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Lu S.,China Agricultural University | Lu S.,Tianjin Agricultural College | Yan Z.,China Agricultural University | Chen Q.,China Agricultural University | Zhang F.,China Agricultural University
Journal of Plant Nutrition | Year: 2012

Conventional practices of nitrogen (N) and phosphorus (P) application were evaluated based on nutrient balance calculation and soil N and P level from 916 surveyed orchards in North China, in order to assess the potential environmental risks. The results showed that excessive N and P application was common, with the average input rates of 588.4 kg N ha-1, and 156.7 kg P ha-1, respectively, which were 2.5-3.0 folds higher than the fruit N and P demand. High proportions of surplus N and P were found in grape, apple, pear and peach orchards in the plain regions with high economic returns. Nitrogen surplus reduced soil carbon (C)/N ratio in the plain, plateau and mountain regions. High soil Olsen-P level in the 40% of surveyed orchards, predominantly distributed in grape and peach orchards, was over the environmental threshold. Controlling N and P fertilization is the key to maintain sustainable fruit production in North China. © 2012 Copyright Taylor and Francis Group, LLC.

Cheng Z.,Texas A&M University | Cheng Z.,Tianjin Agricultural College | Buentello A.,Texas A&M University | Gatlin D.M.,Texas A&M University
Aquaculture | Year: 2011

Both arginine and glutamine play important roles in tissue repair, cell replication and collagen synthesis which impact animal growth and survival. Thus, a 7-week feeding trial was conducted to determine the effects of dietary arginine and glutamine on growth performance, innate immune responses and intestinal structure of juvenile red drum, Sciaenops ocellatus (6.9 ± 0.04. g, initial average weight). Protein in all experimental diets was derived from menhaden fishmeal and dehulled, solvent-extracted soybean meal to provide isonitrogenous (44% crude protein) and isolipidic (10%) diets. The basal diet contained 0.14% glutamine and 1.72% arginine on a dry-matter basis, which exceeds the established dietary requirement of red drum. Experimental diets were prepared by supplementing the basal diet with either arginine at 1% of dry weight, glutamine at 1%, glutamine at 2%, or both arginine and glutamine at 1%, with adjustments in glycine to maintain equal nitrogen among all diets.Feed efficiency was significantly (P< 0.05) improved by supplementation of glutamine at 2% and the combination of both arginine and glutamine at 1% of diet. Neutrophil oxidative radical production in fish fed the glutamine and/or arginine-supplemented diets was significantly (P= 0.03) higher compared with that of fish fed the basal diet, with a synergistic effect observed in fish fed the combined arginine-glutamine diet. Significantly (P< 0.05) higher serum lysozyme activity also was observed in fish fed the diet supplemented with 1% of both arginine and glutamine. Extracellular superoxide anion production by red drum macrophages was significantly (P< 0.05) higher for fish fed diets with glutamine at either 1 or 2% and the 1% arginine-glutamine combination compared to fish fed the basal diet. Similarly, macrophages from fish fed the diet with glutamine at 2% and the arginine-glutamine combination at 1% produced significantly higher amounts of intracellular superoxide anion.Morphometric analyses - i.e., measurements of enterocyte, microvillus and fold heights - demonstrated positive effects of both dietary glutamine and arginine in different portions (proximal, mid and distal) of the gastrointestinal tract of red drum. In general, fish fed the diet supplemented with 2% glutamine had the greatest increases in magnitude of the chosen structures, although those fed the diet with arginine at 1% also yielded improved scores for some enteric portions. Therefore, results from the present study establish the importance of both dietary arginine and glutamine supplementation in improving feed efficiency, as well as eliciting positive changes to several components of the innate immune system and intestinal functionality of red drum. © 2011 Elsevier B.V.

