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Exact Minimum Cuts in Hypergraphs at Scale
No full textInternational audienceThe hypergraph minimum cut problem aims to partition the vertices of a hypergraph into two non-empty parts while minimizing the total weight of hyperedges crossing the cut. This problem lies at the core of many tasks in network reliability, VLSI placement, and community detection. We introduce HeiCut, the first algorithm that makes exact minimum cut computation feasible for both weighted and unweighted instances at scales of hundreds of millions of vertices. HeiCut presents seven exact reduction rules that provably preserve the minimum cut, and an optional heuristic contraction based on label propagation that shrinks complex and persistent structures. When no further reductions are possible, the remaining in stance is solved exactly with a known algorithm. Our extensive evaluation on more than 500 real-world hypergraphs reveals that the exact reductions alone already expose the minimum cut (i.e., the residual collapses to a single vertex or has no hyperedges) in over 85% of instances. Across all instances, HeiCut solves over twice as many instances as the state-of-the-art within set computational limits, and is up to five orders of magnitude faster. Thus, HeiCut significantly advances hyper graph minimum cut computation in real-world, large-scale scenarios
Les économistes libéraux français et l'amélioration du sort des ouvriers (1870-1914)
No full textInternational audienceThis article examines how French liberal economists addressed the issue of improving workers’ conditions between 1870 and 1914. Drawing on contributions from authors who participated in the debates of the Société d’économie politique and published in the Journal des économistes, it highlights the diversity of positions within the liberal camp, thereby challenging the idea of a homogeneous liberal doctrine. While some, such as Guyot and Passy, rejected any intervention, a first group of economists, represented by Molinari and Royer, sought to improve the functioning of the labour market by enhancing information flows and worker mobility. A second group, illustrated by Colson and Cheysson, accepted limited state intervention, particularly in the form of assistance to the poorest in exchange for work, and the implementation of social insurance system.Cet article examine comment les économistes libéraux français ont abordé la question de l’amélioration du sort des ouvriers entre 1870 et 1914. En s’appuyant sur les contributions d’auteurs ayant participé aux débats de la Société d’économie politique et ayant publié dans le Journal des économistes, il met en lumière la diversité des positions en présence, remettant ainsi en cause l’idée d’un libéralisme homogène. Alors que certains, comme Guyot ou Passy, rejettent toute intervention, une première série d’économistes, représentée par Molinari ou Royer, proposent d’améliorer le fonctionnement du marché du travail en facilitant la circulation de l’information et la mobilité des ouvriers. Une seconde série, illustrée par les développements de Colson et Cheysson, admet une intervention de l’État limitée, notamment sous la forme d’une assistance accordée aux plus démunis en échange d’un travail et de la mise en place d’un système d’assurances sociales
Community challenge towards consensus on characterization of biological tissue: C4Bio’s first findings
No full textInternational audienceThis study investigates methodological variability across various expert laboratories worldwide, with regards to characterizing the mechanical properties of biological tissues. Two testing rounds were conducted on the specific use case of uniaxial tensile testing of porcine aorta. In the first round, 24 labs were invited to apply their established methods to assess inter-laboratory variability. This revealed significant methodological diversity and associated variability in the stress–stretch results, underscoring the necessity for a standardized approach. In the second round, a consensus protocol was collaboratively developed and adopted by 19 labs in an attempt to minimize variability. This involved standardized sample preparation and uniformity in testing protocol, including the use of a common cutting and thickness measurement tool. Despite protocol harmonization, significant variability persisted across labs, which could not be solely attributed to inherent biological differences in tissue samples. These results illustrate the challenges in unifying testing methods across different research settings, underlining the necessity for further refinement of testing practices. Enhancing consistency in biomechanical experiments is pivotal when comparing results across studies, as well as when using the resulting material properties for in silico simulations in medical research
