Synthesis of 3,6-Divinyl-1,2,4,5-Tetrazine, the First Member of the Elusive Vinyltetrazine Family

International audienceThe synthesis of the first vinyltetrazine derivative is ­described. 3,6-Divinyl-1,2,4,5-tetrazine was obtained following a methodology involving cyclization from an imidate and use of 2-phenylsulfonylethyl groups as masked vinyl entities. The first properties of this unique compound are reported

Pressure Ulcers and Dressings: A Strain Sensitivity Analysis of the Boundary Conditions of a Finite Element Model

Recently, a new bi-layer dressing was proposed by Urgo RID to reduce the healing time of pressure ulcers (PU). This dressing was numerically evaluated in previously published work. In the current work, the influence on the maximal shear strains of modelling parameters such as the dressing local geometry, the pressure applied by the gauze inside the wound, the wound deepness, and the mattress stiffness, was assessed. A sensitivity analysis was performed on these four parameters. Among all experiments, the mean maximal Green--Lagrange shear strain was 0.29. The gauze pressure explained 60% of the model response in terms of the volume of tissues under strains of 0.3, while the wound deepness explained 28%. The mattress had a significant, but low impact, whereas the dressing local geometry had no significant impact. As expected, the wound deepness was one of the most influential parameters. The gauze turned out to be more significant than expected. This may be explained by the large range of values chosen for this study. The results should be extended to more subjects, but still suggest that the gauze is a parameter that might not be neglected. Care should also be taken in clinical practice when using gauze that could have either a positive or negative impact on the soft tissues' strains. This may also depend on the wound deepness

PREMIERE SYNTHESE TOTALE D'ANALOGUES PHENYLPYRIDINIQUES DU RHAZINILAME

ROUEN-BU Sciences (764512102) / SudocROUEN-INSA Madrillet (765752301) / SudocSudocFranceF

Comparison of fluorescence and QCM technologies: Example of explosives detection with a pi-conjugated thin film

International audienceA pi-conjugated compound was synthesized as a sensitive material for explosives detection. The detection of vapors of 2,4-dinitrotoluene was demonstrated with quartz crystal microbalance (QCM) and fluorescence transduction methods. The fluorescence intensity monitoring shows a higher sensitivity and selectivity than the monitoring of the QCM frequency. Both methods appear to be synergic when used simultaneously as the sensor helps to discriminate interferent vapors from nitroaromatics

Adsorption of functionalised thiols on gold surfaces: how to build a sensitive and selective sensor for a nitroaromatic compound?

Adsorption of thiols of varying structures bearing amine, acid or aromatic functionalities was characterised by Polarisation Modulation Infrared Absorption Spectroscopy (PM-IRRAS). The so functionalised surfaces were then submitted to atmospheres containing traces of 2,4-dinitrotrifluoromethoxybenzene and gas capture was evaluated by Quartz Crystal Microbalance (QCM). The selectivity of these new sensors was also evaluated thanks to exposures to solvents: ethanol, methylethylketone, toluene and dichloromethane. The QCM response appeared to be the best one, high and specific to the nitroaromatic, for aromatic amine functions