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An Attack on ML-DSA Using an Implicit Hint
No full textInternational audienceThe security of ML-DSA, like most signature schemes, is partially based on the fact that the nonce used to generate the signature is unknown to any attacker. In this work, we exhibit a lattice-based attack that is possible if the nonces share implicit or explicit information. From a collection of signatures whose nonces share certain coefficients, it is indeed possible to build a collection of non full-rank lattices. Intersecting them, we show how to create a low-rank lattice that contains one of the polynomials of the secret key, which in turn can be recovered using lattice reduction techniques.There are several interpretations of this result: firstly, it can be seen as a generalization of a fault-based attack on BLISS presented at SAC’16 by Thomas Espitau et al.. Alternatively, it can be understood as a side-channel attack on ML-DSA, in the case where an attacker is able to recover only one of the coefficients of the nonce used during the generation of the signature. For ML-DSA-II, we show that signatures and few hours of computation are sufficient to recover the secret key on a desktop computer. Lastly, our result shows that simple countermeasures, such as permuting the generation of the nonce coefficients, are not sufficient
Spaces of triangularizable matrices (II): Finite fields with odd characteristic
No full textInternational audienceLet be a field with characteristic other than 2. Denote by the greatest possible dimension for a vector space of n-by-n matrices over in which every element is triangularizable over .It was recently proved that if and only if is not quadratically closed. The structure of the spaces of maximal dimension was also elucidated provided is infinite and not quadratically closed. In this sequel, we extend this result to finite fields. More specifically, we prove that if is finite, then the space of all upper-triangular n-by-n matrices is, up to conjugation, the sole vector space of n-by-n matrices that has dimension and consists only of triangularizable matrices
Relevance of Clinical High-Risk of Psychotic Transition Conceptto Avoid Misdiagnosis Risk in an Unaccompanied Minor Refugeewith Complex Trauma: A Case Report
No full textInternational audienceIntroduction: Unaccompanied refugee minors face a heightened risk of mental health disorders due to cumulative traumatic exposures and sociocultural displacement. Psychotic-like symptoms are common and frequently misdiagnosed as primary psychotic disorders, often overlooking trauma-related or culturally-influenced presentations. Case Presentation: We report the case of “Moussa”, a 15-year-old URM from Cameroon, who presented with transient psychotic symptoms during an acute stress episode. Following the CAARMS assessment, he was initially diagnosed with a Clinical High-Risk for psychosis state (CHRp), then later labeled as schizophreniform by another provider. However, his rapid remission and trauma history led to a revised diagnosis of complex PTSD. Conclusion: This case underscores the risks of early psychiatric labeling in traumatized migrant youth. Greater use of CHRp frameworks—if combined with cultural and ethical caution—may help delay premature diagnoses and favor tailored care. However, the CHRp construct itself remains debated, and its application should not obscure broader systemic biases. Main limitations include the single-case design and the absence of standardized trauma assessments. Therefore, longitudinal research is needed
Proof Beyond the Birthday Bound with the Coupling Technique
No full textInternational audienceThe coupling technique originates from the theory of Markov chains, and allows to upper bound the rate at which a Markov chain approaches its stationary distribution. Recasting the encryption process of a tuple of plaintexts through an iterative block cipher as a Markov chain, it is possible to use this tool to upper bound the advantage of a distinguisher against various kinds of Feistel schemes
Demand Selection for VRP with Emission Quota
No full textInternational audienceCombinatorial optimization (CO) problems are traditionally addressed using Operations Research (OR) methods, including metaheuristics. In this study, we introduce a demand selection problem for the Vehicle Routing Problem (VRP) with an emission quota, referred to as QVRP. The objective is to minimize the number of omitted deliveries while respecting the pollution quota. We focus on the demand selection part, called Maximum Feasible Vehicle Assignment (MFVA), while the construction of a routing for the VRP instance is solved using classical OR methods. We propose several methods for selecting the packages to omit, both from machine learning (ML) and OR. Our results show that, in this static problem setting, classical OR-based methods consistently outperform ML-based approaches
Balanced Feistel Ciphers, First Properties
No full textInternational audienceFeistel ciphers are named after Horst Feistel who studied these schemes in the 1960s. In this chapter, we will only present classical Feistel ciphers, i.e., balanced Feistel ciphers with the group law (Xor). In Chaps. 8, 9, and 10, we will see that there are many variants of these ciphers
Does the Measured Abundance Suggest a Biological Origin for the Ancient Alkanes Preserved in a Martian Mudstone?
