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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.

Abstract Monitoring of atmospheric pollutants is a key point for preventive conservation since these species are known to impact the integrity of many artifacts including metals, papers, pigment and textiles. The problem can be amplified in closed environments, like in exhibition rooms and showcases, where temperature and relative humidity gradients and levels can introduce additional micro-climatic problems. One objective of the EU-SensMat project concerns the development of low cost and low visual nuisance sensors sensitive to these pollutants, making them affordable for all museums including small ones. For this purpose, the Radio-Frequency Identification (RFID) technology was considered to produce air-quality sensors based on reactive metallic dosimeter. Besides the low cost, they can be easily integrated to other existing RFID applications such as identification tasks since the interrogation is made with a commercial UHF-RFID reader. The description and the main features of these sensors are discussed in this paper. Moreover, as it will be shown, the subsequent chemical analysis of the sensitive part of the sensors provide useful information to determine the origin of the pollutants.

Direct information on the dynamic interplay between membrane proteins and lipids is scarce. Here the authors report a detailed description of these close relationships by combining lipid nanodiscs and high-pressure NMR. They report the link between pressure and lipid compositions to the conformational landscape of the β-barrel OmpX and the α-helical BLT2 G Protein-Coupled Receptor in nanodiscs.

The prediction of the metal cluster within a coordination polymer or complex, as well as the dimensionality of the resulting polymer or complex (i.e., 0D, 1D, 2D, or 3D), is often challenging. This is the case for Ph2P(CH2)mPPh2 ligands (1 ≤ m ≤ 8) and CuX salts, particularly for X = I. This work endeavors a systematic statistical analysis combining studies in the literature and new data, mapping the nature of the resulting CuI aggregates with eight different diphoshphines in 2:1, 3:2, 1:1, 2:3, and 1:2 CuI:Ph2P(CH2)mPPh2 molar ratios as a function of m, which lead to either pure products or mixtures. Several trends are made relating stoichiometry and chain length to the CuI cluster formed (i.e., globular vs. quasi-planar). Four new X-ray structures were determined: [Cu3I2(L1)3]I, Cu3I3(L2)2, Cu2I2(L6)2, and Cu4I4(L8)2, where m is, respectively, 1, 2, 6, and 8, in which the CuxIy central aggregates adopt triangular bipyramid, diamond, rhomboid, and cubane shaped motifs, respectively. Photophysical measurements assisted the establishment of trends considering the paucity of the crystallographic structures. During this study, it was also found that the 0D-complex Cu2I2(Ph2P(CH2)5PPh2)2 exhibits thermally activated delayed fluorescence.

Artificial Neural Networks (ANNs) have achieved unequaled performance for numerous problems in many areas of Science, Business, Public Policy, and more. While experts are familiar with performance-oriented software and underlying theory, ANNs are difficult to comprehend for non-experts because it requires skills in programming, background in mathematics and knowledge of terminology and concepts. In this work, we release EpyNN, an educational Python resource meant for a public willing to understand key concepts and practical implementation of scalable ANN architectures from concise, homogeneous and idiomatic source code. EpyNN contains an educational Application Programming Interface (API), educational workflows from data preparation to ANN training and a documentation website setting side-by-side code, mathematics, graphical representation and text to facilitate learning and provide teaching material. Overall, EpyNN provides basics in Python for individuals who wish to learn, teach or develop from scratch.

