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Efficient Quantum Circuits for Non-Unitary and Unitary Diagonal Operators with Space-Time-Accuracy trade-offs
No full textInternational audienceUnitary and non-unitary diagonal operators are fundamental building blocks in quantum algorithms with applications in the resolution of partial differential equations, Hamiltonian simulations, the loading of classical data on quantum computers (quantum state preparation) and many others. In this paper, we introduce a general approach to implement unitary and non-unitary diagonal operators with efficient-adjustable-depth quantum circuits. The depth, i.e. the number of layers of quantum gates of the quantum circuit, is reducible with respect either to the width, i.e. the number of ancilla qubits, or to the accuracy between the implemented operator and the target one. While exact methods have an optimal exponential scaling either in terms of size, i.e. the total number of primitive quantum gates, or width, approximate methods prove to be efficient for the class of diagonal operators depending on smooth, at least differentiable, functions. Our approach is general enough to allow any method for diagonal operators to become adjustable-depth or approximate, decreasing the depth of the circuit by increasing its width or its approximation level. This feature offers flexibility and can match with the hardware limitations in coherence time or cumulative gate error. We illustrate these methods by performing quantum state preparation and non-unitary-real-space simulation of the diffusion equation: an initial Gaussian function is prepared on a set of qubits before being evolved through the non-unitary evolution operator of the diffusion process
Tunneling of quantum geometries in spinfoams
No full textInternational audienceQuantum gravitational tunneling effects are expected to give rise to a number of interesting observable phenomena, including, in particular, the evolution of black holes at the end of their existence or the emergence of the early universe from a quantum phase. Covariant Loop Quantum Gravity provides a framework to study these phenomena, yet a precise identification of tunneling processes is still not known. Motivated by this question, we consider a related, simpler case, that of Ponzano-Regge amplitudes: we find a surprising and detailed analogy of a class of simple transition amplitudes with tunneling processes in non-relativistic quantum mechanics
French Society for Biological Psychiatry and Neuropsychopharmacology (AFPBN) guidelines for the management of patients with partially responsive depression and treatment-resistant depression: Update 2024
No full textInternational audienceIntroduction: The purpose of this update is to add newly approved nomenclatures and treatments as well as treatments yet to be approved in major depressive disorder, thus expanding the discussions on the integration of resistance factors into the clinical approach.Methods: Unlike the first consensus guidelines based on the RAND/UCLA Appropriateness Method, the French Association for Biological Psychiatry and Neuropsychopharmacology (AFPBN) developed an update of these guidelines for the management of partially responsive depression (PRD) and treatment-resistant depression (TRD). The expert guidelines combine scientific evidence and expert clinicians' opinions to produce recommendations for PRD and TRD.Results: The recommendations addressed three areas judged as essential for updating the previous 2019 AFPBN guidelines for the management of patients with TRD: (1) the identification of risk factors associated with TRD, (2) the therapeutic management of patients with PRD and TRD, and (3) the indications, the modalities of use and the monitoring of recent glutamate receptor modulating agents (esketamine and ketamine).Conclusion: These consensus-based guidelines make it possible to build bridges between the available empirical literature and clinical practice, with a highlight on the 'real world' of the clinical practice, supported by a pragmatic approach centred on the experience of specialised prescribers in TRD
Optimal portfolio with vector expected utility
No full textACL-2International audienceWe study the optimal portfolio selected by an investor who conforms to Siniscalchi (2009)'s Vector Expected Utility's (VEU) axioms and who is ambiguity averse. To this end, we derive a mean-variance preference generalised to ambiguity from the second-order Taylor-Young expansion of the VEU certainty equivalent. We apply this Mean-Variance Variability preference to the static two-assets portfolio problem and deduce asset allocation results which extend the mean-variance analysis to ambiguity in the VEU framework. Our criterion has attractive features: it is axiomatically well-founded and analytically tractable, it is therefore well suited for applications to asset pricing as proved by a novel analysis of the home-bias puzzle with two ambiguous assets