Evaluation of global biotic resource consumption against absolute boundaries
No full textInternational audienceHuman activities rely on biotic natural resources to provide products and services necessary to meet human needs. This instrumental value is captured in life-cycle assessment through the “Natural resources” Area of Protection. Although several absolute boundaries have been proposed to safeguard biotic resources, it remains unclear whether these resources are currently used at a sustainable rate. This study addresses this question by evaluating global biotic resource consumption from 1995 to 2011 against suggested biotic resource boundaries, relying on Exiobase projections to assess the evolution beyond 2011. The assessment couples absolute boundaries with life-cycle impact assessment (LCIA) methods, enabling evaluation using consistent LCIA metrics. Five absolute boundaries and four LCIA methods were adapted to the Exiobase multiregional input-output model. Results show that most of existing boundaries are already transgressed, regardless of whether mass-based or LCIA-based control variables are applied. The wide range and normative nature of existing boundaries emphasize the need for harmonized, science-based boundaries to ensure the sustainable use of biotic resources
Metallic trace elements in wild and farmed fish from the Aveiro Region (Portugal)
No full textInternational audienceThis study assessed the concentrations of 11 metallic trace elements (MTEs: As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, Zn) in fish muscle from eight wild and farmed species collected in the Aveiro region of Portugal, an area historically affected by industrial pollution. A total of 66 samples were analyzed by ICP-MS. Mean concentrations (mg/kg ww), arranged in ascending order, were: Ni (0.0001), Cd (0.0015), Co (0.0020), Pb (0.0023), Cr (0.0179), Mn (0.0862), Cu (0.2500), Se (0.2964), Fe (1.9236), As (1.9260, total As), and Zn (3.3701). Significant differences were observed among species and between wild and farmed fish, particularly in Dicentrarchus labrax and Sparus aurata. Although Cd and Pb concentrations remained below current European maximum levels, risk assessment based on safe consumption limits (SCLnc) identified total Se, Cd, and Pb as the most restrictive elements for daily intake, especially in children. For arsenic, only total concentrations were considered, as inorganic As could not be distinguished in this study. No significant non-carcinogenic risks were identified at current national average fish consumption levels; however, the potential cumulative and synergistic effects of multiple metals in chronic exposure warrant further investigation. The Metal Pollution Index (MPI < 1 for all samples) confirmed low overall contamination. These findings underscore the importance of ongoing monitoring of trace elements in fish to ensure food safety and protect vulnerable populations
Smart zwitterionic biodegradable hydrogel for sustained peptide delivery: Application to the neurotherapeutic peptide NX210c
No full textInternational audienceTherapeutic peptides offer a promising balance between specificity, safety, and bioavailability. However, their clinical use is limited by poor in vivo stability and short half-life, requiring frequent administrations that can compromise patient compliance and therapeutic outcomes. NX210c, a synthetic cyclic dodecapeptide derived from the thrombospondin repeat motif of the sub-commissural organ-spondin shows neuroprotective effects, making it a promising candidate for the treatment of neurological disorders. However, its short half-life (~15 min) requires intravenous infusion highlighting the interest of an alternative delivery method to improve the quality of life for patients.This study, report the preclinical development of an injectable, biodegradable chitosan-based hydrogel functionalized with the macrocyclic ligand DOTAGA, designed for the sustained subcutaneous release of NX210c. The hydrogel forms in situ under physiological conditions, via electrostatic and hydrogen bonding interactions. The solvent-free formulation is simple and clinically compatible. Hydrogel candidate were screened in vitro for injectability, gelation, peptide loading, and release kinetics. In vivo validation on rodents confirmed subcutaneous injectability, gelation ability, biocompatibility and biodegradability within few weeks. Pharmacokinetics studies demonstrated distinct profiles: intravenous injection led to peptide clearance within 1 h; free NX210c administered subcutaneously slightly prolonged its presence in the bloodstream, with complete elimination observed within approximately 3 h. The use of hydrogel, enables AUCs dozens of times higher, with peptide levels sustained for over 10 to 15 days. These results highlight the hydrogel's potential as a patient-friendly, clinically translatable platform for therapeutic peptides requiring sustained release. Future studies will focus on the evaluation of its therapeutic efficiency.</div
