Divergent IR gluon propagator from Ward-Slavnov-Taylor identities?

We exploit the Ward-Slavnov-Taylor identity relating the 3-gluons to the ghost-gluon vertices to conclude either that the ghost dressing function is finite and non vanishing at zero momentum while the gluon propagator diverges (although it may do so weakly enough not to be in contradiction with current lattice data) or that the 3-gluons vertex is non-regular when one momentum goes to zero. We stress that those results should be kept in mind when one studies the Infrared properties of the ghost and gluon propagators, for example by means of Dyson-Schwinger equations.Comment: 6 pages, bibte

Non-perturbative Power Corrections to Ghost and Gluon Propagators

We study the dominant non-perturbative power corrections to the ghost and gluon propagators in Landau gauge pure Yang-Mills theory using OPE and lattice simulations. The leading order Wilson coefficients are proven to be the same for both propagators. The ratio of the ghost and gluon propagators is thus free from this dominant power correction. Indeed, a purely perturbative fit of this ratio gives smaller value ($\simeq 270$MeV) of \Lambda_{\ms} than the one obtained from the propagators separately($\simeq 320$MeV). This argues in favour of significant non-perturbative $\sim 1/q^2$ power corrections in the ghost and gluon propagators. We check the self-consistency of the method.Comment: 14 pages, 4 figures; replaced with revised version, to appear in JHE

The strong coupling constant at small momentum as an instanton detector

We present a study of $\alpha_{MOM}(p)$ at small p computed from the lattice. It shows a dramatic $\propto p^4$ law which can be understood within an instanton liquid model. In this framework the prefactor gives a direct measure of the instanton density in thermalised configurations. A preliminary result for this density is 5.27(4) fm^{-4}.Comment: 12 pages, 4 figure

Preliminary Calculation of αs\alpha_s from Green Functions with Dynamical Quarks

We present preliminary results on the computation of the QCD running coupling constant in the $\widetilde{MOM}$ scheme and Landau gauge with two flavours of dynamical Wilson quarks. Gluon momenta range up to about 7 GeV ($\beta =$ 5.6, 5.8 and 6.0) with a constant dynamical-quark mass. This range already allows to exhibit some evidence for a sizable $1/\mu^2$ correction to the asymptotic behaviour, as in the quenched approximation, although a fit without power corrections is still possible with a reasonable $\chi^2$. Following the conclusions of our quenched study, we take into account $1/\mu^2$ correction to the asymptotic behaviour. We find $\Lambda_{\rm \bar{MS}}^{N_f=2} = 264(27) {\rm MeV} \times [{a^{-1}(5.6,0.1560)}/{2.19 {\rm GeV}}]$, which leads to $\alpha_s(M_Z) = 0.113(3)(4)$. The latter result has to be taken as a preliminary indication rather than a real prediction in view of the systematic errors still to be controlled. Still, being two sigmas below the experimental result makes it very encouraging.Comment: 14 pages, 3 figs., 2 tabs., revte

Intraspecific Competition in Lucerne and Relationships with Reserve Availability

Below-ground reserves are thought to provide an indication of a forage potential for shoot regrowth after defoliation. The aim of this work was to re-evaluate the causal relationships existing between organic reserves (non-structural carbohydrates and N reserves) and shoot regrowth of alfalfa. The variations brought about by cultivar differences (cv Lodi or Europe), length of the previous regrowth period (30 or 45 d), or by intraspecific competition for light within a dense canopy, were studied. Field grown plants were harvested at weekly intervals, and separated as dominant, intermediate and suppressed plants. Shoot regrowth yield was determined and taproot were analyzed for starch, N, soluble proteins and vegetative storage proteins. Results showed that taproot starch and N contents were modified by the length of the previous regrowth but not by the position of the plant within the canopy. Soluble protein or VSP concentrations increased with the length of the previous regrowth, and with a higher position of the plant within the canopy. Shoot regrowth yield was linearly related to taproot soluble protein and VSP contents on day of defoliation, but relationships were not found with initial starch or N contents. These results suggest that root protein and VSP are key organic nutrient for alfalfa shoot regrowth after harvest

0401: Which parameters can predict the response to exercise training in cardiac patients?

