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Chang G.,CAS Institute of Zoology | Chang G.,Shaanxi Normal University | Chang G.,Shaanxi Institute of Zoology | Zhang Z.,CAS Institute of Zoology
Acta Oecologica | Year: 2011

Seed hoarding is an important behavioral adaptation to food shortages for many rodent species. Sympatric rodents may affect the natural regeneration of large-seeded trees differently as seed dispersers or seed predators. Using seeds of oil tea (Camellia oleifera), we investigated differences in hoarding behaviors among six sympatric rodent species in semi-natural enclosures in a subtropical forest in southwest of China. We found that all these six species ate seeds of C. oleifera, but only Edward's long-tailed rats (Leopoldamys edwardsi) were predominantly scatter hoarders; chestnut rats (Niviventer fulvescens) and white-bellied rats (Niviventer confucianus) scatter hoarded and larder hoarded few seeds, but were seed predators; South China field mice (Apodemus draco) exhibited little larder-hoarding behavior; and Chevrier's field mice (A. chevrieri) as well as Himalayan rats (Rattus nitidusa) did not hoard seeds at all. The rodents that engaged in scatter hoarding often formed single-seed caches and tended to cache seeds under grass or shrubs. Our findings indicate that sympatric rodents consuming seeds of the same species of plant can have different hoarding strategies, affecting seed dispersal and plant regeneration differently. We conclude by discussing the role of these species in hoarding seeds of C. oleifera and highlight the essential role of Edward's long-tailed rats as predominantly potential dispersers of this plant species. © 2011 Elsevier Masson SAS. Source

Yang C.,Shaanxi Institute of Zoology
Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji | Year: 2012

The complete sequence of mitochondrial genome of Larus brunnicephalus was determined using long PCR and conserved primers walking approaches. The results showed that the entire mitochondrial genome of L. brunnicephalus is 16,769 bp in length, which has been deposited in GenBank with the accession number JX155863. The mitochondrial genomic organization and gene order of L. brunnicephalus were consistent with that of Gallus gallus, which contains 13 protein coding genes (PCGs), 22 tRNA, 2 rRNA, and a control region. Except for COI gene using GTG and ND3 gene with ATT as the initiation codon, all other 11 PCGs of the mtDNA in L. brunnicephalus started with the typical ATG codon. AGG, TAG, TAA, or AGA were used in 11 PCGs as usual termination codons, except for COIII and ND4 genes with incomplete termination codon (T). The secondary structures of 22 tRNAs were predicted and it is found that the tRNASer (AGN) lacks DHU arm and tRNAPhe contains the fourth types of permutation in the TψC arm. It is predicted that the secondary structures of 12S rRNA and 16S rRNA include 4 structural domains with 47 helics and 6 domains with 60 helics, respectively. F-box, E-box, D-box, C-box, B-box, Bird similarity-box, and CSB-boxes (1-3), which were found in the control regions of other bird species were also present in L. brunnicephalus. The sequence in the starting regions of H-strand replication (OH) and the bidirectional light and heavy-strand transcription promoters (LSP/HSP) in the control region were also predicted. Result of phylogeny analysis supports that L. brunnicephalus should be categorized into the Masked gulls species. Source

Chang G.,CAS Institute of Zoology | Chang G.,Shaanxi Institute of Zoology | Zhang Z.,CAS Institute of Zoology
Acta Oecologica | Year: 2014

Network structure in plant-animal systems has been widely investigated but the roles of functional traits of plants and animals in formation of mutualism and predation interactions and community structure are still not fully understood. In this study, we quantitatively assessed interaction strength of mutualism and predation between 5 tree species and 7 rodent species by using semi-natural enclosures in a subtropical forest in southwest China. Seeds with high handling-time and nutrition traits (for both rat and mouse species) or high tannin trait (for mouse species) show high mutualism but low predation with rodents; while seeds with low handling-time and low nutrition traits show high predation but low mutualism with rodents. Large-sized rat species are more linked to seeds with high handling-time and high nutrition traits, while small-sized mouse species are more connected with seeds with low handling-time, low nutrition value and high tannin traits. Anti-predation seed traits tend to increase chance of mutualism instead of reducing predation by rodents, suggesting formation of mutualism may be connected with that of predation. Our study demonstrates that seed and animal traits play significant roles in the formation of mutualism and predation and network structure of the seed-rodent dispersal system. © 2013 Elsevier Masson SAS. Source

Jin M.,Northwestern Polytechnical University | Zhao K.,Shaanxi Institute of Zoology | Huang Q.,Northwestern Polytechnical University | Shang P.,Northwestern Polytechnical University
International Journal of Biological Macromolecules | Year: 2014

Recently, a great deal of interest has been developed to isolate and investigate novel bioactive components with health benefit effects from natural resources. The dried root of Astragalus membranaceus, one of the most popular health-promoting herbal medicines, has been used historically as an immunomodulating agent for the treatment of common cold, diarrhea, fatigue and anorexia for more than 2000 years. Modern phytochemistry and pharmacological experiments have proved that polysaccharide is one of the major active ingredients in the root of A. membranaceus with various important bioactivities, such as immunomodulation, antioxidant, antitumor, anti-diabetes, antiviral, hepatoprotection, anti-inflammation, anti-atherosclerosis, hematopoiesis and neuroprotection. The aim of the present review is to summarize previous and current references and give a comprehensive summary regarding the structural features and biological activities of A. membranaceus polysaccharides in order to provide new insight for further development of these macromolecules. © 2013 Elsevier B.V. Source

Shen W.,Xian University of Science and Technology | Feng L.,Xian University of Science and Technology | Feng H.,Shaanxi Institute of Zoology | Lei A.,Xian University of Science and Technology
Ceramics International | Year: 2013

To produce better antibacterial and low water-soluble submicron powders of divalent silver oxide (AgO), divalent silver oxide-diatomite (AgO-d) hybrids were studied. AgO-d hybrids were prepared by chemical oxidation, using silver nitrate and diatomite as raw materials and potassium persulfate as oxidant. The results show that AgO-d hybrids with AgO weight percentage up to 20.8% are obtained by oxidation of Ag+ adsorbing on diatomite in alkaline solution (n(KOH)/n(AgNO3)=7.5) for 1.5 h at 333.15 K. Products were characterized by laser particle sizer, SEM, XRD, XPS, FT-IR and atomic absorption spectrophotometer (AAS). AgO-d hybrids are composed of tetragonal cristobalite, amorphous silica, monoclinic divalent silver oxide and a few of cubic silver oxide. Element Ag can be released from AgO-d hybrids but the dissolution speed is slow, which is about 3.20×10-2 mg (L h)-1. Antibacterial effectiveness of AgO-d hybrids was tested against Staphylococcus aureus (S. aureus ATCC6538) and Escherichia coli (E. coli ATCC8099) by the shake-flask method. Results show that AgO-d hybrids possess excellent antibacterial properties. When the concentration of AgO-d hybrids is 10 mg L-1 and the contact time with S. aureus and E. coli is 30 min, the bactericidal rates reach up to 99.974% and 99.944%, respectively. © 2013 Elsevier Ltd and Techna Group S.r.l. Source

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