Atomic Energy and Alternative Energies Commission

Single particle mass analysis methods allow the measurement and characterization of individual nanoparticles, viral particles, as well as biomolecules like protein aggregates and complexes. Several key benefits are associated with the ability to analyze individual particles rather than bulk samples, such as high sensitivity and low detection limits, and virtually unlimited dynamic range, as this figure of merit strictly depends on analysis time. However, data processing and interpretation of single particle data can be complex, often requiring advanced algorithms and machine learning approaches. In addition, particle ionization, transfer, and detection efficiency can be limiting factors for certain types of analytes. Ongoing developments in the field aim to address these challenges and expand the capabilities of single particle mass analysis techniques. Charge detection mass spectrometry is a single particle version of mass spectrometry in which the charge (z) is determine independently from m/z. Nano‐electromechanical resonator mass analysis relies on changes in a nanoscale device's resonance frequency upon deposition of a particle to directly derive its inertial mass. Mass photometry uses interferometric video‐microscopy to derive particle mass from the intensity of the scattered light. A common feature of these approaches is the acquisition of single particle data, which can be filtered and concatenated in the form of a particle mass distribution. In the present article, dedicated to our honored colleague Richard Cole, we cover the latest technological advances and applications of these single particle mass analysis approaches.

Microplastics provide a persistent substrate that can facilitate microbial transport across ecosystems. Since most marine plastic debris originates from land and reaches the ocean through rivers, the potential dispersal of freshwater bacteria into the sea represents a significant concern. To address this question, we explored the plastisphere on microplastic debris (MPs) and on pristine microplastics (pMPs) as well as the bacteria living in surrounding waters, along the river-sea continuum in nine major European rivers sampled during the 7 months of the Tara Microplastics mission. In both marine and riverine waters, we found a clear niche partitioning among MPs and pMPs plastispheres when compared to the bacteria living in the surrounding waters. Across this large dataset, we found that bacterial community structure varied along the river salinity gradient, with plastisphere communities exhibiting almost complete segregation between freshwater and marine ecosystems. We also described for the first time a virulent human pathogenic bacterium (Shewanella putrefaciens), capable of infecting human intestinal epithelial cells, detected exclusively on MPs in riverine environments. Our findings indicate that salinity is the main driver of plastisphere communities along the river-to-sea continuum, helping to mitigate the risk of pathogens transfer between freshwater and marine systems. Graphical Abstract

This article describes the synthesis of a difluorinated CinNapht derivative in the 4′ and 5′ positions allowing the easy access to two new families of fluorophores by late‐stage functionalization using SNAr. The first one comprises derivatives incorporating hindered aromatic amines in the 4′ and 5′ positions, which show red‐emission in apolar solvents. The second one is obtained through the use of dinucleophiles. Among them, Tetrahydroquinoxaline (THQ) and tetrahydrobenzodiazepine (THB) compounds show strongly redshifted emission. The photophysical properties of all the fluorophores in these two families are studied and rationalized by DFT and TDDFT calculations. The most promising compounds have been used to image living cells by confocal microscopy.

A model of imbibition dynamics in a channel of flattened triangular cross-section is presented, taking into account the liquid film flow in the corners of the channel. The quasi-analytical solutions are derived on the basis of a lubrication approximation. The analysis encompasses two imbibition scenarios corresponding to a constant flow rate or constant pressure imposed in the wetting fluid at the inlet of the channel. In the former case, the process starts with a liquid film flow regime in the corners that is followed by a bulk and corner film flow regime characterised by a triple point advancing (far) ahead of the bulk meniscus after its entrance in the channel. In the latter case, the occurrence of the bulk and corner film flow regime is conditioned by an imposed pressure yielding a capillary pressure at the inlet smaller than a threshold capillary pressure. Above this threshold, the liquid film regime remains. For both imbibition scenarios under concern, important features are highlighted, including (i) the time scalings of the dynamics of both the triple point and apex of the bulk meniscus (when it exists), (ii) the contrast in the positions of these two points showing that the classical Washburn approach, which neglects the effect of the corner films, overpredicts the dynamics of the bulk meniscus. The important consequence is an early wetting fluid breakthrough at the channel outlet much before the bulk meniscus arrival. Comparisons with experimental data available in the literature are provided, validating the approach proposed in this work.

