FLASH-RL: Federated Learning Addressing System and Static Heterogeneity using Reinforcement Learning

Federated Learning (FL) has emerged as a promising Machine Learning paradigm, enabling multiple users to collaboratively train a shared model while preserving their local data. To minimize computing and communication costs associated with parameter transfer, it is common practice in FL to select a subset of clients in each training round. This selection must consider both system and static heterogeneity. Therefore, we propose FLASH-RL, a framework that utilizes Double Deep QLearning (DDQL) to address both system and static heterogeneity in FL. FLASH-RL introduces a new reputation-based utility function to evaluate client contributions based on their current and past performances. Additionally, an adapted DDQL algorithm is proposed to expedite the learning process. Experimental results on MNIST and CIFAR-10 datasets have shown FLASH-RL's effectiveness in achieving a balanced trade-off between model performance and end-to-end latency against existing solutions. Indeed, FLASH-RL reduces latency by up to 24.83% compared to FedAVG and 24.67% compared to FAVOR. It also reduces the training rounds by up to 60.44% compared to FedAVG and +76% compared to FAVOR. In fall detection using the MobiAct dataset, FLASH-RL outperforms FedAVG by up to 2.82% in model's performance and reduces latency by up to 34.75%. Additionally, FLASH-RL achieves the target performance faster, with up to a 45.32% reduction in training rounds compared to FedAVG.Comment: Accepted in the 41st IEEE International Conference on Computer Design (ICCD 2023

UTILISATION D’INDICES POUR L’EVALUATION DE LA QUALITE DES SEDIMENTS : CAS DU BASSIN BOUMERZOUG (ALGERIE)

The objectives of this study are to use different indexes to assess the current pollution status in Boumerzoug basin. Indexes used in this study were Geo-accumulation Index (Igeo), Contamination Factor (CF), Contamination Degree (CD) and Sediment Pollution Index (SPI). Before, sediment trace metal concentrations (cadmium, chromium, copper, lead, nickel, zinc) have been investigated on surface sediments from permanent wadis of Boumerzoug basin in different seasons (winter, spring, summer and autumn). Trace metal concentrations followed the order: Zn>Pb>Cr>Cu>Ni>Cd. Indexes used give several status of sediment quality. Igeo, CF, CD and SPI reveal a polymetallic contamination dominated by two or more elements in which Cd, Cu and Pb are of greatest concern. Igeo gives more precision than CF, because it is classified into six classes. SPI has an advantage over the earlier indexes and viewed as a simple summary of the state of the sediment. However, the trace metal assessment indices are not to be used as the only indicator for sediment quality. More detailed analysis such as biological testing and analysis of existing benthic community related to sediment contamination should be performed for a better understanding about the nature, the fate and the toxic effects of contaminants in this ecosystem

The relationship between substructure in 2D X-ray surface brightness images and weak lensing mass maps of galaxy clusters: A simulation study

In this paper, we undertake a study to determine what insight can be reliably gleaned from the comparison of the X-ray and the weak lensing mass maps of galaxy clusters. We do this by investigating the 2D substructure within three high-resolution cosmological simulations of galaxy clusters. Our main results focus on non-radiative gas dynamics, but we also consider the effects of radiative cooling at high redshift. For our analysis, we use a novel approach, based on unsharp-masking, to identify substructures in 2D surface mass density and X-ray surface brightness maps. At full resolution (~ 15 h^-1 kpc), this technique is capable of identifying almost all self-bound dark matter subhaloes with M>10^12 h^-1 M_sun. We also report a correlation between the mass of a subhalo and the area of its corresponding 2D detection; such a correlation, once calibrated, could provide a useful estimator for substructure mass. Comparing our 2D mass and X-ray substructures, we find a surprising number of cases where the matching fails: around one third of galaxy-sized substructures have no X-ray counterpart. Some interesting cases are also found at larger masses, in particular the cores of merging clusters where the situation can be complex. Finally, we degrade our mass maps to what is currently achievable with weak-lensing observations (~100 h^-1 kpc at z=0.2). While the completeness mass limit increases by around an order of magnitude, a mass-area correlation remains. Our paper clearly demonstrates that the next generation of lensing surveys should start to reveal a wealth of information on cluster substructure. (Abridged)Comment: 30 pages, 27 figures, 3 tables. Accepted for publication in MNRAS. High resolution version available at http://www.physics.ox.ac.uk/users/powell/clustersubs_highres.pd

Optimization of Conventional Extraction Parameters for Recovering Phenolic Compounds from Potato (Solanum tuberosum L.) Peels and Their Application as an Antioxidant in Yogurt Formulation.

