Fast in-place accumulated bilinear formulae

Bilinear operations are ubiquitous in computer science and in particular in computer algebra and symbolic computation. One of the most fundamental arithmetic operation is the multiplication, and when applied to, e.g., polynomials or matrices, its result is a bilinear function of its inputs. In terms of arithmetic operations, many sub-quadratic (resp. sub-cubic) algorithms were developed for these tasks. But these fast algorithms come at the expense of (potentially large) extra temporary space to perform the computation. On the contrary, classical, quadratic (resp. cubic) algorithms, when computed sequentially, quite often require very few (constant) extra registers. Further work then proposed simultaneously ``fast'' and ``in-place'' algorithms, for both matrix and polynomial operations We here propose algorithms to extend the latter line of work for accumulated algorithms arising from a bilinear formula. Indeed one of the main ingredient of the latter line of work is to use the (free) space of the output as intermediate storage. When the result has to be accumulated, i.e., if the output is also part of the input, this free space thus does not even exist. To be able to design accumulated in-place algorithm we thus relax the in-place model to allow algorithms to also modify their input, therefore to use them as intermediate storage for instance, provided that they are restored to their initial state after completion of the procedure. This is in fact a natural possibility in many programming environments. Furthermore, this restoration allows for recursive combinations of such procedures, as the (non concurrent) recursive calls will not mess-up the state of their callers. We propose here a generic technique transforming any bilinear algorithm into an in-place algorithm under this model. This then directly applies to polynomial and matrix multiplication algorithms, including fast ones

Epitaxy of SrTiO3 on Silicon: The Knitting Machine Strategy

Saint-Girons, Guillaume et al.SrTiO3 (STO) crystalline layers grown on Si open unique perspectives for the monolithic integration of functional oxides in silicon-based devices, but their fabrication by molecular beam epitaxy (MBE) is challenging due to unwanted interfacial reactions. Here we show that the formation of single-crystal STO layers on Si by MBE at the moderate growth temperature imposed by these interface reactions results from the crystallization of a partially separated amorphous mixture of SrO and TiO2 activated by an excess of Sr. We identify the atomic pathway of this mechanism and show that it leads to an antiphase domain morphology. On the basis of these results, we suggest and test alternative STO growth strategies to avoid antiphase boundary formation and significantly improve the STO structural quality. The understanding provided by these results offers promising prospects to crystallize perovskite oxides on semiconductors at moderate temperature and circumvent the issue of parasitic interface reactions.This work was partly supported by the European projects SITOGA (STREP FP7, grant number 619456) and TIPS (ICT H2020, grant number 107347) as well as by the French ANR programs HIRIS and DIAMWAFEL.Peer reviewe

Behavior learning using emotional conditioning

International audienceWe present a novel way to design a control system for a robot, using emotions as a way to produce richer internal states. We believe that using a single scalar as an evaluation of the quality of the policy and stating that the goal of the agent is to gather reward, as it is proposed by reinforcement learning, is not an appropriate granularity for creating an autonomous control system : even with a fine-tuned reward function, efficient on a specific task, it is often impractical to derive any useful knoweldge from it in order to build more flexible, neuromimetics control systems. A complete shift of paradigm is necessary for a bottom up approach\,: the robot is given pain and pleasure perception circuits and we examine how emotions arise and are the basis for respondant and operant conditioning. Inspired from the cerebral circuits of superior mammals responsible of this behavior, we propose an implementation in an autonomous robot using models of adaptive neural networks

The soucoupes of the Observatoire cave (Principality of Monaco): contribution to the study of the Large flake phenomenon in the early Palaeolithic

