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Faunal sex determination by proteomics, a valuable prospect in bioarchaeology
No full textInternational audienc
Enhanced Entanglement in the Measurement-Altered Quantum Ising Chain
No full text13 pages, 5 figures; removed residual comment from proofreadingInternational audienceUnderstanding the influence of measurements on the properties of many-body systems is a fundamental problem in quantum mechanics and for quantum technologies. This paper explores how a finite density of stochastic local measurement modifies a given state's entanglement structure. Considering various measurement protocols, we explore the typical quantum correlations of their associated projected ensembles arising from the ground state of the quantum Ising model. Using large-scale numerical simulations, we demonstrate substantial differences among inequivalent measurement protocols. Surprisingly, we observe that forced on-site measurements can enhance both bipartite and multipartite entanglement. We present a phenomenological toy model and perturbative calculations to analytically support these results. Furthermore, we extend these considerations to the non-Hermitian Ising model, naturally arising in optically monitored systems, and we show that its qualitative entanglement features are not altered by a finite density of projective measurements. Overall, these results reveal a complex phenomenology where local quantum measurements do not simply disentangle degrees of freedom, but may actually strengthen the entanglement in the system
Operando Entropy Profiling of Sodium-Ion Batteries via Optical Fiber Sensing for Thermal Management and Ageing Monitoring
No full textInternational audienceBatteries are essential for the electrification of transport and the replacement of internal combustion engines. Thermodynamics was largely established with the development of the engines, and this knowledge has been applied to batteries for years. In particular, entropy profiles are sensitive to structural changes and are useful for diagnosing and understanding battery ageing. However, entropy profiling of aged batteries is mainly limited to the potentiometric method, which makes the technique in situ and time-consuming. Herein, we rely on optical fiber calorimetry to perform operando entropy profiling of commercial sodium-ion cells. Firstly, we directly compare the entropy profile of sodium-ion Na 3 V 2 (PO 4 ) 2 F 3 /hard carbon (NVPF/HC) chemistry against those of commercialized lithium-ion chemistries, highlighting the uniqueness of NVPF/HC chemistry in battery thermal management. Operando entropy profiling of NVPF/HC chemistry further elucidates the structural degradations that take place during cycling and provide features that can be important indicators of the battery’s state of health. This work reintroduces thermodynamic analyses as a valuable tool for batteries and spotlights the new horizons offered by the convergence of battery sensing, thermodynamics, and other disciplines
Realization of an atomic quantum Hall system in four dimensions
No full textInternational audienceModern condensed matter physics relies on the concept of topology to classify matter, from quantum Hall systems to topological insulators. Engineered systems, benefiting from synthetic dimensions, can potentially give access to topological states predicted in dimensions D > 3. We report the realization of an atomic quantum Hall system evolving in four dimensions (4D), with two spatial dimensions and two synthetic ones encoded in the large spin of dysprosium atoms. We measure the nontrivial topological index of the ground band through a full characterization of the nonlinear electromagnetic response and observe the associated anisotropic hyperedge modes. We also excite nonplanar cyclotron motion, in contrast to the planar orbits in D ≤ 3. Our work may enable the investigation of strongly correlated topological liquids in 4D, generalizing fractional quantum Hall states
Dynamic local mRNA localization and translation occurs during the postnatal molecular maturation of perivascular astrocytic processes
No full textInternational audienceAbstract Astrocytes are highly ramified and send out perivascular processes (PvAPs) that entirely sheathe the brain's blood vessels. PvAPs are equipped with an enriched molecular repertoire that sustains astrocytic regulatory functions at the vascular interface. In the mouse, PvAP development starts after birth and is essentially complete by postnatal day (P) 15. Progressive molecular maturation also occurs over this period, with the acquisition of proteins enriched in PvAPs. The mechanisms controlling the development and molecular maturation of PvAPs have not been extensively characterized. We reported previously that mRNAs are distributed unequally in mature PvAPs and are locally translated. Since dynamic mRNA localization and local translation influence the cell's polarity, we hypothesized that they might sustain the postnatal maturation of PvAPs. Here, we used a combination of molecular biology and imaging approaches to demonstrate that the development of PvAPs is accompanied by the transport of mRNA and polysomal mRNA into PvAPs, the development of a rough endoplasmic reticulum (RER) network and Golgi cisternae, and local translation. By focusing on genes and proteins that are selectively or specifically expressed in astrocytes, we characterized the developmental profile of mRNAs, polysomal mRNAs and proteins in PvAPs from P5 to P60. We found that some polysomal mRNAs polarized progressively towards the PvAPs. Lastly, we found that expression and localization of mRNAs in developing PvAPs is perturbed in a mouse model of megalencephalic leukoencephalopathy with subcortical cysts. Our results indicate that dynamic mRNA localization and local translation influence the postnatal maturation of PvAPs