No full textInternational audienceThe measured abundance (30–50 ppb) of long-chain (C 10 –C 12 ) alkanes and their possible carboxylic acid precursors found in the ancient Cumberland mudstone in Gale Crater would have been substantially higher before the onset of exposure to ionizing radiation approximately 80 million years ago. Based on recent radiolysis experiments, we estimate conservatively that the Cumberland mudstone would have contained 120–7700 ppm of long-chain alkanes and/or fatty acids before ionizing radiation exposure. Such a high concentration of large organic molecules in martian sedimentary rocks cannot be readily explained by the accretion of organics from carbon-rich interplanetary dust particles and meteorites, nor by the deposition of hypothetical haze-derived organics from an ancient martian atmosphere. We discuss the feasibility of two additional mechanisms––one abiotic and one biological––that could have been capable of depositing this level of long-straight-chain organic molecules in the ancient martian mudstones: allochthonous transport of hydrothermally synthesized organics and autochthonous accumulation of organics from a hypothetical ancient Mars biosphere. To advance and test these and any additional working hypotheses put forth to explain such high concentrations of primary organics on Mars requires an understanding of the radiolytic degradation products expected for organics preserved in mineralogically comparable mudstones
Design, Synthesis and Characterization of a Methoxyhydrazide‐Based Copper(II)–Schiff Base Complex: Investigation of Peroxidase‐Mimetic Behaviour, DNA/BSA‐Binding Interactions, Molecular Docking and Cytotoxic Potential Against HeLa Cells
No full textInternational audienceABSTRACT A mononuclear Cu(II)–Schiff base complex, indicated as MBMBC, has been synthesized from a methoxyhydrazide‐based ligand (HL), ( E )‐ N ′‐(5‐bromo‐2‐hydroxy‐3‐methoxybenzylidene)‐4‐methoxybenzohydrazide. The structure of the complex was determined by single‐crystal X‐ray diffraction analysis, which revealed that the Cu(II) centre is chelated by two oxygen and one imine nitrogen atom of the deprotonated ligand, an aquo and a nitrate ion to form a distorted square pyramidal geometry around the metal. The catalytic activity of the MBMBC complex was assessed for peroxidase‐like oxidation reactions involving o ‐phenylenediamine (OPD), 3,3′‐diaminobenzidine (DAB) and pyrogallol in methanol, using hydrogen peroxide (H 2 O 2 ) as the oxidant. The complex also showed strong binding affinity towards calf thymus DNA (CT‐DNA) and bovine serum albumin (BSA), as confirmed by UV–vis absorption spectroscopy. Significant fluorescence quenching of both the DNA–ethidium bromide (EB) complex and BSA was observed upon addition of the complex MBMBC, suggesting effective binding interactions. To support the experimental findings, molecular docking studies were performed to determine the binding site and interaction energies. Furthermore, the anticancer potential of the MBMBC complex was assessed on the cervical cancer cell line (HeLa) via an in vitro MTT assay, demonstrating its promising cytotoxic activity. Flow cytometry analysis using Annexin V/PI was performed to determine the mode of cell death, which was again reinforced by Hoechst 33342 staining. Generation of reactive oxygen species (ROS) was also envisaged using DCFH‐DA. All these data together suggested that the complex MBMBC is demonstrating a potential anticancer effect
Genomic determinants of Bacillus cereus and outcomes of infection in preterm neonates: a multicentre retrospective study
No full textInternational audienceObjectives: Bacillus cereus sensu lato (s.l.) or B. cereus group increasingly causes severe infections in preterm neonates. However, species-level identification and virulence characterization remain limited. This study aimed to identify B. cereus group species responsible for invasive infections in preterm neonates and to correlate genomic virulence profiles with clinical outcomes.Methods: We conducted a retrospective, multicentre study across 13 French hospitals (2010-2021), including 40 B. cereus group isolates from blood or cerebrospinal fluid of preterm neonates with invasive infections. Clinical data were extracted from patient records. Whole-genome sequencing (WGS) (Illumina and Oxford Nanopore) with hybrid assemblies enabled species identification using digital DNA-DNA hybridization and average nucleotide identity. Virulence genes were screened against a curated database of 65 virulence genes, and associations with clinical outcomes were analysed.Results: Forty isolates were analysed, 42.5% (17 of 40) of patients developed septic shock, and 37.5% (15 of 40), died, usually after rapid clinical deterioration. WGS identified seven species, predominantly Bacillus paranthracis (47.5%, 19 of 40) and B. cereus sensu stricto (20%, 8 of 40). Virulence gene content varied by species. The presence of hblCDAB (60%, 9 of 15), nprB (46.5%, 7 of 15), asbABCDEF (80%, 12 of 15), and essC-cereus/esxA (66.7%, 10 of 15) genes correlated with mortality (p 0.00015, 0.002, 0.0027, and 0.02, respectively). B. cereus sensu stricto carried more virulence determinants and was associated with higher mortality than B. paranthracis and other species, at day 7 (p 0.05) and at day 28 (p 0.0065). The cesH gene (60%, 15 of 25) is significantly associated with survival (p 0.007), particularly with B. paranthacis, the predominant species in our cohort.Conclusions: Invasive B. cereus group infections in preterm neonates are associated with high mortality, particularly in cases due to B. cereus sensu stricto. WGS enables precise species identification and virulence profiling, which are essential insights for diagnostic refinement, outbreak control, and risk stratification in neonatal intensive care settings
Detection of Oscillations in a Type I X-Ray Burst of 4U 0614+091 with SVOM/ECLAIRs
No full textInternational audienceOn 2025 January 10, a thermonuclear (Type I) X-ray burst from the neutron star low-mass X-ray binary (LMXB) 4U 0614+091 was detected with the ECLAIRs instrument on board the Space-based multiband astronomical Variable Object Monitor mission. We present here a time-resolved spectroscopic analysis of the burst, along with the detection of burst oscillations within a 51 s interval during the decay phase. The oscillation frequency is measured to be ν = 413.674 ± 0.002 Hz, consistent with previous reports. However, we detect a significant downward frequency drift over the burst duration, characterized by ν̇=(−4.7±0.3)×10−3Hzs−1. This frequency evolution is atypical compared to those observed in similar burst oscillation sources. We tentatively attribute the observed drift to a Doppler shift induced by orbital motion. Under this interpretation, the inferred orbital period must be shorter than 20 minutes, placing 4U 0614+091 among the most compact known LMXBs