The aim of this work was to optimize the conventional parameters for the extraction of phenolic compounds from potato (Solanum tuberosum L.) peels (PP). A central composite design (CCD) was used to establish the impacts of ethanol concentration (%), extraction time (min), and liquid/solid ratio (mL/g). The optimal experimental conditions that maximized extraction were ethanol at a concentration of 80% (v/v) for a time of 150 min with a ratio of 1 g/30 mL. Under optimal conditions, the total phenolic content (TPC) and the total flavonoid content (TFC) were 204.41 ± 8.64 mg GAE/100 g DW and 21.47 ± 0.76 mg QE/100 g DW, respectively. The PP extract had a potent antioxidant capacity tested by phosphomolybdate and DPPH assays with IC50 of 10.65 ± 0.21 and 179.75 ± 3.18 µg/mL, respectively. Furthermore, by fortifying yogurt with PP as a natural ingredient, an improvement ofits physical, nutritional, antioxidant, and sensorial qualities was attempted in this study. The yogurts formulated with PP revealed significantly higher (p ≤ 0.05) TPC, TFC, and antioxidant capacity in comparison with the control sample. In addition, the sensory evaluation showed that the yogurts enriched with PP were preferred over the control yogurt. The results indicate that PP can be considered an interesting byproduct since it can improve the nutritional, bioactive, and sensorial profile of yogurt, highlighting that PP, due to its high phenol content, can substantially improve the antioxidant effect of the new formulated yogurt

Évaluation du niveau de contamination par les éléments traces métalliques (cadmium, cuivre, nickel et zinc) des sédiments de l’oued Boumerzoug et ses affluents, et leur transfert vers la chénopodiacée spinacia oleracea (L.)

L’objectif de la présente étude est d’évaluer la distribution de quatre éléments traces métalliques (ETM), cadmium, cuivre, nickel et zinc, dans les différentes parties anatomiques (racines et feuilles) d’une chénopodiacée Spinacia oleracea (L.), en lien avec le niveau de contamination des sédiments où elle pousse, de l’oued Boumerzoug et ses affluents. Localisé dans le Constantinois au nord-est de l’Algérie, l’oued draine un bassin versant de 1 832 km2 avec ses zones urbaines et industrielles. Cette étude inclut 14 stations, 5 situées sur l’oued Boumerzoug et 9 sur ses affluents, sélectionnées en des lieux stratégiques et échantillonnées cinq fois au mois de mai, septembre et décembre 2016, ainsi qu’en mars et juillet 2017. Les teneurs moyennes des ETM des sédiments sont de 0,44 ± 0,30 mg∙kg-1 (masse sèche) pour Cd, 43,61 ± 36,45 mg∙kg-1 (ms) pour Cu, 35,16 ± 9,85 mg∙kg-1 (ms) pour Ni et 181,33 ± 115,12 mg∙kg-1 (ms) pour Zn. Le transfert des ETM a été étudié chez l’épinard S. oleracea dont les différentes parties accumulent différemment les métaux. Les concentrations des ETM dans les sédiments et la chénopodiacée sont très variables aussi bien dans l’espace que dans le temps. Nos résultats montrent que la chénopodiacée séquestre dans ses racines le Cd, le Cu et le Ni, alors que le Zn est transloqué vers les feuilles. La hiérarchie des teneurs moyennes en métaux dans les épinards (Zn > Cu > Ni > Cd) est similaire à celle des sédiments.The aim of this study is to assess the distribution of four trace metals (TM): cadmium, copper, nickel and zinc in roots and leaves of a Chenopodiaceae Spinacia oleracea (L.) in relation to the contamination level of the sediments of the Boumerzoug wadi and its tributaries. Located in the Constantinois in Northeast Algeria, the wadi drains a watershed of 1 832 km2 with its urban and industrial areas. A total of 14 stations, 5 in Boumerzoug wadi and 9 in its tributaries, were selected in strategic points and sampled at five occasions in May, September, and December 2016, as well as in March and July 2017. The mean TM levels in the sediments are 0.44 ± 0.30 mg∙kg-1 (dry weight) for Cd, 43.61 ± 36.45 mg∙kg-1 (dw) for Cu, 35.16 ± 9.85 mg∙kg-1 (dw) for Ni and 181.33 ± 115.1 mg∙kg-1 (dw) for Zn. The transfer of trace metals was studied in spinach. The different parts of S. oleracea accumulate trace metals differently. Trace metals concentrations in the sediments and the chenopodiaceae are highly variable both spatially and temporally. Our results indicate that S. oleracea cοncentrates and sequesters Cd, Cu, and Ni in its roots, whereas Zn is translocated to leaves. The hierarchy of mean TM level in spinach (Zn > Cu > Ni > Cd) is similar to that of sediments