Les fouilles de la grotte de l’Observatoire (Principauté de Monaco), remarquablement publiées dans le premier tome des Archives de l’Institut de Paléontologie Humaine en 1927, avaient révélé la présence dans le « foyer k » d’une vieille industrie composée d’éclats en calcaire de très grandes dimensions, autrement appelés soucoupes par Léonce de Villeneuve. La reprise pour étude de cet assemblage lithique (n =132) indique une recherche d’éclats normalisés, de morphologie trapézoïdale à quadrangulaire, débités aux dépens de volumes soigneusement sélectionnés, aménagés et exploités selon un débitage préférentiel à séquence unique. Ces grands éclats, structurés autour d’un biseau cortical brut de débitage, fin, biplan, rectiligne à légèrement convexe, recouvrent la définition du hachereau d’un point de vue techno-fonctionnel. Cette collection de la grotte de l’Observatoire, également composée de galets manuportés (N =159) et d’un biface, aurait un âge antérieur à 230 000 ans BP. À ce jour, cette série ne trouve aucun équivalent régional mais des rapprochements peuvent être effectués avec les « Large flakes industries » d’Espagne et d’Afrique du Nord, caractérisées par un débitage d’entames et la présence de hachereaux de type 0. Les soucoupes de la grotte de l’Observatoire conduisent à nous interroger sur les spécificités de cette technologie macrolithique et sur sa signification dans un contexte régional et méditerranéen. Notre étude nous amène finalement à discuter de l’hypothèse de la diffusion pour envisager celle d’une apparition locale, dans le cadre d’un savoir-faire technique qui se serait étroitement adapté à la nature du matériau d’œuvre.The excavations at the Observatoire Cave (Principality of Monaco), have been well published in the first volume of the Archives of the Institut de Paleontologie humaine in 1927. The authors document the presence in the « foyer k » of large flakes also called soucoupes (saucers or flying saucers in french) by L. de Villeneuve. The study of this lithic collection (N=132) indicates a production of trapezoidal to quadrangular flakes, detached on limestone cobbles that were cautiously selected, prepared and shortly exploited for one unique preferential product. These large flakes have been structured on a cortical distal end (or biseau), never retouched and characterized by a fine angle, a biplane section and a slightly convex delineation. In a techno-functional perspective, these large flakes clearly overlap the definition of the cleavers. This collection from the Observatoire Cave, which precedes 230 000 BP, also includes a series of cobbles (n=159) and one single handaxe. This lithic assemblage finds no regional equivalent, but comparisons can be made with some Acheulean large flake Industries from Spain and Northern Africa, characterized by a production of entames and the shaping of proto-cleavers (or type 0). The soucoupes of the Observatoire Cave encourage us to develop further on the peculiarities of this macrolithic technology and on their signification in a regional and Mediterranean context. Our study finally challenges the hypothesis of diffusion and consider the scenario of a local invention as plausible, within a framework of a technology that was closely adapted to the nature of the raw material

Les soucoupes de l’Observatoire (Principauté de Monaco) : contribution à l’étude du phénomène des grands éclats au Paléolithique ancien

