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Central Kurdish text-to-speech and its application in speech-to-text translation
No full textInternational audienceIn this study, we show how to develop high-quality TTS models for low-resource scenarios that according to our extensive evaluation are competitive with the models trained on dedicated TTS data recorded in the studio. We develop three Text-to-Speech (TTS) models for Central Kurdish as a low-resource language using F5-TTS architecture. The models are trained on Central Kurdish TTS datasets in which two of them are curated from audiobooks during this study and the third one is evaluated for the first time. We also demonstrate the potential of TTS models for developing other speech technologies in low-resource languages by proposing a speech synthesis framework used in a speech-to-text translation application, achieving promising results on standard speech translation benchmarks.The dataset and models are publicly available under the CC BY-NC-ND 4.0 license.</div
Dynamic Permeability of Fractal Porous Media
No full textInternational audienceThis work is devoted to theoretical and experimental studies of acoustic waves in air-saturated fractal porous media. The theoretical model of oscillatory flow through a porous medium is based on the concept of a fractal continuum in a non-integer dimensional space. This model allows us to obtain analytical solutions for the velocity field and frequency-dependent permeability. Accordingly, static and dynamic permeability are expressed as functions of fractal dimension numbers and characteristic length scales. To validate theoretical findings, we conducted two independent acoustic experiments with polyurethane open-cell foams having a fractal pore structure. High-frequency ultrasound measurements (in the range of tens to hundreds of kHz) were used to evaluate the fractal properties of the studied foams. The fractal parameters were determined by fitting the signals transmitted from the foam to theoretical output signals. These parameters were then used to predict the static permeability k0. We found that the predicted values of k0 are in good agreement with the ex perimental values obtained in low-frequency long acoustic waveguide (a few hundred Hz range) experiments. Thus, this work provides a robust and physically meaningful framework for describing acoustic wave propagation in fractal porous materials
Time discretization of BSDEs with singular terminal condition using asymptotic expansion
No full textWe consider a class of backward stochastic differential equations (BSDEs) with singular terminal condition and develop a numerical scheme to approximate their solution. To this end, we extend an asymptotic development of the BSDE solution known from the power case, which arises from optimal liquidation problems, to more general generators. This expansion allows to obtain a suitable approximation of the BSDE solution close to the terminal time. Using this as a terminal condition, we analyze the error of a backward Euler implicit scheme and detail its dependence on the terminal condition
Learning Experience in Hybrid Environments: Towards the Identification of Evaluation Criteria
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From Unemployment to Self-Employment: An Evaluation of Self-Employment Assistance Programs
No full textInternational audienceThis paper evaluates self-employment assistance (SEA) programs, which are government initiatives extending the unemployment insurance system to support unemployment to self-employment transitions. Using a general equilibrium model of the US labor market, we show that these programs have important labor market mobility effects and increase the self-employment rate. They also significantly impact the composition and performance outcomes of self-employment: while lump-sum subsidies select low-skilled individuals, SEA programs contingent on previously employed earnings select skilled and wealthier individuals. At the aggregate level, the latter programs mainly reallocate individuals from employment to self-employment, leaving the unemployment rate largely unaffected
Vers une géographie des mobilités reproductible : Enjeux et apports du standard GTFS pour l'analyse de l'offre de transport en commun
No full textInternational audienceLes données GTFS (General Transit Feed Specification) constituent un format standardisé décrivant l’ensemble des services de transport public (bus, tramway, métro, train, autocar...) à travers leurs itinéraires, horaires et arrêts géolocalisés. Initialement développées pour l’information des usagers, ces données produites et mises à disposition par les autorités organisatrices de mobilité représentent une nouvelle source pour l’observation, la modélisation et la comparaison des réseaux de transport en commun.La standardisation de l’offre théorique des réseaux de transport favorise l’analyse multi-échelles des mobilités (urbaine, interurbaine, régionale ou nationales), autorise des comparaisons entre réseaux ou opérateurs et rend possible la mise en oeuvre de flux de traitement automatisés et reproductibles. De plus, la richesse temporelle du GTFS renouvelle les approches classiques de l’accessibilité : au-delà de la seule accessibilité spatiale des infrastructures, il devient possible de quantifier et d’analyser l’offre temporelle (fréquences, amplitudes horaires, connexions, correspondances, vitesses...) et d’intégrer les rythmes quotidiens dans la compréhension des réseaux.L’objectif de cette communication est de questionner la manière dont ce format de données, en rendant les informations de transport plus accessibles, comparables et exploitables, contribue à l’émergence d’une nouvelle géographie des mobilités, ouverte et reproductible, où l’espace et le temps sont envisagés comme des dimensions indissociables de l’analyse des déplacements.Après avoir présenté la genèse et le fonctionnement du format GTFS, la communication montrera comment son usage renouvelle les pratiques d’analyse spatiale et la production d’indicateurs d’offre et d’accessibilité plus fins et contextualisés. Elle présentera plusieurs exemples d’analyses à différentes échelles et sur différents modes de transport ainsi qu’un workflow d’analyses automatisées (en python). Enfin, elle discutera des apports méthodologiques de ce standard, tout en soulignant ses limites et les défis liés à la qualité des jeux de données, la modélisation de l’offre et l’utilisabilité de ces données dans des contextes de recherche