AimsBenefit effects of exercise training are well known and validated after a cardiac event, but some patients fail to ameliorate their functional capacity. This retrospective study determined which parameters in the initial cardio pulmonary exercise test could predict an improvement of functional capacity after training in cardiac patients.Methods and results292 cardiac patients with a complete training intervention were divided in two groups at the end of their rehabilitation : one group with a gain equal or more than 1 MET (148 patients) and one group with a gain less than 1 MET (144 patients) when the initial and final cardio pulmonary exercise tests were compared. The cardiac event (coronary revascularization 38%, aortic valvular surgery 23%, coronary stenting 18%) was similar in both group. The initial peak VO2 was not different (100 watts vs 110 watts, 15.6ml/kg/min vs 16.1ml/kg/min) neither the ventilator threshold nor the training intervention (19.3 sessions vs 17.9). At the end of the exercise training intervention, the gain of peak VO2 was 4.1ml/kg/min (+28%) in the global population and 6.8ml/kg/min (+46%) in the group ≥1 METS vs 1.29ml/kg/min (9.3%) in the group < 1 MET. Clinical predictor factors for a gain ≥1 MET were: age (58.3 years vs 62**p < 0,05), sex male (92% vs 83%*), ejection fraction (LVEF 52,5% vs 49,9%****p < 0,001). The initial discriminated exercise parameters were the energetic cost per watt (VO2/watt) 11,4 vs 12,2** the ventilatory cost (VE/watt) 0.62 vs 0.67*, the intensity per body kilogram (watts/kg) 1.43 vs 1.31* and the cardiac frequency per 1 liter of VO2 was lower 102 vs 110*.ConclusionThe benefit on functional capacity after exercise training intervention depended more of the initial physical condition than of the cardiac pathology in patients discharged in our cardiac rehabilitation centers. The exercise training should be more directed by the initial excise test

JMIR Res Protoc

BACKGROUND: With aging of the population, the search for alternative models of care adapted to older people with dependency is necessary. In this setting, foster families (1-3 older people per family) could be an alternative to nursing homes, residential care facilities, or community- and home-based care. OBJECTIVE: The KArukera Study of Ageing in Foster Families is a prospective cohort study designed to investigate the care pathways of older people with dependency in foster care over a year. The 1-year hospitalization rate (main objective), cost of hospitalization, incidence of mortality, prevalence of geriatric syndromes, and quality of life of residents will be assessed. Quality of life and burnout of their respective foster caregivers will also be studied. METHODS: This study cohort will include 250 older people living in foster families in Guadeloupe (French West Indies), as well as their respective foster caregivers. Both older people and caregivers will be interviewed concurrently on site at three time points: (1) at baseline, (2) at 6 months, and (3) at 12 months. For older people, we will collect anthropometric measures, cognitive impairment, depressive and anxiety symptoms, functional abilities, physical frailty, information on general health status, quality of life, and care pathways (hospitalization, mortality, and medical and paramedical consultations). We will also assess the quality of life and burnout symptoms of family caregivers at each follow-up. A phone update of vital status (alive or death) and care pathways of residents will be carried out at 3 and 9 months after the baseline examination. RESULTS: Recruitment opened in September 2020 and ended in May 2021, with 109 older people recruited and 56 respective foster caregivers. The 1-year follow-up was ended in June 2022. Data analyses are ongoing and the first results are expected to be published in May 2023. CONCLUSIONS: Foster families are a potentially innovative way to accommodate dependent older people. This study could help define the clinical profile of older people adapted to foster families in the transition from frailty to dependency. The effectiveness of foster families, in terms of hospitalizations and mortality, will be compared with other models of care, particularly nursing homes. In this setting, a twin study carried out in nursing homes in Guadeloupe with similar aims and outcomes will be conducted. Beyond mortality and morbidity, the numerous outcomes will allow us to assess the evolution of geriatric syndromes over time. TRIAL REGISTRATION: ClinicalTrials.gov NCT04545775; https://clinicaltrials.gov/ct2/show/NCT04545775. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/40604

Evaluation d’un interposer électro-optique sur substrat de verre pour interconnexions optiques 400 Gb/s à base de technologie photonique sur silicium