Epithelial–mesenchymal transition (EMT) involves profound changes in cell morphology, driven by transcriptional and epigenetic reprogramming. However, evidence suggests that translation and ribosome composition also play key roles in establishing pathophysiological phenotypes. Using genome-wide analyses, we reported significant rearrangement of the translational landscape and machinery during EMT. Specifically, a cell line overexpressing the EMT transcription factor ZEB1 displayed alterations in translational reprogramming and fidelity. Furthermore, using riboproteomics, we unveiled an increased level of the ribosomal protein RPL36A in mesenchymal ribosomes, indicating precise tuning of ribosome composition. Remarkably, RPL36A overexpression alone was sufficient to trigger the acquisition of mesenchymal features, including a switch in the molecular pattern, cell morphology, and behavior, demonstrating its pivotal role in EMT. These findings underline the importance of translational reprogramming and fine-tuning of ribosome composition in EMT.

Correction for ‘Perylene-derivative singlet exciton fission in water solution’ by Chloe Magne et al., Chem. Sci., 2024, 15, 17831–17842, https://doi.org/10.1039/D4SC04732J.

Several Old World and New World Mammarenavirus are responsible for hemorrhagic fever in humans. These enveloped viruses have a bi-segmented ambisense RNA genome that encodes four proteins. All Mammarenavirus identified to date share a common dependency on myristoylation: the addition of the C14 myristic acid on the N-terminal G2 residue on two of their proteins. The myristoylation of the Z matrix protein is required for viral particle budding, while the myristoylation of the signal peptide to the envelope glycoproteins is important for the entry mechanism. Using Mopeia virus as a model, we characterized the interaction of the Z matrix protein with the N-Myristoyltransferases (NMT) 1 and 2, the two enzymes responsible for myristoylation in mammals. While both enzymes were capable to interact with Z, we showed that only NMT1 was important for the production of viral progeny, the endogenous expression of NMT2 being insufficient to make up for NMT1 in its absence. Using the high affinity inhibitors of NMTs, IMP1088 and DDD85646, we demonstrated a strong, dose dependent and specific inhibition at the nanomolar range for all Mammarenavirus tested, including the highly pathogenic Lassa, Machupo, Junin and Lujo viruses. Mechanistically, IMP1088 and DDD85646 blocked the interaction between Z and both NMTs, preventing myristoylation and further viral particle formation, egress and spread. Unexpectedly, we found that the matrix protein devoid of myristate, despite being fully translated, did not accumulate as the other viral proteins in infected cells but was instead degraded in a proteasome- and autophagy-independent manner. These molecules represent a new broad-spectrum class of inhibitors against Mammarenavirus .

A safe and efficient lithium‐ion battery requires including an additive in the electrolyte. Among the additives used, vinylene carbonate (VC) is particularly interesting, because it leads to the formation of a stable and protective solid electrolyte interphase (SEI) on the negative electrode. However, the reduction behavior of VC, resulting in polymer formation, is complex, and many questions remain as to the corresponding reaction mechanisms. In particular, in conventional battery studies, it is not possible to observe the transient species formed during reduction. Using picosecond pulsed radiolysis coupled with theoretical chemistry calculations, we showed that, once formed, the anion radical VC·− can undergo ring opening in a few nanoseconds or form (VC)2·−. Within 100 ns, each of these anions then leads to the formation of (VC)(C3H2O3·−). This latter species starts oligomerizing. Eventually, a polymer is formed. Although it mainly consists of poly(VC) units, other chemical functions, such as alkyl groups, are also present, which highlights the role played by water, even in trace amounts. Lastly, we propose a scheme of the reaction mechanisms involved in VC reduction, leading to its polymerization. Clearly, the polymer formed from VC at the SEI of lithium‐ion batteries has a complex structure.

Measuring deeply virtual Compton scattering (DVCS) on the neutron is one of the necessary steps to understand the structure of the nucleon in terms of generalized parton distributions (GPDs). Neutron targets play a complementary role to transversely polarized proton targets in the determination of the GPD E . This poorly known and poorly constrained GPD is essential to obtain the contribution of the quarks’ angular momentum to the spin of the nucleon. DVCS on the neutron was measured for the first time selecting the exclusive final state by detecting the neutron, using the Jefferson Lab longitudinally polarized electron beam, with energies up to 10.6 GeV, and the CLAS12 detector. The extracted beam-spin asymmetries, combined with DVCS observables measured on the proton, allow a clean quark-flavor separation of the imaginary parts of the Compton form factors H and E . Published by the American Physical Society 2024

