ABSTRACT
The metagenome sequencing was used to compare the difference of six soil samples, the rhizosphere soil of the first and the second rotation poplar plantations (RSP1, RSP2), the bulk soil of the first and the second rotation poplar plantations (BSP1, BSP2), the soil of rotated peanut field (RPS) and the abandoned land soil (ALS) after poplar clear cutting, in phosphate-solubili-zing microbial community and abundance of phosphatase gene (PG) in a poplar plantation. The results showed that microorganisms from nine genera were related to phosphorus cycle with Bacillus and Pseudomonas being the dominant. The abundance of PSMs was highest in ALS, followed by RPS, RSP2 and BSP2, RSP1 and BSP1, respectively. There was a significant difference of PSMs among the six soil samples. After poplar clear cutting, the abundance of Bacillus and Pseudomonas in RPS and ALS increased significantly, whereas that of Arthrobacter, Bradyrhizobium and Streptomyces decreased. However, in the rhizosphere soil of poplar plantations, an opposite pattern appeared when comparing RSP2 to RSP1. Bacillus and Pseudomonas were more abundant in rhizosphere soils than in bulk soil, while Arthrobacter, Bradyrhizobium and Streptomyces were higher. The abundance of PG presented the regularity of RSP1 and BSP1 > ALS > RSP2 and BSP2 > RPS. Rhizosphere had a more significant effect in the successive rotation poplar plantations than in the second rotation plantation. An even lower phosphatase gene's abundance was shown in rhizosphere soil than in bulk soil. The number of PSMs was negatively correlated with the content of phenolic acids but positively correlated with pH value.
Subject(s)
Phosphates/metabolism , Populus/microbiology , Rhizosphere , Soil Microbiology , Soil/chemistry , Forestry , PhosphorusABSTRACT
SWNTs are a mixture of 1/3 metallic SWNTs (m-SWNTs) and 2/3 semiconducting SWNTs (s-SWNTs). It is desirable to separate the metallic SWNTs from the semi-conducting ones. In this study m-SWNTs was separated by using a poly[(m-phenylenevinylene)-alt-(p-phenylenevinylene)] (PmPV) derivative and used as photo-thermal media instead of SWNTs. The separation effects of m-SWNTs were evaluated by Raman spectra, molecular modeling and TEM images. The effects of m-SWNTs on MCF-7 cell proliferation and apoptosis were evaluated with MTT assay and flow cytometry, respectively. m-SWNTs were separated with high purity. A strong inhibition of MCF-7 cell growth was observed with the m-SWNTs under near-infrared (NIR) light irradiation. Our results will be helpful for the potential applications of m-SWNTs in clinical photothermal cancer therapy.
Subject(s)
Apoptosis , Breast Neoplasms/pathology , Nanotubes, Carbon , Flow Cytometry , Humans , Light , MCF-7 Cells/drug effects , Models, MolecularABSTRACT
The FTIR (Fourier transform infrared) spectra of benign pleomorphic adenoma tissues and malignant ones were investigated using the spectrometer GX FTIR Spectroscopy. The results indicated that there were infrared spectra difference between the benign adenoma tissues and the malignant ones in some bands. Compared to the benign adenoma tissues, the contents of nucleic acid relative to the collagen protein and the adipose relative to the protein both increase in malignant ones.