Motor cortex perineuronal net modulation improves motor function in a Parkinson’s disease mouse model
No full textInternational audienceAbstract The 6-OHDA mouse model recapitulates midbrain dopaminergic cell loss and associated motor deficits akin to those observed in Parkinson’s disease. Emerging evidence suggests that modulating interneurons in the primary motor cortex could offer a means to mitigate symptoms. In the cortex, perineuronal nets (PNNs), a specialized extracellular matrix structure generally present around fast-spiking parvalbumin interneurons, can modulate neural activity and circuit plasticity. We found that removing PNNs through unilateral or bilateral ChABC injection in the motor cortex temporarily altered motor behavior. Surprisingly, bilateral reduced motor cortex PNNs are observed two weeks after unilateral 6-OHDA midbrain lesions, whereas five weeks after lesion, PNNs return to control levels. Subsequent bilateral ChABC injections significantly improved motor function in 6-OHDA animals only when associated with motor stimulation involving enriched housing and daily motor training. Thus, PNN modulation in the motor cortex of a Parkinson’s disease model enables local circuits to adapt to the loss of dopaminergic inputs, resulting in improved motor behavior
La juridiction du podestat génois de Péra au prisme du registre du patriarcat de Constantinople
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Shell Beads and Pigments Associated with Châtelperronian Artifacts atLa Roche-à-Pierrot, Saint-Césaire, France
No full textInternational audienceLa Roche-à-Pierrot is well-known for the 1979 discovery of a partial Neanderthal skeleton from what was described at the time as a Châtelperronian level (EJOP sup). Since then, the site has played a key role in discussions concerning the Middle-to-Upper Paleolithic transition in western Europe. Excavated by F. Lévêque over a period of 11 years, the collapsed rock-shelter of La Roche-à-Pierrot has produced a near complete stratigraphic sequence preserving late Mousterian to recent Aurignacian occupations (Lévêque et al. 1993). A recent reassessment of Lévêque’s lithic assemblage highlighted both incoherencies in material culture associations and stratigraphy (Gravina et al. 2018). Since 2013, renewed fieldwork and geoarchaeological work have provided new important information concern-ing site formation processes, allowing spatial inconsistencies to be tested and the site’s chronology and lithostratigraphic sequence to be reassessed (Couillet et al., 2022; Todisco et al. 2023). Here we present a concentration of Châtelperronian lithic artifacts associated with personal ornaments and red pigments from stratigraphic unit 18-19 (US18/19), correlatable with Léveque’s EJOP sup. The per-sonal ornament assemblage is dominated by marine gastropods of the genus Littorina, two thirds of which present clear anthropogenic perforations. While Middle Paleolithic artifacts are present in US18/19, a statistically supported, multi-proxy spatial and taphonomic analysis demonstrates the shell beads and pigments to be clearly associated with its Châtelperronian component. This is the first time that shell beads have been associated with the Châtelperronian. While anthropogenically perforated shells are unknown from Middle Paleolithic contexts, diverse perforated marine gastropods have been recovered from sites contemporaneous with the Châtelperronian in southeastern Europe and around the Mediterranean. This hitherto undocumented combination of a western European early Upper Paleolithic industry and shell beads provides new evidence for discussing cultural and/or biological connections between the various human groups present in Eurasia during this important period of human evolution
Social Skills and the Individual Wage Growth of Less Educated Workers
No full textThis study employs matched employee-employer data from the UK to highlight the importance of social skills, in particular workers’ ability to work well in a team and communicate effectively with co-workers, as a driver of wage growth for workers with lower formal education. Our findings indicate that in tasks emphasizing social skills, such workers not only enjoy greater wage progression with tenure but also accrue higher returns in environments with a higher concentration of more educated colleagues. Additionally, workers’ exit occur sooner from jobs where social skills are more important. We rationalize these dynamics through a model that assesses social skills based on their complementarity with a firm’s assets and where a worker’s social skills, initially opaque to both the employee and employer, become increasingly apparent ove