Fast, accurate, and affordable bacterial identification methods are paramount for the timely treatment of infections, especially in resource-limited settings (RLS). However, today, only 1.3% of the sub-Saharan African diagnostic laboratories are performing clinical bacteriology. To improve this, diagnostic tools for RLS should prioritize simplicity, affordability, and ease of maintenance, as opposed to the costly equipment utilized for bacterial identification in high-income countries, such as matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). In this work, we present a new high-throughput approach based on a simple wide-field (864 mm²) lensless imaging system allowing for the acquisition of a large portion of a Petri dish coupled with a supervised deep learning algorithm for identification at the bacterial colony scale. This wide-field imaging system is particularly well suited to RLS since it includes neither moving mechanical parts nor optics. We validated this approach through the acquisition and the subsequent analysis of a dataset comprising 252 clinical isolates from five species, encompassing some of the most prevalent pathogens. The resulting optical morphotypes exhibited intra- and interspecies variability, a scenario considerably more akin to real-world clinical practice than the one achievable by solely concentrating on reference strains. Despite this variability, high identification performance was achieved with a correct species identification rate of 91.7%. These results open up some new prospects for identification in RLS. We released both the acquired dataset and the trained identification algorithm in publicly available repositories.

Uranyl and nickel(II) nitrates have been reacted with cis‐1,2‐cyclohexanedicarboxylic (H2chdc) and isonicotinic (Hint) acids under solvo‐hydrothermal conditions, giving the heterometallic, mixed‐ligand complex [(UO2)2Ni(chdc)2(int)2]⋅CH3CN (1). The uranyl cation is bound to carboxylate groups of both ligands while NiII is attached to two carboxylate and two nitrogen donors, with two strong additional interactions with uranyl oxo groups giving a nearly regular octahedral environment. The short Ni–O(oxo) bond length of 2.114(3) Å amounts to 67% of the sum of van der Waals radii. The trimetallic (UO2)2Ni6+ clusters thus formed are assembled by chdc2– ligands into linear chains which are further bridged by int– links to give a triperiodic framework with the dia topology, in which small channels encompass two rows of acetonitrile solvent molecules. Complex 1 does not display uranyl luminescence under excitation in the solid state.

Original covalent probes with an N‐acyl‐N‐alkyl sulfonamide cleavable linker were developed to target a broad set of human Matrix Metalloproteases (MMPs). The electrophilicity of this cleavable linker was modulated to improve the selectivity of the probes as well as reduce their unspecific reactivity in complex biological matrices. We first demonstrated that targeting the S3 subsite of MMPs enables access to broad‐spectrum affinity‐based probes that exclusively react with the active version of these proteases. The probes were further assessed in proteomes of varying complexity, where human MMP‐13 was artificially introduced at known concentration and the resulting labeled MMP was imaged by in‐gel fluorescence imaging. We showed that the less reactive probe was still able to covalently modify MMP‐13 while exhibiting reduced off‐target unspecific reactivity. This study clearly demonstrated the importance of finely controlling the reactivity of the NASA warhead to improve the selectivity of covalent probes in complex biological systems.

The integration of Renewable Energy Sources (RES) into the power grid is limited by two inherent characteristics: intermittency and low inertia. These characteristics negatively impact system stability, particularly in terms of frequency stability. If the penetration of RES in a power system exceeds a certain threshold, the frequency stability of the system is compromised. This paper proposes and validates the effectiveness of combining Fault Ride Through (FRT) with Battery Energy Storage Systems (BESS) to address these challenges in various scenarios. Subsequently, the research employs the Particle Swarm Optimization (PSO) algorithm to determine the optimal parameters of both the BESS and Power System Stabilizer (PSS) for all the Synchronous Generators in a microgrid, achieving improved frequency stability. The results reveal the combined application of these two methods proves highly effective in enhancing system stability, even when RES account for 100% of the system's generation capacity.

A semi‐heterogeneous photocatalytic system was assembled through encapsulation of a lipophilic porphyrin in stabilized polydiacetylene micelles. The colloidal nanohybrid catalyst was valorized in the aerobic photo‐oxidation of sulfides to the corresponding sulfoxides. Micelles behaved as nanoreactors by creating a favorable environment for the photo‐activation of oxygen nearby thioethers and subsequent sulfoxidation. The process operates selectively under visible light and air atmosphere, with low catalytic loading and in water as the only solvent.

Hydroboranes are versatile reagents in synthetic chemistry, but their synthesis relies on energy‐intensive processes. Herein, we report a new method for the preparation of hydroboranes from hydrogen and the corresponding haloboranes. Triethylamine (NEt3) form with dialkylchloroboranes a Frustrated Lewis Pair (FLP) able to split H2 and afford the desired hydroborane with ammonium salts. Unreactive haloboranes were unlocked using a catalytic amount of Cy2BCl, enabling the synthesis of commonly used hydroboranes such as pinacolborane or catecholborane. The mechanisms of these reactions have been examined by DFT studies, highlighting the importance of the base selection. Finally, the system‘s robustness has been evaluated in one‐pot B−Cl hydrogenolysis/hydroboration reactions of C=C unsaturated bonds.