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Valvometry techniques used to monitor bivalve gaping activity have elucidated numerous relationships with environmental fluctuations, along with biological rhythms ranging from sub-daily to seasonal. Thus, a precise understanding of the natural activity of bivalves (i.e., not exposed to stressful environmental variations) is necessary as a baseline for detecting abnormal behaviors (deviations). This knowledge is also needed to reliably interpret observations of bivalve gaping behavior and associated biological processes (e.g., respiration, nutrition) acquired over time-limited periods. With this in mind, we investigated the natural daily gaping activity of the great scallop (Pecten maximus) by continuously monitoring 35 individuals in several individual tanks and in situ (Bay of Saint-Brieuc, Brittany, France) using fully autonomous Hall effect sensors. Our results revealed a circadian cycle (τ = 24.0h) in scallop gaping activity. Despite significant inter-individual variability in mean opening and cycle amplitude, almost all individuals (87.5%) exhibited nocturnal activity, with valves more open at night than during the day. A shift in light regime in the tanks triggered an instantaneous change in opening pattern, indicating that light levels strongly determine scallop activity. Based on the opening status of scallops, we also identified several gaping behaviors deviating from the regular daily pattern (lack of rhythmicity, high daytime opening), potentially reflecting physiological weakness. While further long-term studies are required to fully understand the natural activity of scallops, these findings pave the way for studies focused on the scallop response to external factors and introduce further research into the detection of abnormal behaviors. Coupling observations of diel valve gaping cycles with other daily variations in organismal and environmental parameters could help explain mechanisms driving the growth patterns of scallops observed in their shell striations. From a technical perspective, our field-based monitoring demonstrates the suitability of autonomous valvometry sensors for studying mobile subtidal bivalve activity in remote offshore environments., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Retailleau et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

While several studies have investigated the potential impact of nanoplastics, proof of their occurrence in our global environment has not yet been demonstrated. In the present work, by developing an innovative analytical strategy, the presence of nanoplastics in soil was identified for the first time. Our results demonstrate the presence of nanoplastics with a size ranging from 20 to 150 nm and covering three of the most common plastic families: polyethylene, polystyrene and polyvinyl chloride. Given the amount of organic matter in the soil matrix, the discrimination and identification of large nanoplastic aggregates are challenging. However, we provided an innovative methodology to circumvent the organic matter impact on nanoplastic detection by coupling size fractionation to molecular analysis of plastics. While photodegradation has been considered the principal formation pathway of nanoplastics in the environment, this study provides evidence, for the first time, that plastic degradation and nanoplastic production can, however, occur in the soil matrix. Moreover, by providing an innovative and simple extraction/analysis method, this study paves the way to further studies, notably regarding nanoplastic environmental fate and impacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

We described nosocomially clustered cases of measles secondary to a nonvaccinated index case occurring in a teenage psychiatric unit despite optimum vaccine coverage. Surveillance of this fully vaccinated closed cohort showed a 7% attack rate. Vaccination limited the risk of complicated measles and the onset of a large outbreak.

The nanoscale size of plastic debris makes them potential efficient vectors of many pollutants and more especially of metals. In order to evaluate this ability, nanoplastics were produced from microplastics collected on a beach exposed to the North Atlantic Gyre. The nanoplastics were characterized using multi-dimensional methods: asymmetrical flow field flow fractionation and dynamic light scattering coupled to several detectors. Lead (II) adsorption kinetics, isotherm and pH-edge were then carried out. The sorption reached a steady state after around 200 min. The maximum sorption capacity varied between 97% and 78.5% for both tested Pb concentrations. Lead (II) adsorption kinetics is controlled by chemical reactions with the nanoplastics surface and to a lesser extent by intraparticle diffusion. Adsorption isotherm modeling using Freundlich model demonstrated that NPG are strong adsorbents equivalent to hydrous ferric oxides such as ferrihydrite (log K ads freundlich =8.36 against 11.76 for NPG and ferrihydrite, respectively). The adsorption is dependent upon pH, in response to the Pb(II) adsorption by the oxygenated binding sites developed on account of the surface UV oxidation under environmental conditions. They could be able to compete with Fe or humic colloids for Pb binding regards to their amount and specific areas. Nanoplastics could therefore be efficient vectors of Pb and probably of many other metals as well in the environment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Bacillus thuringiensis subsp. israelensis is a bioinsecticide increasingly used worldwide for mosquito control. Despite its apparent low level of persistence in the field due to the rapid loss of its insecticidal activity, an increasing number of studies suggested that the recycling of B. thuringiensis subsp. israelensis can occur under specific, unknown conditions. Decaying leaf litters sampled in mosquito breeding sites in the French Rhône-Alpes region several months after a treatment were shown to exhibit a high level of larval toxicity and contained large amounts of spores. In the present article, we show that the high concentration of toxins found in these litters is consistent with spore recycling in the field, which gave rise to the production of new crystal toxins. Furthermore, in these toxic leaf litter samples, Cry4Aa and Cry4Ba toxins became the major toxins instead of Cyt1Aa in the commercial mixture. In a microcosm experiment performed in the laboratory, we also demonstrated that the toxins, when added in their crystal form to nontoxic leaf litter, exhibited patterns of differential persistence consistent with the proportions of toxins observed in the field-collected toxic leaf litter samples (Cry4 > Cry11 > Cyt). These results give strong evidence that B. thuringiensis subsp. israelensis recycled in specific breeding sites containing leaf litters, and one would be justified in asking whether mosquitoes can become resistant when exposed to field-persistent B. thuringiensis subsp. israelensis for several generations.

Ewing sarcoma, a pediatric tumor characterized by EWSR1-ETS fusions, is predominantly observed in populations of European ancestry. We performed a genome-wide association study (GWAS) of 401 French individuals with Ewing sarcoma, 684 unaffected French individuals and 3,668 unaffected individuals of European descent and living in the United States. We identified candidate risk loci at 1p36.22, 10q21 and 15q15. We replicated these loci in two independent sets of cases and controls. Joint analysis identified associations with rs9430161 (P = 1.4 × 10(-20); odds ratio (OR) = 2.2) located 25 kb upstream of TARDBP, rs224278 (P = 4.0 × 10(-17); OR = 1.7) located 5 kb upstream of EGR2 and, to a lesser extent, rs4924410 at 15q15 (P = 6.6 × 10(-9); OR = 1.5). The major risk haplotypes were less prevalent in Africans, suggesting that these loci could contribute to geographical differences in Ewing sarcoma incidence. TARDBP shares structural similarities with EWSR1 and FUS, which encode RNA binding proteins, and EGR2 is a target gene of EWSR1-ETS. Variants at these loci were associated with expression levels of TARDBP, ADO (encoding cysteamine dioxygenase) and EGR2.