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The primary objective of this research study was to evaluate the capabilities for measuring strain of a composite UAV wing with an embedded optical fiber connected to a Rayleigh backscattering distributed sensing system. This research paper summarizes the manufacturing procedure used during the instrumentation of the composite UAV wing. In addition, a Finite Element Model was developed in order to verify the strain distribution of this complex structure under static and dynamic loading conditions. The use of strain gauge data as a means for verification is presented as part of this research. Finally, fatigue tests were carried out to determine the longevity of the embedded fiber during the design life of the structure. The results demonstrate the ability of a distributed sensing system to obtain complex and accurate strain distributions on a single non-grated fiber. In addition, the findings demonstrate current limitations of the system for capturing accurate strain profiles in dynamic loading test cases.

Four AS-48 mutants (Trp24Ala, Gly13Lys, Leu40Lys and Ala53Ser) were obtained by site-directed mutagenesis. The minimal inhibitory concentration of each peptide showed that only residue Trp24 was unquestionably involved in the biological activity. Guanidine hydrochloride-induced unfolding assays showed a three-state transition denaturation process, suggesting a molten-globule-like conformation after the first transition.

The complete primary structure of the peptide antibiotic AS-48 produced by Enterococcus faecalishas been determined by chemical degradation analysis. The cyclic nature of this 70 residues containing peptide was demonstrated by plasma desorption mass analysis of the generated peptides and electrospray ionisation mass analysis of the native polypeptide. As far as we know, this is the first example of an antibiotic protein cyclised by a tail—head peptide bond formation and not by branching of the polypeptide side chains.

The complete primary structure of the peptide antibiotic AS‐48 produced by Enterococcus faecalishas been determined by chemical degradation analysis. The cyclic nature of this 70 residues containing peptide was demonstrated by plasma desorption mass analysis of the generated peptides and electrospray ionisation mass analysis of the native polypeptide. As far as we know, this is the first example of an antibiotic protein cyclised by a tail—head peptide bond formation and not by branching of the polypeptide side chains.

?????Three antibiotic peptides with amoebolytic activity have been purified from culture supernatants of Bacillus licheniformis M-4 (amoebicins m4-A, m4-B, and m4-C). They were hydrophilic peptides consisting of six different amino acids (Asp, Glu, Ser, Thr, Pro, Tyr). Their molecular weights ranged from 3,000 to 3,200. Purified amoebicins were active against human pathogenic and non-pathogenic strains of Naegle ria. They also showed a broad antifungal spectrum, but a narrow antibacterial activity.

ABSTRACTTwo plasmid-derived NcoI DNA fragments of 14 and 4.5 kb, respectively, have been isolated from the multidrug-resistant strain Enterococcus hiraeS185R and analyzed. The 14-kb fragment contains two inverted (Land R) IS1216insertion modules of the ISS1family. These modules define a Tn5466transposon-like structure that contains one copy of the methylase-encoding ermAMconferring erythromycin resistance and one copy of the adenylyl-transferase-encoding aadEconferring streptomycin resistance. Immediately on the left side of IS1216Lthere occurs a copy of pbp3rencoding the low-affinity penicillin-binding protein (PBP) PBP3r, itself preceded by apsr-like gene (psr3r) that controls the synthesis of PBP3r. ermAM, aadE, and the transposase gene (tnp) of IS1216Rhave the same polarities, and these are opposite those of psr3r,pbp3r, and the tnpgene of IS1216L. The 4.5-kb fragment is a copy of the 4.5-kb sequence at the 5′ end of the 14-kb fragment, although it is not a restriction product of the 14-kb fragment. It contains three genes with the same polarity:psr3r, pbp3r, and tnpin an IS1216element. Because of the very high degree of identity (99%) with the chromosomal psrfmand pbp5fmgenes of Enterococcus faeciumD63R, it is proposed that both the psr3rand pbp3rgenes were transferred from an E. faeciumstrain and inserted in a plasmid ofE. hirae. E. hiraeis the first known bacterial species in which a low-affinity PBP-encoding gene has been found to be plasmid borne.