Gai Y.,CAS Qingdao Institute of Oceanology | Gai Y.,University of Chinese Academy of Sciences | Wang L.,CAS Qingdao Institute of Oceanology | Song L.,CAS Qingdao Institute of Oceanology | And 3 more authors.
Fish and Shellfish Immunology | Year: 2010

Insulin growth factor binding proteins (IGFBPs), characterized by the conserved insulin binding (IB) domains, are important components of endocrine system and play key roles in metabolism and growth. In the present study, the full-length cDNA of a single IB domain protein (designated EsSIBD) was identified from Chinese mitten crab Eriocheir sinensis based on expressed sequence tag (EST) sequence. The 1187 bp EsSIBD cDNA contained a 321 bp open reading frame (ORF) encoding a putative protein of 106 amino acids, a 5′-untranslated region (UTR) of 189 bp, and a 3′-UTR of 677 bp. Multiple sequence alignment presented ten conserved cysteine residues critical for the fundamental structure and function of IB domain. BLAST analysis revealed that EsSIBD shared high similarity with previously known IB domains of IGFBPs with the identities ranging from 40% to 46%. The sequence similarity and domain conservation indicated that EsSIBD was a potential member of the IGFBP family. Phylogenic analysis presented that EsSIBD was closer to IGFBP7 than to the other IB domain containing proteins, suggesting its functional similarity with the endocrine factor IFGBP7. The mRNA expression of EsSIBD in different tissues including hepatopancreas, gill, gonad, muscle, heart and haemocytes, and the temporal expression in haemocytes challenged by Listonella anguillarum were measured by real-time RT-PCR. EsSIBD mRNA transcripts could be detected in all examined tissues with the highest expression level in gill. The EsSIBD mRNA expression in haemocytes was sensitive to L. anguillarum stimulation and it was up-regulated from 3 to 24 h after challenge. The structure conservation and functional similarity to IFGBPs, and its sensitivity to L. anguillarum stimulation collectively implied that EsSIBD was probably involved in endocrine and immune systems of Chinese mitten crab, and provided insight into the cross-talk between the invertebrate endocrine and immune system. © 2009 Elsevier Ltd. All rights reserved.

Pan H.,Tianjin Agricultural College | Liu D.,Tianjin Agricultural College | Hu N.,Sinopec | Shi J.,Tianjin Agricultural College | Liu H.-X.,Tianjin Agricultural College
Colloid and Polymer Science | Year: 2015

A series of spherical gold nanoparticles (AuNPs) stabilized by amphiphilic hyperbranched polymers, which have a hydrophilic hyperbranched polyethylenimine core and a hydrophobic shell formed by many long acidamide chains such as saturated palmitamide, octadecanamide, and unsaturated oleamide chains, were prepared by chemical reduction. The effect of the kinds and the ratio of the aliphatic chain in amphiphilic polymers, the amount of the amphiphilic polymers, and the storage time on their size, solubility, and stability in chloroform, toluene, petroleum ether, and n-butyl acetate was investigated by TEM, UV-vis. The results revealed that a high-concentration polymer with a double bond can greatly improve the organic solubility and stability of the AuNPs in the toluene, petroleum ether, and n-butyl acetate. All the AuNPs in different solvents could be used as highly efficient catalysts for the biphasic catalytic reduction of 4-nitrophenol. The effect of the concentration of AuNPs and the capping polymers, the volume of organic phase, and temperature on the turnover number (TON) values of AuNPs is also studied. Their TON values could be enhanced by the AuNPs capped with more polymers or selecting a good solvent. The maximum TON values of the AuNPs in different solvents are about 5040 which has never been reported in the heterogeneous catalytic reduction of 4-nitrophenol. © 2015, Springer-Verlag Berlin Heidelberg.

Yan Z.-L.,Tianjin Agricultural College | Shi J.,Tianjin Agricultural College
Asian Journal of Chemistry | Year: 2012

Ce 0.9Pr 0.1O 2-d mixed oxide was prepared by citrate sol-gel, decomposition of nitrate and coprecipitation methods. The effect of preparation methods on catalytic activity for CO has been investigated. The mixed oxide prepared by citrate sol-gel method has the best CO oxidation activity.

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