Comparison of bevel and tulip triggered pultruded tubes for energy absorption

The crushing behavior of E-glass/polyester and E-glass/vinyl ester pultruded tubes has been found to be significantly different for tulip triggered specimens as compared with bevel triggered specimens. Up to 100% more energy per unit weight was absorbed by tulip triggered tubes. In addition, the crushing was more controlled and predictable with the tulip trigger. The morphology of the material in the crushing zone differed in the amount and the pattern of fracture. The fracture pattern and crushing behavior initiated by both triggers were found not to change during crushing. The difference in crushing appeared to arise from the different abilities of the tubes to support load because of the different geometry of individual load-carrying structures that resulted from triggering.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29526/1/0000613.pd

Metabolic synergies in the biotransformation of organic and metallic toxic compounds by a saprotrophic soil fungus

The saprotrophic fungus Penicillium griseofulvum was chosen as model organism to study responses to a mixture of hexachlorocyclohexane (HCH) isomers (α-HCH, β-HCH, γ-HCH, δ-HCH) and of potentially toxic metals (vanadium, lead) in solid and liquid media. The P. griseofulvum FBL 500 strain was isolated from polluted soil containing high concentrations of HCH isomers and potentially toxic elements (Pb, V). Experiments were performed in order to analyse the tolerance/resistance of this fungus to xenobiotics, and to shed further light on fungal potential in inorganic and organic biotransformations. The aim was to examine the ecological and bioremedial potential of this fungus verifying the presence of mechanisms that allow it to transform HCH isomers and metals under different, extreme, test conditions. To our knowledge, this work is the first to provide evidence on the biotransformation of HCH mixtures, in combination with toxic metals, by a saprotrophic non-white-rot fungus and on the metabolic synergies involved

Preliminary study of substrate binding to thymidine kinase by transferred NOE

A series of substrates with different values of dissociation constants Kd characteristic of their interaction with thymidine kinase (TK) has been studied (thymidine, acyclovir and tricycle). In thymidine-TK solutions no transferred NOEs were observed which was attributed to the fact that the dissociation constant Kd is too low (~8 µm). In both acyclovir and tricycle, however, Kd proved sufficiently high (~400 µM) to allow for the observation of negative (transferred) NOEs. Series of NOESY spectra were recorded for tricycle (positive NOEs) and for the tricycle-TK complex (negative NOEs). The NOE pattern remains the same in both cases which indicates that the structure of the ligand does not change significantly upon binding to TK. The analysis of correlation patterns proves that the orientation of the aliphatic chain of tricycle with respect to the aromatic rings is characteristic of the syn conformation

Non-Axial Crushing of E-Glass/Polyester Pultruded Tubes

Two types of non-axial crushing, off-axis crushing and angled crushing, have been identified and significant differences found between the E-glass/polyester pultruded tubes crushed in these different configurations. Energy absorption for the two types of crushing was found also to vary significantly with the angle of inclination, with the difference being largest at high angles of inclination. Reasons for energy absorption differences between the crushing configurations include the initiation of different crack patterns, different loading of individual fibers, and altered friction. For all angles, the load required for continued crushing was found to fluctuate more for off-axis crushing than for angled crushing.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67836/2/10.1177_002199839002401004.pd