Constraining the TeV gamma-ray emission of SN 2024bch, a possible type IIn-L from a red supergiant progenitor - Multiwavelength observations and analysis of the progenitor
No full textInternational audienceWe present very high-energy optical photometry and spectroscopic observations of SN 2024bch in the nearby galaxy NGC 3206 (∼20 Mpc). We used gamma-ray observations performed with the first Large-Sized Telescope (LST-1) of the Cherenkov Telescope Array Observatory (CTAO) and optical observations with the Liverpool Telescope (LT) combined with data from public repositories to evaluate the general properties of the event and the progenitor star. No significant emission above the LST-1 energy threshold for this observation (∼100 GeV) was detected in the direction of SN 2024bch, and we computed an integral upper limit on the photon flux of Fγ(> 100 GeV)≤3.61 × 10−12 cm−2 s−1 based on six nonconsecutive nights of observations with the LST-1, between 16 and 38 days after the explosion. Employing a general model for the gamma-ray flux emission, we found an upper limit on the mass-loss-rate to wind-velocity ratio of Ṁ/uw ≤ 10−4 M⊙/ yr s/km, although gamma-gamma absorption could potentially have skewed this estimation, effectively weakening our constraint. From spectro-photometric observations we found progenitor parameters of Mpr = 11 – 20 M⊙ and Rpr = 531 ± 125 R⊙. Finally, using archival images from the Hubble Space Telescope, we constrained the luminosity of the progenitor star to log (Lpr/L⊙) ≤ 4.82 and its effective temperature to Tpr ≤ 4000 K. Our results suggest that SN 2024bch is a type IIn-L supernova that originated from a progenitor star consistent with a red supergiant. We show how the correct estimation of the mass-loss history of a supernova will play a major role in future multiwavelength observations.Key words: supernovae: general / supernovae: individual: SN 2024bch / gamma rays: genera
De l’invisibilité à la représentation. Difficultés, enjeux et perspectives d’une expérience inédite impliquant les non-citoyens, conçue et réalisée par le « laboratoire romain »
No full textInternational audienceThis study aims to find out the dynamics operating in invisibilisation and visibilisation processes concerning a given category of persons, such as migrants in contemporary societies. Both invisibilisation processes and visibilisation processes may have contradictory effects. Both may take place in different spaces. Furthermore, they may circulate across different spaces. Invisibility and visibility can thus be social, statistical, geographical, mediatic, political, juridical, etc. Invisibility and visibility may be negatively experienced by migrants, in different spaces. By analysing an “extraordinary” initiative designed by the “Roman laboratory” to address the problem of invisibility or visibility suffered by migrants, we show 1) how migrants can make themselves visible as they would like to be, through actions making them representable by participation, 2) how they can participate in operations producing visibility as fundamental actors of their representation. Several points emerge from our analysis. In particular, this study tends to demonstrate that visibilisation and representation are strongly linked to each other. This study shows how it is possible to contribute to producing your visibility by participating in representation processes fostering your visibility. These processes require proper means and resources, in order that they can take place correctly. Moreover, this study highlights the importance of effective communication and involvement, appropriate to circumstances, so as to achieve this aim.Notre étude vise à éclairer les dynamiques à l’œuvre dans les processus d’invisibilisation et de visibilisation d’une catégorie donnée de personnes, en l’occurrence les migrants au sein des sociétés contemporaines. Tant les processus d’invisibilisation que les processus de visibilisation peuvent avoir des effets contradictoires. Ils peuvent se produire dans des espaces différents et circuler d’un espace à l’autre. L’invisibilité et la visibilité peuvent ainsi être sociales, statistiques, géographiques, médiatiques, politiques, juridiques, etc. L’invisibilité et la visibilité peuvent être vécues négativement par les migrants, dans des espaces différents. En analysant une initiative « extra-ordinaire », mise en œuvre par le « laboratoire romain », visant à résoudre le problème de l’invisibilité ou de la visibilité subies par les migrants, nous montrons 1) comment les migrants peuvent arriver à se rendre visibles de leur gré par des démarches qui les rendent représentables à travers leur participation, 2) comment ils peuvent participer à une opération de production de visibilité en tant qu’acteurs primordiaux de leur représentation. Plusieurs points émergent de notre analyse. En particulier, notre étude tend à démontrer que visibilisation et représentation sont étroitement liées. Elle montre comment on peut concourir à la production de sa visibilité par la participation aux processus de représentation qui contribuent à sa visibilisation. Ceux-ci nécessitent ressources et moyens adéquats pour qu’ils puissent se dérouler convenablement. De plus, notre étude fait valoir l’importance d’une communication et d’une mobilisation efficaces et appropriées aux circonstances pour parvenir à cet objectif
