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Generic Attacks on Classical Feistel Ciphers with Internal Permutations
No full textInternational audienc
Multi-laboratory compilation of atmospheric carbon dioxide data for the period 1983-2024; obspack_ch4_1_GLOBALVIEWplus_v8.0_2026-01-13
No full textInternational audienceThis product is constructed using the Observation Package (ObsPack) framework [Masarie et al., 2014; www.earth-syst-sci-data.net/6/375/2014/]. The framework is designed to bring together atmospheric greenhouse gas (GHG) observations from a variety of sampling platforms, prepare them with specific applications in mind, and package and distribute them in a self-consistent and well-documented product. ObsPack products are intended to support GHG budget studies and represent a new generation of cooperative value-added GHG data products. This product includes 535 atmospheric methane datasets derived from observations made by 68 laboratories. Data for the period 1983-2024 (where available) are included
Generic Attacks on Generalized Feistel Ciphers
No full textInternational audienceType-1, type-2 and type-3 and alternating Feistel schemes are described by Zhen et al. (1990) (see also Hoang and Rogaway 2010). These generalized Feistel schemes are used in well-known block cipher networks that use generalized Feistel schemes: CAST-256 (type-1), RC-6 (type-2), and BEAR/LION (alternating). Also, type-1 and type-2 Feistel schemes are respectively used in the construction of the hash functions and . There exist many kind of attacks on these schemes: impossible differential attacks (Bouillaguet et al. 2012; Luo et al. 2014), boomerang attacks (Choy and Yap 2009), and differential attacks (Nachef et al. 2013). However, the attacks we are going to describe in this chapter generally allow to attack more rounds (or at least the same number of rounds) than for example impossible differential attacks. Moreover in the presented attacks, there is no restriction on the round function, unlike for some impossible differential attacks where it is supposed to be bijective. Security results are given in Hoang and Rogaway (2010)
Real-World Use of Botulinum Neurotoxin Type A in Post-Stroke Spasticity Between 2015 and 2023: Insights From France
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A Bench Evaluation of the Effects of Circuit Configurations on Instrumental Dead Space During Home Mechanical Ventilation
No full textInternational audienceBackground: A number of circuit configurations can be proposed for implementing mechanical ventilation, most of which are likely to impact the instrumental dead space and thus, on alveolar ventilation. This bench study was designed to investigate the effects of circuit configuration on P CO 2 with constant ventilator settings ( iso-V T condition; V T : tidal volume ) and to evaluate the modifications of V T required to maintain stable alveolar ventilation with each circuit configuration ( iso- P ET CO 2 condition ; end-tidal CO 2 partial pressure being considered as a surrogate for alveolar ventilation). Methods: A total of 17 configurations were evaluated, including valve and leak circuits, heater humidifier or different heat and moisture exchangers, with or without catheter mount, and both invasive and noninvasive situations. All these evaluations were performed at 2 different respiratory rate, both in iso-V T and iso- P ET CO 2 conditions. Results: With valve circuits, modifications of instrumental dead space resulted in P ET CO 2 variations reaching up to 16 mm Hg from one configuration to another. The corresponding increase in the required V T to compensate for the additional dead space reached up to 120 mL. Leak circuits significantly reduced the effects of instrumental dead space compared with valve circuits. Conclusions: Any modification of the circuit configuration requires a systematic reevaluation of ventilation efficiency
Brick Kilns Across India: A Temporal Analysis of Brick Kiln Distribution and Technology Types
No full textInternational audienceThe MuTBriK dataset contains multispectral Sentinel-2 image patches prepared for multi-class semantic segmentation of brick kiln types. Each image consists of 8 channels: six original Sentinel-2 spectral bands and two derived indices (NDVI and NDBI). All bands are normalized. Each image has a corresponding pixel-wise annotation mask. The dataset has been used to generate a national-scale map of brick kiln distribution and technology types across India
Survival after ICU discharge is shaped more by chronic disease than admission severity
No full textInternational audienceBackground: Mortality is high both during intensive care unit (ICU) stay and in the year following discharge, yet factors influencing long-term survival remain poorly defined. We hypothesized that pre-existing chronic conditions may be more strongly associated with post-ICU survival than acute illness severity or admission diagnosis.Methods: This is a post-hoc analysis of the prospective, observational, multicenter FROG-ICU cohort, which included all consecutive patients admitted to 21 French ICUs and followed for one year after discharge. ICU survivors with complete data on admission severity scores (Sequential Organ Failure Assessment [SOFA], Simplified Acute Physiology Score II [SAPS-II]), comorbidities (Charlson Comorbidity Index [CCI]), and cardiovascular/renal biomarkers at discharge (n = 1400) were included. Associations with one-year mortality were assessed using Cox models. Discriminatory performance was evaluated with time-dependent area under the receiver operating characteristic curve (AUC).Results: Among 1548 ICU survivors, 1400 were analyzed (median age 61 years, 63 % male). Admission diagnoses included acute respiratory failure (19 %), septic shock (24 %), and neurologic conditions (16 %). The CCI was the strongest predictor of mortality at day 7 (AUC 0.70 [95 % Confidence Interval [CI], 0.64-0.77]), at 3 weeks (AUC 0.75 [0.69-0.78]), and remained high over one year, outperforming SAPS-II (0.63 [0.54-0.72]) and SOFA (0.61 [0.53-0.68]). Although cardiovascular (NT-proBNP, bio-ADM) and kidney (pNGAL) biomarkers had comparable short-term discriminatory value, CCI performed better for long-term outcomes across different admission diagnoses.Conclusion: In this analysis, pre-existing chronic conditions were primary drivers of short- and long-term survival after ICU discharge, exceeding prognostic value of acute illness severity at admission.Clinical trial registration: French and European Outcome Registry in Intensive Care Units (FROG-ICU) study: ClinicalTrials.govNCT01367093. Registered 3 June 2011
Catégories dérivées, surfaces et localisation
No full textThis doctoral dissertation studies the localization of the topological Fukaya category of a graded marked surface, as defined by Haiden-Katzarkov-Kontsevich, at a collection of compatible spherical objects. Geometrically, such a collection corresponds to a set of disjoint graded simple closed curves on the surface. We seek to motivate the idea that the localized category can play the role of a topological Fukaya category for the singular surface obtained by contracting the corresponding simple closed curves. In the first chapter we recall classical results of the representation theory of gentle algebras and introduce the relevant concepts regarding A∞-categories, before presenting the construction of the topological Fukaya category of a graded marked surface. Some aspects of the geometric model for the bounded derived category of a gentle algebra are also presented. In the second chapter we define a class of algebras given by quivers with relations, that we call pinched gentle algebras. Based on a similar result for gentle algebras, we show that graded pinched gentle quivers are in one-to-one correspondence with marked surfaces with conical singularities endowed with a graded simple admissible dissection. We then study a differential graded (DG) enhancement of the localization of the perfect derived category of a gentle algebra by a subcategory generated by a collection of compatible spherical objects. We show that each pinched gentle algebra arises as the endomorphism ring of a formal generator of such a DG quotient. In order to show the formality, we use a spectral sequence on the morphism spaces of a DG quotient and describe its first page in a general way. Finally, using a result of Gyenge, we deduce that the derived category of a pinched gentle algebra sits in a recollement similar to the one obtained by Chang-Jin-Schroll for the localization at a collection of compatible arcs. The third chapter essentially generalizes the results of the second one by enlarging the class of formal generators obtained for localizations of topological Fukaya categories by compatible spherical objects. More precisely, a generalization of the class of pinched gentle algebras is given, as well as a generalization of the notion of admissible dissection of a marked surface with conical singularities. The one-to-one correspondence between these objects, given in the second chapter, is then described in this new generality. We then study a A∞-enhancement of the triangulated quotient and show that each pinched gentle algebra arises as the endomorphism ring of a formal generator. The computation of the formality is done this time by means of a homotopy transfer of A∞-structure. This construction allows us to associate to a graded marked surfaces with conical singularities S, endowed with an admissible dissection A, a category F_A(S) which generates the perfect derived category of a pinched gentle algebra. An immediate consequence of the equivalences given in the smooth case by Haiden-Katzarkov-Kontsevich is that the Morita equivalence class of F_A(S) is independent of A. We give two bases for pinched gentle algebras along the way, one of which is obtained using Bergman's Diamond Lemma. The last section provides an example of a non-Krull-Schmidt triangulated category containing two silting objects having a different number of indecomposable summands.Cette thèse étudie la localisation des catégories de Fukaya topologique de surfaces marquées graduées, telles que définies par Haiden-Katzarkov-Kontsevich, en une collection d'objets sphériques compatibles. Géométriquement, une telle collection correspond à une famille de courbes fermées simples graduées disjointes sur la surface. Nous chercherons à motiver l'idée que la catégorie localisée peut jouer le rôle d'une catégorie de Fukaya topologique pour la surface singulière obtenue en contractant les courbes fermées simples correspondantes. Dans le premier chapitre, nous rappelons des résultats classiques de la théorie des représentations des algèbres aimables et introduisons les concepts qui nous seront utiles pour les catégories A∞, avant de présenter la construction de la catégorie de Fukaya topologique d'une surface marquée graduée. Certains aspects du modèle géométrique pour la catégorie dérivée bornée d'une algèbre aimable sont également présentés. Dans le deuxième chapitre, nous définissons une classe d'algèbres données par carquois et relations, que nous appelons algèbres aimables contractées. En se basant sur un résultat similaire pour les algèbres aimables, nous montrons que les carquois gradués contractées sont en bijection avec les surfaces marquées avec singularités coniques munies d'une dissection graduée admissible simple. Nous étudions ensuite un enrichissement différentiel gradué (DG) de la localisation de la catégorie dérivée parfaite d'une algèbre aimable