Les fouilles de la grotte de l’Observatoire (Principauté de Monaco), remarquablement publiées dans le premier tome des Archives de l’Institut de Paléontologie Humaine en 1927, avaient révélé la présence dans le « foyer k » d’une vieille industrie composée d’éclats en calcaire de très grandes dimensions, autrement appelés soucoupes par Léonce de Villeneuve. La reprise pour étude de cet assemblage lithique (n =132) indique une recherche d’éclats normalisés, de morphologie trapézoïdale à quadrangulaire, débités aux dépens de volumes soigneusement sélectionnés, aménagés et exploités selon un débitage préférentiel à séquence unique. Ces grands éclats, structurés autour d’un biseau cortical brut de débitage, fin, biplan, rectiligne à légèrement convexe, recouvrent la définition du hachereau d’un point de vue techno-fonctionnel. Cette collection de la grotte de l’Observatoire, également composée de galets manuportés (N =159) et d’un biface, aurait un âge antérieur à 230 000 ans BP. À ce jour, cette série ne trouve aucun équivalent régional mais des rapprochements peuvent être effectués avec les « Large flakes industries » d’Espagne et d’Afrique du Nord, caractérisées par un débitage d’entames et la présence de hachereaux de type 0. Les soucoupes de la grotte de l’Observatoire conduisent à nous interroger sur les spécificités de cette technologie macrolithique et sur sa signification dans un contexte régional et méditerranéen. Notre étude nous amène finalement à discuter de l’hypothèse de la diffusion pour envisager celle d’une apparition locale, dans le cadre d’un savoir-faire technique qui se serait étroitement adapté à la nature du matériau d’œuvre.The excavations at the Observatoire Cave (Principality of Monaco), have been well published in the first volume of the Archives of the Institut de Paleontologie humaine in 1927. The authors document the presence in the « foyer k » of large flakes also called soucoupes (saucers or flying saucers in french) by L. de Villeneuve. The study of this lithic collection (N=132) indicates a production of trapezoidal to quadrangular flakes, detached on limestone cobbles that were cautiously selected, prepared and shortly exploited for one unique preferential product. These large flakes have been structured on a cortical distal end (or biseau), never retouched and characterized by a fine angle, a biplane section and a slightly convex delineation. In a techno-functional perspective, these large flakes clearly overlap the definition of the cleavers. This collection from the Observatoire Cave, which precedes 230 000 BP, also includes a series of cobbles (n=159) and one single handaxe. This lithic assemblage finds no regional equivalent, but comparisons can be made with some Acheulean large flake Industries from Spain and Northern Africa, characterized by a production of entames and the shaping of proto-cleavers (or type 0). The soucoupes of the Observatoire Cave encourage us to develop further on the peculiarities of this macrolithic technology and on their signification in a regional and Mediterranean context. Our study finally challenges the hypothesis of diffusion and consider the scenario of a local invention as plausible, within a framework of a technology that was closely adapted to the nature of the raw material

Poisson ratio and bulk lattice constant of (Sr 0.25 La 0.75 )CrO 3 from strained epitaxial thin films

International audienceAbout 30 nm thick (001)-oriented (Sr0.25La0.75)CrO3 (SLCO) epitaxial thin films were grown by solid-source oxide molecular beam epitaxy on four different single-crystalline cubic or pseudo-cubic (001)-oriented oxide substrates: LaAlO3, (LaAlO3)0.3(Sr2AlTaO6)0.7, SrTiO3 and DyScO3, which result in lattice mismatch ranging from-2% to +1.7%. All the films are of high-quality, flat and strained by the substrates. By assessing the evolution of the out-of-plane lattice parameter as a function of the in-plane lattice parameter of the samples, we determine both the Poisson ratio (ν = 0.32) and the bulk lattice constant (ab = 3.876 Å) of SLCO. The Poisson ratio significantly differs from LaCrO3 (ν = 0.23) and the (SrxLa1-x)CrO3 solid solution appears to obey structural Vegard's law. Since SLCO is the only one p-type transparent conductive oxide of perovskite structure and has promising thermoelectric properties, integrating SLCO in heterostructures and devices is therefore of paramount importance, which confers on our results their strong interest. Besides, the method used here can be straightforwardly applied to other complex oxides

