Search

This article aims to investigate the atmospheric corrosion of carbon steel in a marine environment abundant in hydrogen sulfide (H2S) resulting from the decomposition of Sargassum seaweed. To accomplish this, four sites with varying degrees of impact were chosen along the coast of Martinique. The corrosion rates of steel were evaluated through mass loss measurements. After one year of exposure, the corrosion rates were notably high, particularly in atmospheres rich in Cl− ions and H2S, ranging from 107 µm to 983 µm. Complementing these findings, surface and product morphologies were characterized using scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). These analyses revealed a significant degradation of the corrosion surface in the most affected atmospheres compared to those unaffected by Sargassum seaweed strandings. Lepidocrocite (γFeOOH) was identified as the predominant product regardless of the exposure atmosphere. However, goethite (αFeOOH) was found to be present in atmospheres most impacted by H2S.

Confronting the challenge of biofilm resistance and widespread antimicrobial resistance (AMR), this study emphasizes the need for innovative monitoring methods and explores the potential of bacteriophages against bacterial biofilms. Traditional methods, like optical density (OD) measurements and confocal microscopy, crucial in studying biofilm–virus interactions, often lack real-time monitoring and early detection capabilities, especially for biofilm formation and low bacterial concentrations. Addressing these gaps, we developed a new real-time, label-free radiofrequency sensor for monitoring bacteria and biofilm growth. The sensor, an open-ended coaxial probe, offers enhanced monitoring of bacterial development stages. Tested on a biological model of bacteria and bacteriophages, our results indicate the limitations of traditional OD measurements, influenced by factors like sedimented cell fragments and biofilm formation on well walls. While confocal microscopy provides detailed 3D biofilm architecture, its real-time monitoring application is limited. Our novel approach using radio frequency measurements (300 MHz) overcomes these shortcomings. It facilitates a finer analysis of the dynamic interaction between bacterial populations and phages, detecting real-time subtle changes. This method reveals distinct phases and breakpoints in biofilm formation and virion interaction not captured by conventional techniques. This study underscores the sensor’s potential in detecting irregular viral activity and assessing the efficacy of anti-biofilm treatments, contributing significantly to the understanding of biofilm dynamics. This research is vital in developing effective monitoring tools, guiding therapeutic strategies, and combating AMR.

L’IA ouvre un vaste champ des possibles en architecture et par conséquent dans la formation des architectes. Les craintes et les attentes obligent à bien poser les fondamentaux de ce qui peut former une nouvelle pédagogie intégrant les IA. Cet article rappelle quelques repères, organise les grandes familles des IA pour les architectes et rend compte des premières expériences auprès des étudiants.