Tableaux for Epistemic Gödel Logic
No full textInternational audienceWe propose a multi-agent epistemic logic capturing reasoning with degrees of plausibility that agents can assign to a given statement with 1 interpreted as 'entirely plausible for the agent' and 0 as 'completely implausible' (i.e., the agent knows that the statement is false). We formalise such reasoning in an expansion of Gödel fuzzy logic with an involutive negation and multiple S5-like modalities. As already Gödel single-modal logics are known to lack the finite model property w.r.t. their standard [0, 1]-valued Kripke semantics, we provide an alternative semantics that allows for the finite model property. For this semantics, we construct a strongly terminating tableaux calculus that allows us to produce finite counter-models of non-valid formulas. We then use the tableaux to show that the validity problem in our logic is PSpace-complete when there are two or more agents, and coNP-complete for the single-agent case.</div
The metabolic profile of circulating plasmacytoid dendritic cells from patients with systemic sclerosis
No full textInternational audienceObjective: Plasmacytoid dendritic cells (pDCs) play a key role in the pathophysiology of systemic sclerosis (SSc). However, despite the recognised importance of metabolic reprogramming for immune cell function, the metabolic profile of pDCs in SSc remains to be elucidated. Thus, our study aimed to investigate the role of pDC metabolism in SSc.Methods: Peripheral blood mononuclear cells (PBMCs) were isolated from the blood of healthy donors and SSc patients. SCENITH, a single-cell flow cytometry-based method, was applied to infer the metabolic profile of circulating pDCs from patients with SSc. pDCs (CD304 + Lin -) at steady-state or stimulated with CpG A were analysed. Toll-like receptor (TLR)9 activation was confirmed by S6 phosphorylation.Results: Circulating pDCs from 10 healthy donors and from 14 SSc patients were analysed. pDCs from anti-centromere antibody-positive (ACA + ) patients displayed higher mitochondrial dependence and lower glycolytic capacity than those from antitopoisomerase I antibody-positive (ATA + ) patients. Furthermore, cells from both ACA + patients and limited cutaneous SSc (lcSSc) patients showed a stronger response towards TLR9 activation than cells from ATA + , anti-RNA polymerase III antibody-positive (ARA + ) or diffuse cutaneous SSc (dcSSc) patients.Conclusions: Our results suggest that pDCs from ACA + patients rely more on oxidative phosphorylation (OXPHOS) and are more responsive to external stimuli, indicating that pDCs from ARA + patients may be more activated or exhausted. These findings point for the possible contribution of the metabolic profile of pDCs for SSc clinical course, unveiling new possible targets for therapeutic approaches in SSc.</div
Limits of Duty of Care in Global Supply Chains: A Comparative Analysis
No full textInternational audienceFor four decades, global supply chains have occupied a central position in academic and political debates, driven by the growing imperative to reconcile economic performance with corporate social responsibility. Within this context, soft law has emerged as the favored mechanism for transnational regulation, functioning both as a catalyst for normative innovation and as a strategic means to circumvent more stringent constraints on flow management. A comparative analysis of France and the United States reveals two distinct paradigms: a formalized, legalistic, and preventive French framework centered on the duty of vigilance-a uniquely French statutory obligation-and a more coercive U.S. framework that leverages customs sanctions alongside geopolitical objectives, albeit applied selectively. The article's originality stems from its critical integration of legal and management perspectives, transcending the simplistic dichotomy between restrictive regulation and self-regulation. Employing comparative social science methodologies, it opens significant research avenues into the prerequisites for inclusive transnational governance, emphasizing the mobilization of diverse stakeholders and hybrid control mechanisms to transform the broader principle of duty of care into an instrument of enhanced logistical justice