Effet thérapeutique de l’extrait aqueux de Globularia alypum suite à une insulinotoxicité induite in vitro sur les cardiomyocytes de Rattus norvegicus. [Therapeutic effect of aqueous extract of Globularia alypum following in vitro insulin induced toxicity on Rattus norvegicus cardiomyocytes]

Introduction. L’insulino‐résistance, marquée par une réaction inflammatoire via la production de TNF‐α et par l’hyperinsulinémie compensatoire, conduit à long terme à l’installation d’une glucolipotoxicité et du diabète de type 2. Objectif. Dans cette étude, les effets d’un extrait aqueux de Globularia alypum (Ga) a été analysé in vitro, suite à un stress induit sur le cardiomyocyte de Rattus norvegicus. Matériel et Méthodes. Le stress a été induit par addition d’une dose élevée d’insuline (10 UI/ mL). Les taux de prolifération ont été déterminés par comptage et les contenus cellulaires en monoxyde d’azote (NO), en malondialdéhyde (MDA) et en catalase ont été évalués. Résultats. En présence de la dose élevée d’insuline, les cardiomyocytes ont montré une diminution de la survie cellulaire, un déséquilibre du statut redox en faveur d’une augmentation de NO et de MDA et d’une diminution d’une enzyme du système antioxydant, la catalase. Suite à l’action de l’extrait de Ga, il a été noté une amélioration du taux de prolifération cellulaire, une diminution du taux de No et de MDA ainsi qu’une augmentation de l’activité de la catalase. Conclusion. L’état de stress induit sur le cardiomyocyte par l’insulino‐résistance, mimé par la dose élevée d’insuline, entraîne des altérations physiologiques et biochimiques. Ces dernières, précurseurs de mort cellulaire par apoptose sont atténuées après addition d’un extrait de Globularia alypum, lequel pourrait constituer une cible thérapeutique en aval de l’installation du DT2

Glucotoxicity Induced Oxidative Stress and Inflammation In Vivo

Context. Brassica rapa is considered as natural source of antioxidants and is used to treat diabetes. Objective. Our study carried the impact of glucotoxicity induced in vivo and in vitro in vascular smooth muscle cells (VSMCs) in Psammomys and the therapeutic effect of Brassica rapa (AEBr). Materials and Methods. We administered a hyperglucidic diet (30% sucrose) for 9 months and a treatment for 20 days with AEBr at 100 mg/kg. VSMCs were submitted to D-Glucose (0.6%) for 48 hours and treated with AEBr (2100 μg/mL) for 24 hours. We measured, in blood metabolic parameters, the redox statues and inflammatory markers in adipose tissue. Histological study was effectuated in liver. In VSMCs, we measured markers of glucotoxicity (IRS1p Serine, AKT) inflammation (NO, MCP1, TNFα, and NF-κB) and oxidative stress (oxidants and antioxydants markers). Cell viability and apoptosis were estimated by the morphological study. Results. AEBr corrects the metabolic parameters and inflammatory and oxidative markers in blood and homogenate tissue and reduces lipid droplets in liver. It induces, in VSMCs, a significant decrease of IRS1p serine, cyt c, NO, MCP1, TNFα, NF-κB, protein, and lipid oxidation and increases cell viability, AKT, ERK1/2, catalase, and SOD activity. Conclusion. Brassica enhanced the antidiabetic, anti-inflammatory, and antioxidant defense leading to the protection of cardiovascular diseases

Assessment of freshwater sediment quality: potential ecological risk and ecotoxicity tests as complementary approaches

International audienceThe main objective of this study was to assess the quality of sediments collected from rivers in the Northeast of Algeria. A dual approach, including trace metals assessment as well as ecotoxicity tests (Microtox(R) solid and leachate phase assays), was conducted. Results showed that surface sediments were contaminated with Cd, Cu, Pb and Zn. By using sediment quality guidelines (SQGs) and potential risk index, we concluded that there was a significant potential risk for benthic fauna. Microtox(R) solid and leachate phase assays showed that sediments with the highest trace metal contents appear to be potentially ecotoxic for Allivibrio fisheri. In this study, in attempting to link chemical characteristics with ecotoxicity test results, we got a trend going in the right direction. Samples with highest metal contents appear to be potentially ecotoxic for A. fisheri. These results suggest the usefulness of a diversity of approaches in sediment quality assessment