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Regular line and circle arry micro-apparatus on 65Mn plate formed by femtosecond direct writting with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130fs in air. Investigate the effect of pulse energy and scan speed. Found, that the increased scan speed was similar to the decreased pulse energy. Due to the circle pattern was different to the line process, the contrary phenomenon appeared, which with increased ablation energy, the width of groove was less and the depth was increased.

Regular micro-apparatus which covered with periodic nano-hole, nano-ridge and ripple structures on silicon bulk were formed by laser micro-machining with tightly focused beam of the femtosecond laser with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130 fs in air. The periodic nano-hole structures which focus with a 20× focusing objective lens (NA = 0.4) is reported. Investigating the relationship between the width of structures and the speed of processing.

An aqueduct of larger-span prestressed concrete arch structure for river diversion project is located in coastal areas, and raises difficult questions on deformation and stability control of the construction process due to greater wind load and poor soil. Due to the limited width of bracket erection, this paper put forward five possible construction schemes, and does the comparative analysis using three-dimensional finite element program, and gets the economic and reasonable one. Finally conduct a pressure test after the bracket erection, and verify the analysis results using measured stress and deformation data.

We calculate the temperature of excited plasma, found that will be enhanced with pulse energy increased. The delay time and the pulse energy were very important to the LIBS signal and define the -0.5μs was very suitable to this experiment, determined the intensity of emission spectra was linear to the pulse energy when the delay time was fixed. By change the delay time, got the emission of bivalence ionization of Zn was just less than 500ns.At last, we had researched the effect of element concentration and the thickness of film on signal intensity. When the concentration of Al being increased from 2.5% to 5%, the intensity of signal enhanced double. At the same time the content of Zn being decreased from 78% to 76%, the intensity of signal had just no change.

AIM: To apply a new, integrated technique for visualizing bacterial genomes to identify novel pathogenicity islands in Helicobacter pylori (H. pylori). METHODS: A genomic barcode imaging method (converting frequency matrices to grey-scale levels) was designed to visually distinguish origin-specific genomic regions in H. pylori. The complete genome sequences of the six H. pylori strains published in the National Center for Biotechnological Information prokaryotic genome database were scanned, and compared to the genome barcodes of Escherichia coli (E. coli) O157:H7 strain EDL933 and a random nucleotide sequence. The following criteria were applied to identify potential pathogenicity islands (PAIs): (1) barcode distance distinct from that of the general background; (2) length greater than 10000 continuous base pairs; and (3) containing genes with known virulence-related functions (as determined by PfamScan and Blast2GO). RESULTS: Comparison of the barcode images generated for the 26695, HPAG1, J99, Shi470, G27 and P12 H. pylori genomes with those for the E. coli and random sequence controls revealed that H. pylori genomes contained fewer anomalous regions. Among the H. pylori-specific continuous anomalous regions (longer than 20 kbp in each strain’s genome), two fit the criteria for identifying candidate PAIs. The bioinformatic-based functional analyses revealed that one of the two anomalous regions was the known pathogenicity island cag-PAI, this finding also served as proof-of-principle for the utility of the genomic barcoding approach for identifying PAIs, and characterized the other as a novel PAI, which was designated as tfs3-PAI. Furthermore, the cag-PAI and tfs3-PAI harbored genes encoding type IV secretion system proteins and were predicted to have potential for functional synergy. CONCLUSION: Genomic barcode imaging represents an effective bioinformatic-based approach for scanning bacterial genomes, such as H. pylori, to identify candidate PAIs.