Abstract Background Transposons are mobile genetic elements that colonize genomes and drive their plasticity in all organisms. DNA transposon-encoded transposases bind to the ends of their cognate transposons and catalyze their movement. In some cases, exaptation of transposon genes has allowed novel cellular functions to emerge. The PiggyMac (Pgm) endonuclease of the ciliate Paramecium tetraurelia is a domesticated transposase from the PiggyBac family. It carries a core catalytic domain typical of PiggyBac-related transposases and a short cysteine-rich domain (CRD), flanked by N- and C-terminal extensions. During sexual processes Pgm catalyzes programmed genome rearrangements (PGR) that eliminate ~ 30% of germline DNA from the somatic genome at each generation. How Pgm recognizes its DNA cleavage sites in chromatin is unclear and the structure-function relationships of its different domains have remained elusive. Results We provide insight into Pgm structure by determining the fold adopted by its CRD, an essential domain required for PGR. Using Nuclear Magnetic Resonance, we show that the Pgm CRD binds two Zn2+ ions and forms an unusual binuclear cross-brace zinc finger, with a circularly permutated treble-clef fold flanked by two flexible arms. The Pgm CRD structure clearly differs from that of several other PiggyBac-related transposases, among which is the well-studied PB transposase from Trichoplusia ni. Instead, the arrangement of cysteines and histidines in the primary sequence of the Pgm CRD resembles that of active transposases from piggyBac-like elements found in other species and of human PiggyBac-derived domesticated transposases. We show that, unlike the PB CRD, the Pgm CRD does not bind DNA. Instead, it interacts weakly with the N-terminus of histone H3, whatever its lysine methylation state. Conclusions The present study points to the structural diversity of the CRD among transposases from the PiggyBac family and their domesticated derivatives, and highlights the diverse interactions this domain may establish with chromatin, from sequence-specific DNA binding to contacts with histone tails. Our data suggest that the Pgm CRD fold, whose unusual arrangement of cysteines and histidines is found in all PiggyBac-related domesticated transposases from Paramecium and Tetrahymena, was already present in the ancestral active transposase that gave rise to ciliate domesticated proteins.

The atmospheric corrosion of copper exposed in Martinique (Caribbean Sea) for 1 year was reported. This island suffered the stranding of sargassum algae, which decompose and release toxic gases such as hydrogen sulfide (H2S) or ammonia (NH3). Four sites in Martinique (France) more or less impacted by sargassum algae strandings were selected. The corrosion rate was studied via mass loss determination. The morphology and properties of the corrosion products were determined using Scanning Electron Microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The samples were exposed for up to 12 months. The mass loss results after 1-year exposure were from 4.8 µm for the least impacted site to 325 µm for the site most affected by sargassum algae. This very high value proves that the presence of sargassum algae caused a significant degradation of copper. The morphological structures and properties of the corrosion products obtained at the impacted and non-impacted sites differed significantly. In the absence of sargassum algae, classical corrosion products of copper were reported such as Cu2O and Cu2Cl(OH)3. In the sites near the stranding of the sargassum algae, the CuS product is the main corrosion product obtained, but copper hydroxylsulfate is created.

Bacterial biofilms have a significant economic and health impact in many different domains. In such films, the extracellular matrix prevents the diffusion of biocides, so antibiotic treatments require a concentration 500 to 1000 times higher than that used to eliminate the same bacteria when present as planktonic stage. Early detection of biofilms is therefore essential for effective eradication. In this paper, we present the development of a real-time and label-free radiofrequency biosensor dedicated to the monitoring of bacteria and biofilm growth. Its principle relies on an open-ended coaxial probe sensitive to the variation of the electrical conductivity of the probed medium in the microwave range. As shown, between 0.3 and 1 GHz, the high sensitivity of the method (2.3 × 104 CFU/mL) highlights the biofilm growing at the early stage of its formation. To demonstrate experimentally such effects, two model bacteria, Vibrio natriegens and P. aeruginosa, are considered. The proposed method should therefore be considered as a promising technique for biofilm monitoring in batch bioreactors or flow cells experiments.

The biosynthesis of N6-threonylcarbamoylated adenosine 37 in tRNA (t6A) involves the YRDC enzyme and the KEOPS complex. Here, the authors report mutations in YRDC and the KEOPS component GON7 in Galloway-Mowat syndrome and determine the crystal structure of a GON7-containg subcomplex that suggests a role in KEOPS complex stability.

Digital documentation tools, helped by modelling, underscoring and animation techniques, allow us to recreate environments and objects that may be either partially degraded or inaccessible, with great geometric precision. This helps researchers with contextualisation, and for the public, this is an opportunity to access distant sites or sites with limited access, and to discover information that has already been interpreted.One of the first questions related to the 3D mediation of these environments is the matter of the display device. It may be a generic device, but more and more specific devices are being developed, raising many questions about the articulation between the content being displayed and the shape of the structure, way beyond the mere scenographic consideration.Of all these devices, the immersive devices offer the most interesting content. They let us experience the archaeological sites with their full context, whether they are outdoors or in enclosed spaces. Their conception immediately underlines narrative issues: chosen temporality, the processing of insufficient data, the insertion of live scenes and the treatment of atmospheres.Practice shows that, to solve those narrative issues in an immersive context, the classical visual or filmic grammar will not be sufficient. We must develop a 360° narrative grammar, a properly immersive grammar. By starting from a concrete realisation, currently in development, linked to the study of parietal arts and a corpus of references ranging from panoramas to digital tools, we will describe the constitutive parts of that 360° narrative grammar that pushes the archaeological representation beyond the descriptive visualisation and questions the relationship between the produced discourse and its visual transcription.