Diabetes Obes Metab

AIM: Sodium-glucose cotransporter-2 inhibitors (SGLT-2i) have been commercialized in France for type 2 diabetes since April 2020 and later for heart and renal diseases. Given the recent developments in treating diabetes and the widening of SGLT-2i indications, we aimed to study changes in the use of glucose-lowering drugs in France and to characterize SGLT-2i new users. METHODS: We performed a nationwide utilization study using the French health insurance database. Trends in incidence and prevalence of glucose-lowering drug use were assessed by a repeated cross-sectional study in 2019 and 2021. A cohort study of incident SGLT-2i users was then conducted to describe patient characteristics and the strategy for treating diabetes. RESULTS: The prevalence of SGLT-2i use gradually reached 0.1% in the third quarter of 2021 and increased more significantly to 0.2% thereafter. SGLT-2i became the second most prescribed glucose-lowering drug class after metformin at the end of 2021 (0.1%). Among the cohort of 125 387 SGLT-2i new users (mean age 65.0 years; 60.1% of men), 87.6% presented a diabetic comorbidity. The patient profile changed over the study period with an increasing proportion of patients with cardiovascular (28.7% in 2020 vs. 40.2% in 2021) or renal (7.7% in 2020 vs. 11.8% in 2021) comorbidities at initiation. The main combinations used at SGLT-2i initiation were metformin (12.5%) and metformin plus dipeptidyl peptidase-4 inhibitors (8.1%). One-year probability of SGLT-2i persistence was estimated to be 55%. CONCLUSION: The expansion of indications for SGLT-2i and the broadening of the target population make it essential to assess the reasons for discontinuation and review their safety profile

Giant tuning of electronic and thermoelectric properties by epitaxial strain in p-type Sr-doped LaCrO3 transparent thin films

The impact of epitaxial strain on the structural, electronic, and thermoelectric properties of p-type transparent Sr-doped LaCrO3 thin films has been investigated. For this purpose, high-quality fully-strained La0.75Sr0.25CrO3 (LSCO) epitaxial thin films were grown by molecular beam epitaxy on three different (pseudo)cubic (001)-oriented perovskite-oxide substrates: LaAlO3, (LaAlO3)0.3(Sr2AlTaO6)0.7, and DyScO3. The lattice mismatch between the LSCO films and the substrates induces in-plane strain ranging from -2.06% (compressive) to +1.75% (tensile). The electric conductivity can be controlled over two orders of magnitude, σ ranging from ~0.5 S cm-1 (tensile strain) to 35 S cm-1 (compressive strain). Consistently, the Seebeck coefficient S can be finely tuned by a factor of almost two from ~127 μV K-1 (compressive strain) to 208 μV K-1 (tensile strain). Interestingly, we show that the thermoelectric power factor (PF = S2 σ) can consequently be tuned by almost two orders of magnitude. The compressive strain yields a remarkable enhancement by a factor of three for 2% compressive strain with respect to almost relaxed films. These results demonstrate that epitaxial strain is a powerful lever to control the electric properties of LSCO and enhance its thermoelectric properties, which is of high interest for various devices and key applications such as thermal energy harvesters, coolers, transparent conductors, photo-catalyzers and spintronic memories.Financial support from the European Commission through the project TIPS (H2020-ICT-02-2014-1-644453), the French national research agency (ANR) through the projects MITO (ANR-17-CE05-0018), LILIT (ANR-16-CE24-0022), DIAMWAFEL (ANR-15-CE08-0034-02), the CNRS through the MITI interdisciplinary programs (project NOTE), IDEX Lyon-St-Etienne through the project IPPON, the Spanish Ministerio de Ciencia e Innovación, through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV2015-0496) and the MAT2017-85232-R (AEI/FEDER, EU), PID2019-107727RB-I00 (AEI/FEDER, EU), and from Generalitat de Catalunya (2017 SGR 1377) is acknowledged. The China Scholarship Council (CSC) is acknowledged for the grant of Dong Han. Ignasi Fina acknowledges Ramón y Cajal contract RYC-2017-22531. Seebeck measurements at ILM were made within the ILMTech transport platform. The authors are also grateful to Jean-Baptiste Goure, Philippe Regreny, Aziz Benamrouche, and Bernat Bozzo for their technical support and the reviewers for their valuable and constructive comments that have improved the quality of the manuscript.Peer reviewe

CTX-M β-Lactamases in Escherichia coli from Community-acquired Urinary Tract Infections, Cambodia

The prevalence of CTX-M β-lactamases has reached a critical level, which highlights the need for study of their spread in developing countries