and Application of Cytoplasmic Herbicide Resistance in Foxtail Millet

The effect of cytoplasmic herbicide resistant gene in millet plants was studied. The heterozygous populations and isogenic lines with homocaryotic alloplasmic genes were obtained by crossing and reciprocal crossing of cytoplasmic herbicide resistant plants with susceptive plants of foxtail millet. The characters of F1, F2, backcross and composite cross groups, and the growth and development of isogenic lines were compared. The cytoplasmic herbicide resistant gene slowed the development of seedling, delayed heading, and shortened the milking stage in the foxtail millet plant. Yield capacity and main agronomic characters were all affected by the cytoplasmic herbicide resistant gene in most of the backcross, composite cross, and F2 populations. However, there was stronger hybrid vigor in F1. The backcrosses, composite crosses, and F2 populations were widely separated and some of them had good characters similar to those of susceptive groups. The plant characters and development of foxtail millet were negatively affected by the cytoplasmic herbicide resistant gene. The authors proposed a method of using hybrid vigor to obtain high yield and avoid the negative effects of herbicide resistance cytoplasm in plant growth. The expected results could be obtained by selecting individuals in separate populations of fast developed seedlings, well-developed roots, and with capacities of early heading and fast milking. Guided by the principal mentioned above, many high yield lines and hybrid crosses of foxtail millet with herbicide resistant cytoplasm were obtained.