Data traffic inside data centers has grown exponentially in recent years, with a constant pressure storage capacity, data rate and latency. A direct consequence of this race for performance is the persistent improvement in interconnect technologies to meet this demand. In the search for higher data rate and lower cost optical fiber communications for data centers, silicon photonics, an electro-optical technology derived from standard CMOS technologies, appears as a promising solution to reduce power consumption and enhance data rates of optical links while remaining economically viable. Despite leveraging most of the developments around the CMOS platform, Silicon photonics presents additional packaging constraints related to the interfacing of input/output optical fiber. These packaging constraints induce a substantial increase of silicon photonics bases optical transceivers cost and complicates the implementation of technologies such as coarse wavelength division multiplexing (CWDM).The purpose of this thesis is to study and develop a low-cost interposer made on a glass substrate implementing both electrical and optical functions with the ambition to perform a complete passive assembly of a CWDM transceiver based on STMicroelectronics PIC25G silicon photonic technology.Firstly, this work proposes to design the interposer main components, namely, single mode waveguides, vertical coupling structures and high frequency transmission lines. Then, a fabrication process mainly relying on femtosecond laser ablation that allow to implement these components on a glass substrate as well as the assembly with an existing PIC25G chip is developed. Finally, the interposer and the complete assembly functions are demonstrated through detailed electrical, optical and hybrid characterizations.We fabricated an interposer implementing multimode waveguides with propagation losses < 6dB/cm at 1310 nm, coplanar transmission lines with insertion losses of 3 dB/cm at 60 GHz, slanted TIR mirrors and all the electrical and optical routing allowing to test the detection and modulation of light by the PIC25G chip. We achieved the assembly of the PIC25G chip over the interposer using the conventional flip-chip technique and demonstrated an optical coupling between the polymer waveguide interposer and the silicon-on-insulator waveguide of the PIC25G chip through the measurement of the photo-current of an SiGe photodiode embedded in the silicon photonic chip.Le trafic de données interne aux datacenters a connu une croissance exponentielle ces dernières années avec une mise sous pression permanente de la capacité de stockage, du débit et du temps de latence. Une conséquence directe de cette course à la performance est l'amélioration inexorable des technologies d'interconnexion pour répondre à cette demande. Dans la recherche de communications à fibre optique à faible coût pour les datacenters, la photonique sur silicium, une technologie électro-optique dérivée des technologies CMOS standard, apparaît comme une solution prometteuse pour réduire la consommation d'énergie, améliorer les débits de données des liaisons optiques tout en restant économiquement rentable. Bien que les procédés technologiques associés aux plateformes CMOS puissent être judicieusement exploités pour l'intégration monolithique de fonctions optiques extrêmement denses et performantes, la photonique sur silicium présente néanmoins des contraintes de packaging supplémentaires liées à l'interfaçage avec les fibres optiques d'entrée/sortie. Ces contraintes d'assemblage entrainent un accroissement substantiel du coût des émetteurs-récepteurs optiques à base de puces photoniques silicium et compliquent la mise en œuvre de technologies telles que le multiplexage en longueur d'onde à bas coût (CWDM).L'objectif premier de cette thèse est d'étudier et développer une version bas coût d'interposeur embarquant des fonctions électriques et optiques intégrés à un substrat de verre. L'ambition consiste à réaliser l'assemblage passif complet d'un émetteur-récepteur CWDM basé sur la technologie photonique sur silicium PIC25G de STMicroelectronics.En premier lieu, ce travail propose la conception des principales fonctions élémentaires intégrée à l'interposeur, à savoir, des guides d'ondes monomodes, des structures de couplage vertical et des lignes de transmission hautes fréquences. Dans un second temps, un procédé de fabrication, principalement basé sur l'ablation laser femtoseconde, a été développé afin d'intégrer ces fonctions sur un substrat de verre sur lequel une puce PIC25G peut être interfacées. Enfin, la fonctionnalité de l'interposeur et de l'assemblage complet a été démontrée au travers d'un travail détaillé de caractérisations électriques, optiques et mixtes.Nous avons fabriqué un interposeur intégrant des guides d'ondes multimodes avec des pertes de propagation <6 dB / cm à 1310 nm, des lignes de transmission coplanaires avec des pertes d'insertion de 3 dB / cm à 60 GHz, des miroirs de redirection du signal optique et l'ensemble du routage électrique et optique permettant de tester la détection et la modulation de la lumière par la puce PIC25G. Nous avons réalisé l'assemblage de la puce PIC25G sur l'interposeur en utilisant une technique classique de flip-chip et avons validé le couplage optique entre les guides d'ondes en polymère de l'interposeur et les guides d'ondes sur substrat silicium-sur-isolant (SOI) de la puce PIC25G grâce à la mesure du photo-courant d'une photodiode SiGe intégrée dans la puce photonique

Les polyphénols des pommes à cidre (diversité variétales et oxydation)

CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF