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Association between chronic long-term exposure to airborne dioxins and breast cancer
No full textInternational audienceBreast cancer is the most common type of cancer among women. Environmental pollutants, specifically those with endocrine disrupting properties like dioxins, may impact breast cancer development. Current epidemiological studies on the association between exposure to dioxins and the risk of breast cancer show inconsistent results. To address these uncertainties, our objective was to investigate the impact of airborne dioxin exposure on breast cancer risk within the E3N cohort, encompassing 5222 cases identified during the 1990–2011 follow-up and 5222 matched controls. Airborne dioxin exposure was assessed using a Geographic Information System-based metric considering residential proximity to dioxin emitting sources, their technical characteristics, exposure duration and wind direction. Additional analyses were performed using dioxin concentrations estimated by a chemistry transport model, CHIMERE. The results suggest a slightly increased risk between cumulative dioxin exposure at the residential address and overall breast cancer risk (adjusted odds ratio (OR) = 1.03, 95% confidence interval (CI): 0.99–1.07, for a one standard deviation (SD) increment among controls (14.47 log-μg-TEQ/m2). The associations remained consistent for sources within 3, 5, and 10 km, and when restricting exposure to dioxin emissions from household waste incinerators. Similar OR estimates (OR = 1.02, 95% CI: 0.97–1.07, for a one SD increment) were obtained using the CHIMERE model. The findings of this study suggest the possibility of an increased risk of breast cancer associated with long-term residential exposure to dioxins and emphasize the importance of efforts to mitigate air pollution exposure
Chitosan surface interaction platform for protein binding quantification by fluorescence microscopy, application to the specificity of CBD proteins
No full textInternational audienceSurface-proteins interactions play key roles in many domains such as biomedicine, nanotechnology and the biology of plant-insect interactions. This article proposes a platform that allows to quantify surface interaction of proteins with chitin and chitosans to further discriminate and study specific interactions of proteins with chitin-binding domains (CBD). The platform consists in covalently grafted chitosan thin films of various degrees of acetylation (DA) through surface silanisation, spin-coating and water-temperature treatment. The obtained films were thoroughly characterized by infrared spectroscopy, contact angle measurements, atomic force microscopy and wide and small-angle X-ray scattering. Protein affinity to coated surfaces of reacetylated chitosans with degrees of acetylation ranging from 0.5 % to 76 % was evaluated by fluorescence microscopy. The specific affinity of lectins with a CBD was evidenced in comparison to proteins without CBD. As expected, the affinity was stronger at higher DAs, suggesting that the acetylation pattern play a part in specific lectin binding. In conclusion, chitosan films were fully characterized, and the elaborated platform shows promising results in screening protein interactions to chitin. This protein interaction platform is reportedly the first method able to differentiate the interactions of proteins containing a CBD and proteins which do not contain one, with whole chain “chitin-like” chitosans, by means of a simple and direct fluorescent microscopy quantification. This platform could further be used for other types of chitin-binding proteins or applied to other polysaccharide-protein interactions
FQ-06. Magnetic position determination with giant-magnetoresistance and moving field-free point in catheter
No full textInternational audienceX-ray fluoroscopic imaging is the standard method to obtain catheter position during catheterization procedures, a minimally invasive surgery for diagnostic and treatment of the vascular network [1]. However, this method exposes both patients and doctors to ionizing radiation. To address this issue, we propose a new method to track the catheter by installing a magnetic sensor at the catheter tip and generating a known magnetic field (MF) around the operative zone. Due to the mandatory small size of the catheter, we utilized micrometer-sized giant magnetoresistance (GMR) sensors for this tracking system [2, 3]. GMR sensors require only two connection wires, have a wide bandwidth that allows flexibility in selecting the working frequency and can detect low-intensity MFs down to the nano Tesla range [4]. In this work, a 300µm x 700µm GMR chip (shown Fig.1a) is prepared and installed on a catheter to show the integration feasibility. The presented results are obtained with GMRs connected in a Wheatstone bridge configuration in a larger chip (shown Fig.1b) for ease of manipulation. Both present a similar magnetic response. Our novel tracking method is based on the time detection of a moving null MF, known as the Field-Free Point (FFP) inspired by Magnetic Particle Imaging (MPI) [5]. Rather than measuring the MF intensity to compute the position [6], the time detection of the FFP gives the information on the position. We constructed an experimental setup to demonstrate the feasibility of this method in one dimension [7]. On a 1D setup, along a line from -15cm to 15cm, we measure the positions and standard variations every cm. The results are shown in Fig 2. The average of all standard deviation is 1.3mm with an average deviation from the actual position of 4.9% showing promising results for further steps
Utilisation de la théorie des valeurs extrêmes pour la meilleure prise en copte des pics de demande lors de la génération de périodes types par aggregation pour l'optimisation de la conception des réseaux de chauffage urbain
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Persistence, extinction and spreading properties of non-cooperative Fisher--KPP systems in space-time periodic media
No full textInternational audienceThis paper is concerned with asymptotic persistence, extinction and spreading properties for non-cooperative Fisher-KPP systems with space-time periodic coefficients. Results are formulated in terms of a family of generalized principal eigenvalues associated with the linearized problem. When the maximal generalized principal eigenvalue is negative, all solutions to the Cauchy problem become locally uniformly positive in long-time, at least one space-time periodic uniformly positive entire solution exists, and solutions with compactly supported initial condition asymptotically spread in space at a speed given by a Freidlin-Gärtner-type formula. When another, possibly smaller, generalized principal eigenvalue is nonnegative, then on the contrary all solutions to the Cauchy problem vanish uniformly and the zero solution is the unique space-time periodic nonnegative entire solution. When the twogeneralized principal eigenvalues differ and zero is in between, the long-time behavior depends on the decay at infinity of the initial condition. The proofs rely upon double-sided controls by solutions of cooperative systems. The control from below is new for such systems and makes it possible to shorten the proofs and extend the generality of the system simultaneously
Loop torsors. theory and applications
No full textInternational audienceLoop torsors over Laurent polynomial rings in characteristic 0 were originally introduced in relation to infinite dimensional Lie theory. Applications to other areas require a theory that can yields results in positive characteristic, and for group schemes that are not of finite type. The relation between loop and so-called toral torsors, is one of the central questions in the area. The present paper addresses this question in full generality
Tailoring sub-5 nm Fe-doped CeO2 nanocrystals within confined spaces to boost photocatalytic hydrogen evolution under visible light
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Refining the evaluation of speech synthesis: A summary of the Blizzard Challenge 2023
No full textInternational audienceThe Blizzard Challenge has benchmarked progress in Text-to-Speech (TTS) since 2005. The Challenge has seen important milestones passed, with results suggesting that synthetic speech was indistinguishable from natural speech in terms of intelligibility in 2021 and that by that same year it was perhaps even indistinguishable in naturalness. The high quality of synthetic speech generated by the latest TTS systems has thus revealed limitations with ITU-T P.800.1 Mean Opinion Score (MOS) in detecting the remaining differences between synthetic and natural speech. Yet, it was the only method used in previous Challenges and is still the most popular method in the field for speech synthesis evaluation. In the 2023 Challenge, we addressed observed limitations of past Challenges by incorporating state-of-the-art speech synthesis evaluation techniques to refine the evaluation of speech quality, speaker similarity and intelligibility. For speech quality, a relative comparison of the systems receiving the best MOS was able to discover a greater number of significant differences between systems. Regarding speaker similarity, we demonstrated that there is a strong bias depending on whether the listeners are familiar with the target voice or not. As for intelligibility, the evaluation of language-specific phenomena, such as the pronunciation of homographs, better highlighted system limits compared to global transcription tasks of synthesised utterances. In addition to reporting results for the 18 entries to the 2023 Challenge, we extend the results analysis to type of TTS module to provide some insights on the most recent advances in model design. Overall, this year's results demonstrate the need for a shift towards new methods for refining TTS evaluation to shed light on increasingly smaller and localised differences between synthesised and natural speech