GWTC-4.0: Updating the Gravitational-Wave Transient Catalog with Observations from the First Part of the Fourth LIGO-Virgo-KAGRA Observing Run
No full textInternational audienceVersion 4.0 of the Gravitational-Wave Transient Catalog (GWTC-4.0) adds new candidates detected by the LIGO, Virgo, and KAGRA observatories through the first part of the fourth observing run (O4a: 2023 May 24 15:00:00 to 2024 January 16 16:00:00 UTC) and a preceding engineering run. In this new data, we find 128 new compact binary coalescence candidates that are identified by at least one of our search algorithms with a probability of astrophysical origin and that are not vetoed during event validation. We also provide detailed source property measurements for 86 of these that have a false alarm rate < 1 \rm{yr}^{-1}. Based on the inferred component masses, these new candidates are consistent with signals from binary black holes and neutron star-black hole binaries (GW230518_125908 and GW230529_181500). Median inferred component masses of binary black holes in the catalog now range from (GW230627_015337) to (GW231123_135430), while GW231123_135430 was probably produced by the most massive binary observed in the catalog. For the first time we have discovered binary black hole signals with network signal-to-noise ratio exceeding 30, GW230814_230901 and GW231226_01520, enabling high-fidelity studies of the waveforms and astrophysical properties of these systems. Combined with the 90 candidates included in GWTC-3.0, the catalog now contains 218 candidates with and not otherwise vetoed, doubling the size of the catalog and further opening our view of the gravitational-wave Universe
Twin pregnancy with the first twin in breech presentation: Survival and neurodevelopmental outcome of preterm infants at a corrected age of 2 years
No full textInternational audienceObjectives: To compare survival and neurodevelopmental outcomes at 2 years' corrected age for preterm twins (≤33 +0 weeks) with the first twin in breech presentation, according to planned mode of delivery (planned vaginal delivery [PVD] vs planned caesarean delivery [PCD]). Secondary objectives were survival at discharge, survival without morbidity at discharge, neonatal outcomes, and maternal morbidity. Methods: We conducted a retrospective cohort study of women with preterm breech first twins born after preterm labour (≤33 +0 weeks) at Nantes University Hospital (2008-2019). A propensity score estimated each mother's risk of caesarean. Outcomes (survival at discharge, survival at discharge without morbidity, and survival with normal neurodevelopment at 2 years) were adjusted for gestational age, sex, and propensity score. Sensitivity analyses included multiple imputation for missing data and exclusion of births < 26 +0 weeks. Results: Among 413 preterm twin deliveries, 61 women were included: 15 in the PVD group (30 newborns) and 46 in the PCD group (92 newborns). After adjustment for propensity score and gestational age, no significant differences were observed in survival at discharge (aOR 1.9, 95 % CI 0.28-12.7, P = 0.51) or survival without morbidity (aOR 0.3, 95 % CI 0.06-2.21, P = 0.27). Survival with normal neurodevelopment at 2 years trended lower with PVD (aOR 0.3, 95 % CI 0.07-1.22, P = 0.09). Maternal morbidity was higher in the PCD group. Conclusion: Planned mode of delivery did not significantly influence survival in preterm breech-first twins, but confidence intervals were wide. A trend toward poorer neurodevelopment at 2 years was observed after planned vaginal delivery, whereas maternal morbidity was higher after planned caesarean delivery. These findings support individualized decision-making, balancing neonatal and maternal risks.</div
No evidence of bowhunting in Magdalenian antler points: Comment on Langley and Lombard (2025)
No full textInternational audienceIn the study of prehistoric projectile points, the tip cross-sectional area method (TCSA) is often used to hypothesize about projectile delivery mode. In a recent article, Langley and Lombard applied this method, combined with point mass, to Magdalenian antler points from southwest France. Their results suggest the likelihood of bowhunting at some sites, and one point subtype, the Lussac-Angles point, is particularly highlighted as possible arrow tip because of its low TCSA and mass. However, the methods used in this study underestimate TCSA and mass, particularly when composite weapon tips are considered. Experimental evidence shows that Lussac-Angles points can be used with the spearthrower, and there is also archeological and experimental evidence of use with the spearthrower for fork-based points, another type of Magdalenian antler point that has a TCSA similar to the Lussac-Angles points. These findings refute the evidence of bowhunting in Magdalenian antler points and offer another example of the problems raised by the use of the TCSA method to reconstruct past weapon systems
Protective Effects of Neutral Lipids from Phaeodactylum tricornutum on Palmitate-Induced Lipid Accumulation in HepG2 Cells: An In Vitro Model of Non-Alcoholic Fatty Liver Disease
No full textInternational audienceNon-alcoholic fatty liver disease (NAFLD), often associated with obesity, has become a serious public health matter. NAFLD is characterized by an excessive lipid accumulation in hepatocytes, mainly stored as triglycerides. The marine microalga Phaeodactylum tricornutum is well known for its richness of bioactive compounds, particularly lipids. Therefore, different natural lipid extracts from P. tricornutum are deciphered to jugulate or prevent obesity leading to NAFLD. In this study, the main focus was on the effects of purified neutral and polar lipid extracts from P. tricornutum in a cellular model of NAFLD. Human HepG2 cells were used and exposed for 24 h to 250 μM palmitate to induce NAFLD with or without microalgal lipid extracts. Data showed that neutral lipid extract presented lower viability and cytotoxic activities on HepG2 at 75 µg/mL. The impact on apoptosis was around 5% and below the threshold. Nevertheless, the use of neutral lipid at 50 µg/mL induced a decrease in the number and size of lipid droplets, and so, preventing NAFLD. On the contrary, the polar lipid extract had no effect on the accumulation of triglycerides in HepG2 cells. To conclude, neutral lipid extract seemed to be a good candidate to prevent NAFLD