production in pp collisions at TeV
No full textInternational audienceThe measurement of production in pp collisions at TeV is presented. The measurement is performed at midrapidity in both minimum-bias and high-multiplicity pp collisions at TeV. The is reconstructed via its weak-decay topology in the decay channel with . In a novel approach, the neutral pion is reconstructed by combining photons that convert in the detector material with photons measured in the calorimeters. The transverse-momentum () distributions of the and its rapidity densities ddy in both event classes are reported. The spectrum in minimum-bias collisions is compared to QCD-inspired event generators. The ratio of to previously measured baryons is in good agreement with calculations from the Statistical Hadronization Model. The high efficiency and purity of the novel reconstruction method for presented here will enable future studies of the interaction of with protons in the context of femtoscopic measurements, which could be crucial for understanding the equation of state of neutron stars
Overexpression of the maize 9-lipoxygenase gene ZmLOX4 confers resistance to Fusarium verticillioides via the oxylipin and jasmonic acid-mediated pathways
No full textInternational audienceFusarium verticillioides is a prominent pathogen in cereals that reduces crop yields and poses a threat to food safety by producing the secondary metabolites fumonisins. Maize lipoxygenases (ZmLOXs) genes are involved in the biosynthesis of oxylipins that function as signals in regulating defense. Previously, we showed that ZmLOX4 gene mutagenesis was associated with susceptibility to F. verticillioides in kernels, seedlings and ears altering ZmLOX transcript profiles as well as LOX enzymatic activity. In the current study, we show that ZmLOX4 overexpression results in enhanced pathogen and fumonisin contamination resistance, substantiating its role in defense and making ZmLOX4 a good target to confer disease resistance. Transcriptomic and lipidomic analyses reveal that ZmLOX4 overexpression up-regulates 9-LOX gene expression and boosts the 9-oxylipin production under fungal infection. The increased expression of jasmonic acid-related genes is also observed, but is reinforced when ZmLOX4 is overexpressed, correlating with wider accumulation of jasmonic acid-related metabolites. The ZmLOX4 gene has potential applications in engineering cropping plants to increase immunity to F. verticillioides
Consolidation of virtual machines to reduce energy consumption of data centers by using ballooning, sharing and swapping mechanisms
No full textInternational audienceData centers have major environmental impacts due to their energy consumption and the manufacturing of equipment. They emit greenhouse gases and consume energy and resources, such as rare earth and water. Efficient computing resource management is therefore a key challenge for Cloud service providers today as they need to meet a growing demand while limiting the oversizing of their infrastructures. Mechanisms derived from virtualization, such as Virtual Machines (VMs) consolidation, are used to optimize resource management and infrastructure sizing, but economic and technical constraints can hinder their adoption. They require prior infrastructure knowledge and usage study to evaluate their potential, involve complex placement algorithms, and are sometimes difficult to implement in hypervisors. In this paper, we propose ORCA (OuR Consolidation Algorithm), a complete consolidation methodology designed to facilitate the production implementation of such mechanisms. This methodology includes the study of VM usage, the use of prediction models, and a VM placement algorithm that takes advantage of resource oversubscription. The choice of relevant oversubscription ratios is also addressed, with a focus on memory overcommitment through the study of memory overcommitment mechanisms:ballooning, page sharing, and swapping. Results from a detailed simulation process and deployment on a production infrastructure are presented. The methodology is tested in simulation on two production infrastructure datasets, with power consumption reduction as high as 29.8% and without consolidation error. The production deployment using VMWare vSphere and considering fault tolerance requirements reduces the energy consumption by 6.12% without causing any performance degradation