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The ecological risks and health hazards of heavy metals pollution in Taihu Lake have received widespread concern. This study has developed a species-pollution dataset which includes a large amount of data on heavy metal pollution in Taihu fish. The heavy metal contamination poses a significant threat to human consumption, but no studies have been conducted to assess the risk of exposure to consumption of these fish and to make recommendations for their consumption. In this study, we systematically integrated the relevant data in the dataset, analyzed its contamination level using PI (single pollution index) and MPI (metal pollution index) models, and assessed health hazards of fish consumption using THQ (target hazard quotient) and ILCR (incremental lifetime cancer risk) models. Results showed that the contamination levels of heavy metals in fish varied in a feeding habit and living habit dependent manner. The risk of non-cancer health is the highest from consuming omnivorous fish, then from carnivorous and herbivorous fish. The ILCR model predicted that the long-term Taihu consumption of omnivorous fish may pose a potential carcinogenic risk, especially for children. In all, our study provided a comprehensive understanding on the risk of heavy metals in Taihu. Accordingly, it is recommended that children should try to choose herbivorous fish when consuming fish from Taihu Lake while avoiding long-term consumption of omnivorous fish.

Exchange of mobile functional genes within microbiota benefits the microbial community. However, the status of the mobile gene pool in environment is still largely unclear, impeding the understanding on the process of gene transfer in natural microbial communities. The release of extracellular vesicles (EVs) by diverse organisms has been proposed to be a vital way in the complex networks of interactions between microbes and their habitats. In this study, we hypothesized that microbial EVs encapsulating functional DNA are widely distributed in the environmental matrix. The prevalence, source and DNA cargoes of EVs in three types of typical microbial habitats were studied. High abundance of EVs comparable to the bacterial concentration was found in human faeces, wastewater and soil. Metagenomic analysis showed the diverse and differential taxonomy of EVs-associated DNA compared to source microbiome. An array of efficient EVs producing species was identified. A wide variety of mobile genes including glycoside hydrolase family 25 were enriched. Antibiotic resistance genes co-localizing with mobile genetic elements were abundant in the EVs. This study provides novel insights into the prevalent EVs as a reservoir for the mobile functional genes in the natural environment.

We report on the lattice structures and optical properties of Ce:LYSO crystal waveguides implanted with C, Si and Cu ions at 6 MeV. SRIM software was used to reconstruct the elastic collisions between the implanted ions and target nuclei. The maximum structural changes were induced by the Cu-ion implantation, as determined by XRD and Raman spectra. Photoluminescent and absorption spectra were used to study the optical properties of Ce3+ ions in the Ce:LYSO waveguides. Prism-coupling and end-face coupling methods, respectively, were used to measure the guiding modes and the near-field intensity distribution of light at 633 nm. Typical well + barrier waveguides were formed in the Ce:LYSO crystals implanted by C, Si and Cu ions, which will be a interest application in integrated optical devices.

This chapter firstly traces the legal foundation of right to water to concretize States’ human right obligations and explores potential conflicts between the right to water and service liberalization commitments. This chapter, by looking to the structure of GATS, will argue that the right to regulate should be a channel linking members' human right obligations and their commitments under GATS. In this context, this chapter will attempt to resolve potential conflicts by means of an interpretative approach informed by the dual nature of right to regulate, with particular emphasis on deference to national regulators. Emphasizing the different natures of the right to regulate in human rights and trade law, this chapter suggests that the right to regulate under GATS can bridge WTO members’ obligation to guarantee the right to water in a liberalized water services market, and the object of higher levels of trade liberalization, including basic services.

Underwater acoustic channel is characterized by strictly limited frequency bandwidth, therefore, pulse shaping filter is often used in the transmitter of underwater acoustic (UWA) communication system for baseband processing in order to reduce the inter-symbol interference (ISI), ensure more effective transmission, reduce bit error rate and improve the communication quality. This paper analyses the basic parameters of the pulse shaping filter for UWA coherent communication system and presents one implementation architecture on field programmable gate array (FPGA). The design adopts polyphase structure based on distributed algorithm (DA) and realizes an adjustable roll-off factor shaping filter with greatly reduced resource usage, which is optimized through approach of look-up table (LUT) partition and symmetry of finite impulse response (FIR). The designed shaping filter has been successfully applied to a real time UWA communication system and the results show that it can meet the shaping requirements well.

To identify the gene (s) related to the antagonistic activity of Enterobacter cloacae B8 and to elucidate its antagonistic mechanism.Transposon-mediated mutagenesis and tagging method and cassette PCR-based chromosomal walking method were adopted to isolate the mutant strain(s) of B8 that lost the antagonistic activity and to clone DNA fragments around Tn5 insertion site. Sequence compiling and open reading frame (ORF) finding were done with DNAStar program and homologous sequence and conserved domain searches were performed with BlastN or BlastP programs at www.ncbi.nlm.nih.gov. To verify the gene involved in the antagonistic activity, complementation of a full-length clone of the anrF gene to the mutant B8F strain was used.A 3 321 bp contig around the Tn5 insertion site was obtained and an ORF of 2 634 bp in length designated as anrF gene encoding for a 877 aa polyketide synthase-like protein was identified. It had a homology of 83% at the nucleotide level and 79% ID/87% SIM at the protein level, to the admM gene of Pantoea agglomerans andrimid biosynthetic gene cluster (AY192157). The Tn5 was inserted at 2 420 bp of the gene corresponding to the COG3319 (the thioesterase domain of type I polyketide synthase) coding region on B8F. The antagonistic activity against Xanthomonas oryzae pv. oryzae was resumed with complementation of the full-length anrF gene to the mutant B8F.The anrF gene obtained is related to the antagonistic activity of B8, and the antagonistic substances produced by B8 are andrimid and/or its analogs.

To understand the antagonistic mechanism of the broad spectrum antagonistic Enterobacter cloacae B8, Tn5 transposon-mediated mutagenesis is performed using suicide plasmid pZJ25. Two mutant strains that lost antagonistic character are isolated. Tagging with kan r gene on Tn5, an antagonistic related DNA fragment, the F fragment, right of the Tn5 insertion site is cloned in a plasmid named pTLF, from one of the mutant strains B8F. The 735 bp F fragment is then sequenced after subcloning. Genomic DNA of the original B8 strain is isolated, digested with Pst I and ligated to Pst I cassette. DNA fragments left and right of the F fragment are amplified from the Pst I cassette library using cassette primer and specific primers designed according to known sequence. 1106 bp sequence left of the F fragment and 664bp sequence right of the F fragment are finally obtained. Bioinformatics analysis shows that the contig assembled from the sequences of the cloned antagonistic related DNA fragments of B8 encodes three ORFs and is homogeneous to admM, admN and admO genes of Pantoea agglomerans andrimid biosynthetic gene cluster (AY192157). The ORF, named anrF gene which encodes a polyketide synthase, knocked out by Tn5 insertion, is a homology of admM and the insertion site of Tn5 is at 214 bp upstream of the stop codon. It is concluded that the anrF gene is a gene related to the antagonistic activity of E. cloacae B8, and speculated that the antagonistic substance produced by B8 is an andrimid.