Effects of Nitrogen on Work Hardening Behavior of Austenitic High Nitrogen Steel

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Effects of Nitrogen on Deformation Behavior of Austenite High Nitrogen Steel

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Development of High Strength Mg Alloys with Good Formability at Room Temperature

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Enhancing the anti-biofilm activity of 5-aryl-2-aminoimidazoles through nature inspired dimerisation

The increased tolerance of biofilms against disinfectants and antibiotics has stimulated research into new methods of biofilm prevention and eradication. In our previous work, we have identified the 5-aryl-2-aminoimidazole core as a scaffold that demonstrates preventive activity against biofilm formation of a broad range of bacterial and fungal species. Inspired by the dimeric nature of natural 2-aminoimidazoles of the oroidin family, we investigated the potential of dimers of our decorated 5-aryl-2-aminoimidazoles as biofilm inhibitors. A synthetic approach towards 2-aminoimidazole dimers linked by an alkyl chain was developed and a total of 48 dimers were synthesized. The linkers were introduced at two different positions, the N1-position or the N2-position, and the linker length and the substitution of the 5-phenyl ring (H, F, Cl, Br) were varied. Although, no clear correlation between linker length and biofilm inhibition was observed, a strong increase in anti-biofilm activity for almost all N1,N1′-linked dimers was obtained, compared to the respective monomers against Salmonella Typhimurium, Escherichia coli and Staphylococcus aureus. The N2,N2′-linked dimers, having a H- or F-substitution, were also found to show a strong increase in anti-biofilm activity compared to the respective monomers against these three bacterial species and against Pseudomonas aeruginosa. In addition, the obtained growth measurements suggest a broad concentration range with specific biofilm inhibition and no effect on the planktonic growth against Salmonella Typhimurium and Pseudomonas aeruginosa. © 201

Enhancing the anti-biofilm activity of 5-aryl-2-aminoimidazoles through nature inspired dimerisation

The increased tolerance of biofilms against disinfectants and antibiotics has stimulated research into new methods of biofilm prevention and eradication. In our previous work, we have identified the 5-aryl-2-aminoimidazole core as a scaffold that demonstrates preventive activity against biofilm formation of a broad range of bacterial and fungal species. Inspired by the dimeric nature of natural 2-aminoimidazoles of the oroidin family, we investigated the potential of dimers of our decorated 5-aryl-2-aminoimidazoles as biofilm inhibitors. A synthetic approach towards 2-aminoimidazole dimers linked by an alkyl chain was developed and a total of 48 dimers were synthesized. The linkers were introduced at two different positions, the N1-position or the N2-position, and the linker length and the substitution of the 5-phenyl ring (H, F, Cl, Br) were varied. Although, no clear correlation between linker length and biofilm inhibition was observed, a strong increase in anti-biofilm activity for almost all N1,N1′-linked dimers was obtained, compared to the respective monomers against Salmonella Typhimurium, Escherichia coli and Staphylococcus aureus. The N2,N2′-linked dimers, having a H- or F-substitution, were also found to show a strong increase in anti-biofilm activity compared to the respective monomers against these three bacterial species and against Pseudomonas aeruginosa. In addition, the obtained growth measurements suggest a broad concentration range with specific biofilm inhibition and no effect on the planktonic growth against Salmonella Typhimurium and Pseudomonas aeruginosa. © 201

Management of Phytophthora palmivora disease in Citrus reticulata with chemical fungicides

Over 200,000 ha of citrus are grown in Vietnam, and many orchards have been impacted by Phytophthora disease, leading to tree decline and death. Phytophthora palmivora has recently emerged as a serious problem in mandarin (Citrus reticulata) orchards in northern Vietnam, and producers are looking for management solutions. Therefore, we evaluated the efficacy of a range of commercial fungicides and biological agents on the growth of P. palmivora in vitro and for P. palmivora disease management in 6-month-old C. reticulata seedlings and in a 2-year-old C. reticulata orchard. In the in vitro experiment, potassium phosphonate, metalaxyl-M, mancozeb, and Trichoderma viride strongly inhibited the growth of P. palmivora. For diseased seedlings, the percentage recovery of seedlings 50 days after being treated with metalaxyl-M was 70.9%, potassium phosphonate, 69.1%, and mancozeb 57.1%. The percentage recovery of mandarin trees declining from P. palmivora in the orchard 6 months after the first application of potassium phosphonate was 50.0%, metalaxyl-M 45.9%, and mancozeb 30.6%