par une sous-catégorie engendrée par une collection d'objets sphériques compatibles. Nous montrons que chaque algèbre aimable contractée peut-être réalisé comme anneau d'endomorphisme d'un générateur formel d'un tel quotient DG. Afin de montrer la formalité, nous utilisons une suite spectrale sur les espaces de morphisme d'un quotient DG et nous décrivons sa première page en toute généralité. Enfin, nous déduisons d'un résultat de Gyenge le fait que la catégorie dérivée d'une algèbre aimable contractée prend place dans un recollement similaire à celui obtenu par Chang-Jin-Schroll pour les localisations en une collection d'arcs compatibles. Le troisième chapitre est essentiellement une généralisation des résultats du second, en élargissant la classe des générateurs formels obtenus pour les localisations de catégories de Fukaya topologiques par des objets sphériques compatibles. Plus précisément, une généralisation de la classe des algèbres aimables contractées est donnée, ainsi qu'une généralisation de la notion de dissection admissible d'une surface marquée avec singularités coniques. La bijection entre ces deux classes d'objets, établie au chapitre deux, est alors décrite dans cette nouvelle généralité. Nous étudions ensuite un enrichissement A∞ du quotient triangulé et montrons que chaque algèbre aimable contractée peut-être réalisé comme anneau d'endomorphisme d'un générateur formel. Le calcul de la formalité est effectué cette fois-ci au moyen d'un transfert d'homotopie de structure A∞. Cette construction nous permet d'associer à une surface graduée marquée avec singularités coniques S munie d'une dissection admissible A, une catégorie F_A(S) qui engendre la catégorie dérivée parfaite d'une algèbre aimable contractée. Une conséquence immédiate des équivalences données dans le cas lisse par Haiden-Katzarkov-Kontsevich est que la classe d'équivalence de Morita de F_A(S) est indépendante de A. Nous donnons au passage deux bases pour les algèbres aimables contractées, l'une étant obtenue par une application du lemme du diamant de Bergman. La dernière section donne un exemple de catégorie triangulée non-Krull-Schmidt contenant deux objets bousculants ayant un nombre différent de composantes directes indécomposables
[ 1 H]/[ 2 H] discriminated bianthryl atropisotopomers: enantiospecific syntheses from BINOL and direct multi-spectroscopic analyses of their isotopic chirality
No full textInternational audienceThe synthesis of two [1H]/[2H] discriminated bianthryl atropisotopomers (i.e., isotopically chiral atropisomers, vide infra) with ≥ 97% enantiomeric excess (ee) from the atropisomers of commercial (aS)- and (aR)-1,1′-bi-2-naphthol (BINOL, > 99% ee) is described. The approach is based on enantiospecific [4 + 2] cycloaddition reactions of aryne atropisomer intermediates with [2H4]-furan. Overall, the six-step (from enantiopure BINOL) reaction sequence to the bianthryl atropisotopomers described herein is occurring without significant erosion of the molecular stereogenic information. This is substantiated experimentally by three direct spectroscopic methods that do not necessitate chemical derivatization: i) mirror specific optical rotations as a proof of optical activity and also aproof of their equivalent ee, ii) mirror vibrational circular dichroism (VCD) spectra as a proof of their equivalent ee and for the confirmation of their absolute configurations (AC), and, iii) for the first time, anisotropic 2H/13C NMR in lyotropic chiral liquid crystals for the determination of their ee for one of them. In a broader and foreseeable perspective, the enantiospecific synthetic approach considered in this work to access bianthryl atropisotopomers from BINOL is simple and scalable, which should enable the production of a diverse range of atropisotopomers in a near future, possibly embedding never examined isotopes (e.g., [3H]). The availability of this class of isotopically chiralcompounds in high isotopic and enantiomeric purity is a real asset for the development of precision chiral spectroscopies
Physical Processes Driving Carbon Subduction in the Southern Ocean in an Eddy‐Permitting Model
No full textInternational audienceThe Southern Ocean south of 35°S represents a small source of natural inorganic carbon for the atmosphere but a major sink of anthropogenic carbon. The magnitude of the inorganic carbon sink, and the sequestration of inorganic and organic carbon strongly depend on the rate at which they are subducted below the mixed layer. We use a global ocean model at 0.25°resolution to quantify the drivers of the pathways of total and anthropogenic dissolved inorganic carbon (DIC) and organic carbon (OC) across and within the time-varying mixed layer of five physically consistent regions of the Southern Ocean over the period 1995-2014. Total DIC is brought into the mixed layer through obduction south of the Antarctic Circumpolar Current (ACC) and subducted north of the ACC, resulting in a net obduction of 11.2 PgC/year, with advective processes being responsible for about two-thirds of the total transfer. Anthropogenic carbon is brought to the mixed layer through the ocean surface in all regions but mainly subducted north of the ACC, with the subduction (1.05 PgC/ year) being achieved through both advection and diffusion, each dominating respectively north and south of the Subantarctic Front. Two thirds of the organic carbon are subducted through the gravitational pump (1.9 PgC/ year) and one-third through physical transfer (0.9 PgC/year), with an equivalent contribution from advection and diffusion. At the local scale, advective fluxes largely dominate other physical processes in transferring carbon across the base of the mixed layer, and are found to be increased near topographic features and boundary currents