The nucleocapsid domain (NCd), located at the C-terminus of the HIV-1 Gag protein, is involved in numerous stages of the replication cycle, such as the packaging of the viral genome and reverse transcription. It exists under different forms through the viral life cycle, depending on the processing of Gag by the HIV-1 protease. NCd is constituted of two adjacent zinc knuckles (ZK1 and ZK2), separated by a flexible linker and flanked by disordered regions. Here, conformational equilibria between a major and two minor states were highlighted exclusively in ZK2, by using CPMG and CEST NMR experiments. These minor states appear to be temperature dependent, and their populations are highest at physiological temperature. These minor states are present both in NCp7, the mature form of NCd, and in NCp9 and NCp15, the precursor forms of NCd, with increased populations. The role of these minor states in the targeting of NCd by drugs and its binding properties is discussed.

In this study, a sensor based on the development of a planar antenna immersed in sediments dedicated to water content monitoring in this type of material is proposed and experimentally validated. It is produced by a conventional Printed Circuit Board (PCB) manufacturing process on a double-sided metalized FR4 substrate. The sensitivity of the sensor is ensured by the variation of the real part of the complex dielectric permittivity of sediments with water content at around 1 GHz. As shown, in this frequency range, electrode polarization and Maxwell−Wagner polarization effects become negligible, leading to only a bulk water polarization sensitivity. The sensor operates in the reflection mode by monitoring the variation of the resonant frequency as a function of the sediment density through the S11 reflection measurements. An experimental sensitivity of 820 MHz . g − 1 . cm 3 was achieved. Despite the simplification of data interpretation at the considered frequency, the influence of ionic species such as NaCl in sediments on the real part of the relative complex dielectric permittivity is highlighted. This demonstrates the importance of considering a second parameter such as the S11 level at low frequency or the electrical conductivity to extract the density from the frequency measurements.

Un quart de siècle est passé depuis la généralisation de l’informatique graphique dans les écoles d’architecture, une generation d’étudiants est passée et pourtant, les mêmes questions animent les equips pédagogiques sur la place à donner aux outils, à leur place et l’influence qu’ils peuvent avoir dans la conception et dans la représentation. Nous proposons ici une grille d’analyse conceptuelle et pédagogique afin de faire un état des lieux et tenter un point d’étape à ce débat.

The concept of “ambiance” has been shaped over the years by questioning the interactions between three attractors: architecture and the city, climatic and sound phenomena, uses and perception. Studied in pairs, each of these attractors refers to very different disciplinary fields; architecture and phenomena concern the physics of the city, architecture and uses interest sociology and uses and phenomena are rather turned to comfort. Studies concerning ambiances are therefore highly interdisciplinary and raise many questions: living spaces, urban renewal and heritage, urban prospective and the city as a stage. For this, many conceptual and technical tools are mobilized: digital tools for simulation and immersion, investigation, surveys and storytelling, prototyping, field action. What may be new in the field of academic studies is the awareness of artistic creation as a resource for the use of digital tools, storytelling and the representation of complexity through original means.

The recent introduction of digital tools in public lighting represents a milestone in the evolution of street lighting. Simultaneously to this innovation phase, urban lighting is currently being studied in terms of energy and environmental sobriety, to reduce its financial and ecological impact. This study presents the observations and evaluations carried out by nocturnal urban dwellers of an experimental public lighting system, set up in real conditions. The evaluations question the relevance of sensors integrated to the lighting material in real time via a series of survey managed autonomously by residents of the experimental environment.

From now preserved and presented in the museum of Nemours, the Ouche de Beauce engraved stele (Maisse, Essonne) is a representative example of the elements of architecture and the neolithic iconographic programs inventoried in Gâtinais and in western border of the massif of Fontainebleau. The study would like to expose the various recordings techniques on the monolith and on the engravings, with the aim of a surface and chronological analysis of them, inside a three-dimensional model of the support. If the so-called anthropomorph representations on a face of the stele are peculiar to the considered geographical area, an even more abstract motive registered on the opposite face is clearly under the influence of the symbolic representations from Morbihan.