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The NiTi claddings by tungsten inert gas (TIG) with Ni and Cu interlayer were manufactured to resist the cavitation erosion-corrosion (CEC). The cavitation test, the open circuit potential and the potentiodynamic polarization measurements were used to study the synergistic effect among cavitation erosion (CE) and corrosion for the NiTi claddings. After the CEC test for 11[Formula: see text]h, the cumulative mass loss of 304 stainless steel is 5 and 1.15 times that of NiTi-Ni-TIG cladding and NiTi-Cu-TIG cladding, respectively. In NiTi-Cu-TIG cladding, the galvanic corrosion between the Cu-Ti intermetallics and the B2 phase causes the anodic dissolution of the Cu-Ti intermetallics, and results in the B2 phase losing support and spalling off during the CEC test. In contrast, NiTi-Ni-TIG cladding can be used against the CEC because of its uniform microstructure, no Cu-rich area and the effect of corrosion on CE of NiTi-Ni-TIG cladding is small.

Highly efficient and dependable large-scale DDoS attack detection scheme is critical for network anomaly detection. Typical machine learning algorithms such as Decision Tree and Adaboost work well on flow level analysis but cannot perform fine- grained detection of packet levels. Since these algorithms require more packets information for detection, resulting in higher detection delay and relatively lower accuracy. To address the problem, we propose DeepDDoS which is a deep learning method focusing on both period- wise and packetwise attack detection. First, the network packets are modeled in time dimension to discover the potential abnormal time period. Second, the network packets are grouped by 5 tuples (flow), the packets inside the group are sorted according to their arrival time. Then the data packet level sequence modeling is performed in each group. Comprehensive performance evaluation shows that the detection accuracy of DeepDDoS reach 99%. Furthermore, only 5 consecutive packets are needed for packet-wise detection, greatly reducing detection delay and computational overhead. Comparative experiments show that DeepDDoS outperforms existing typical attack detection methods

To reveal the relationship between Deuteromycetes community and the environmental in Kiaochow Bay of the Yellow Sea.Using recorded pollution survey, we used molecular methods to study seasonal and spatial variation of Deuteromycetes community diversity in different polluted waters of Kiaochow Bay of the Yellow Sea, China.Denaturing gradient gel electrophoresis fingerprints varied obviously among different sites of similar level of pollution. Moreover, sequence analysis of recovered dominant bands exhibited the existence of plenty of uncultivable fungi, among which Penicillium was the dominant genus. Furthermore, in heavily polluted estuary, there were abundant animal pathogens such as amoeba and Pythium as well as Deuteromycetes. These discoveries demonstrate that the Deuteromycetes community structure is closely related to marine environment, and are indicative of different level of marine contamination.The relationship between Deuteromycetes community and different level of pollution and seasons varied were closely related.

Indolocarbazole (ICZ) alkaloid constitutes a group of natural products which manifested powerful biological activity, especially anticancer. However, it was laborious to find ICZs-yield organism when anticancer activity was adopted as selection target. The specificity of 6 primer pairs was detected and the results revealed that primer rebBN1/rebBC1 possessed preferable specificity because indolocarbazole-producers DNA was exclusively amplified and no target fragment was amplified from any of indolocarbazole nonproducers. Therefore, primer rebBN1/rebBC1 could specifically identify indolocarbazole-producers from microorganism strains. Key words: Indolocarbazole, rebBN1/rebBC1, ICZs-producing microorganism screening.

Chemical examination of an arctic actinomycete Streptomyces nitrosporeus resulted in the isolation of two new alkaloids named nitrosporeusines A (1) and B (2), an unprecedented skeleton containing benzenecarbothioc cyclopenta[c]pyrrole-1,3-dione. Their structures were determined through extensive spectroscopic analyses in association with X-ray single crystal diffraction. Both 1 and 2 exhibited inhibitory activities against the H1N1 virus in MDCK cells.

 Actinomycetes represent a valuable source of commercially significant antibiotics. However, the yields of antibiotics in wild Actinomycetes usually could not meet the commercial needs and so antibiotics yield improvement is a constant requirement in the drug industry. Various methods and strategies such as traditional strain breeding methods and fermentation optimization methods have been tried and some new ideas such as gene engineering, mixed culture and quorum sensing along with empirical approaches are still on the way to gain this ultimate goal. This review will focus on the strategies and approaches for Actinomycetes antibiotics augment.Â

The known or suspected hazards of polycyclic aromatic hydrocarbons (PAHs) have provoked enormous concentration and endeavours to relieve or eliminate these precarious compounds from miscellaneous environments including soil, water and air. Among various interventions, biodegradation is an appealing approach for its comparative high efficiency and preferable safety. Microorganisms played crucial role in biodegradation of PAHs. Traditional access mainly including culture-dependent procedures has discovered and isolated PAHs-degrading microorganisms which could be subsequently applied to specific contaminated locus. Although certain progress has been achieved owing to traditional methods, much details in PAHs bioremedation leave pending because of the complexity nature of this process. As the rapid development of biology, molecular techniques such as PCR, fingerprinting technique (mainly DGGE), DNA hybridization technique and gene reporters technique have been intensively applied to gain further insight into the mechanism of PAHs degradation. These techniques not only proved the existence and role of uncultivable microorganisms in the whole population of PAHs degrading related microbials, but also made it possible to revealed the otherwise undetectable complex relationships between multi-microorganism concerned in PAHs biodegradation. Application of such techniques in the field of PAHs biodegradation were reviewed in this article.

Chemical examination of an arctic actinomycete Streptomyces nitrosporeus resulted in the isolation of two new alkaloids named nitrosporeusines A (1) and B (2), an unprecedented skeleton containing benzenecarbothioc cyclopenta[c]pyrrole-1,3-dione. Their structures were determined through extensive spectroscopic analyses in association with X-ray single crystal diffraction. Both 1 and 2 exhibited inhibitory activities against the H1N1 virus in MDCK cells.

We studied the antifungal effect of the metabolite BMME-1 from Bacillus marinus B-9987, to reveal its antifungal mechanism.The permeability of the Alternaria solani was tested by spectrophotometer after the treating the crude extracts of B-9987. The composition of cell wall and the sterol components of the fungal plasmalemma of Alternaria solani were analyzed with Infrared Spectrum and GC-MS, respectively.We found that the metabolites of B-9987 had strong antifungal activity with MIC50 and MFC value being 6.2mg/L and 50mg/L. The absorbance in extracellular fluid detection showed that the tegument of the fungi was impaired. The detection of glucan and chitin indicated the change in the structure of the cell wall. The absorption peak of the carbon-hydrogen bond, beta-glucosidic bond, carbon--oxygen bond was attenuated but the hydroxyl, carbonyl absorption was enhanced on the contrary. There were only one peak change in chitin chromatogram on the absorption of amide linkage comparing to the control. These changes on the structure may affect the stability of the fungal cell wall. Ergosterol was the predominant component of sterol with the proportion of 62.52 +/- 3.31% in control cells, but showed a decline during treatment with BMME-1 at a concentration of 56.36 +/- 2.52%. Accumulation of coprostanol, the precursor of ergosterol, was found in the test.From the result we can conclude that the antifungal mechanism of the crude extracts was interfering of ergosterol synthesis resulting in the change on permeability, and also mainly changed the structure of the cell wall, mainly acting on the glucan synthesis.