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“No land’s land? ” Squatting informality and governing the ungoverned in Beirut’s southern peripheries
No full textInternational audienceIn a neighborhood where property titles are as absent as garbage collection and stormwater drains, squatting isn't resistance—it’s the default condition of urban life. This communication examines Hay el Sellom, an informal settlement on the southern edge of Beirut, where occupation is not a political choice but a socio-urban outcome of decades of systemic neglect. Built on squatted agricultural land since the 1970s, the district embodies a striking paradox: a vacuum of state services coexists with dense informal governance by politico-sectarian networks. Institutions are largely absent—except during elections. In the meantime, the garbage piles up, the floodwaters rise, and residents adapt. And adapt. And adapt again.Drawing on ethnographic fieldwork conducted between 2021 and 2024—including semi-structured interviews, transect walks, participatory mapping, and direct observation—this communication explores how residents navigate chronic flood risk in a context where legal status, infrastructure, and authority are all in flux. These “squatters” may not claim political intent, but their daily improvisations—homemade drains, ad-hoc sandbag systems, negotiated access to aid—constitute micro-political acts that shape space, survival, and power.Rather than distinguish “squats of necessity” from “political squats,” I argue for recognizing the infrapolitical practices (Scott, 1985; Simone, 2008) that structure everyday life in such environments. In Hay el Sellom, agency is not heroic, but partial, situated, and tactical. It both sustains informality and unsettles dominant narratives of urban order. The selective formalization of neighboring zones, often in exchange for political loyalty, further reveals how the state governs by fragmentation—tolerating or repressing occupation along sectarian and electoral lines (Fawaz, 2016; Roy, 2011).In this “unplanned city within the planned,” squatting is not a temporary act—it is a temporal strategy, sustained through continuous adaptation, negotiation, and endurance. This case invites us to rethink squatting beyond legal frameworks and militant postures. It calls for an expanded, decolonized vocabulary of urban practice—one that accounts for the blurred lines between survival and politics, and recognizes occupation not just as protest, but as the infrastructure of everyday life. And if the state won’t provide drainage, planning, or recognition, then people build their own kind of infrastructure—both material and social. It may not be legal, but it holds up better than most official plans. At least until the next flood
Modeling of Iron Isotope Fractionation During Aerosol Cloud Processing
No full textInternational audienceIron (Fe) is an essential micronutrient for the development of oceanic biomass, which is one of the main carbon sinks on a global scale. In about 30% of the oceans, the development of this biomass is constrained by an iron deficiency that limits primary production. This deficiency is related to the very low concentrations of bioaccessible Fe in the surface waters. In order to understand the origin and consequences of these low Fe levels (some ng Fe/L), various models have sought to determine the variability of Fe inputs to the ocean, particularly via aerosols. Recent progress in the measurement of Fe isotopic composition has made it possible to test the sensitivity of these models to spatiotemporal variations in inputs. However, this approach is made difficult by the existence of isotopic fractionation phenomena that would be linked to the dissolution of particles within clouds. Our previous works seem to show that this isotopic effect is linked to the existence of a competition between Fe-ligand complexes in solution and the presence of some similar complexes on the surface of particles. The FAAR project aims to explain these processes through a double approach. First, it will simulate the dissolution of Fe aerosol-like particles in solutions mimicking cloud water. Changes over time in both Fe solubility and isotopic composition will be measured. Second, Fe isotopic fractionation solid-solution will be estimated via quantum chemical methods and compared, in the same way, to the respective stabilities of the surface and solution complexes, in order to conclude on the possibility of extending our simulations to more realistic atmospheric conditions. For this purpose, hematite (α-Fe2O3) was chosen as it is one of the most abundant and thermodynamically stable iron oxide in surface soils, and it is commonly present in desert dust resuspended by storms
Climate-induced shifts in cod spawning phenology across the North Atlantic
No full textInternational audienceSpawning underpins fish stock regeneration. Here, we investigate climate effects on spawning phenology in Atlantic cod (Gadus morhua), a severely exploited species whose stocks are now also affected by climate change. For the first time, we model daily cod egg occurrences as a spawning proxy across the North Atlantic. With a concordance of 84% between our model and basin-scale observations, our results predict different climate change outcomes for western (eastern Newfoundland) and eastern (North Sea) stocks. In eastern Newfoundland where cod is at the centre of its thermal niche, a phenological shift in spawning was observed. In the warmer North Sea, such a phenological adjustment did not occur, leading to a substantial reduction in spawning. Our model explains fluctuations in the North Sea cod stock better than those in the Eastern Newfoundland stock, where unaccounted anthropogenic (overfishing) and environmental (trophodynamics) factors may have influenced cod abundance over the considered time series. Our results provide an improved understanding of how future climate change and other drivers interact in driving stock dynamics
Effect of protesting by burning barricades on PM2.5: chemical composition and oxidative potential evaluation
No full textInternational audienceProtests have become a global phenomenon, with road blockades among the most common methods used to express objection. In many countries, these blockades involve the open burning of materials such as tires, wood, and waste. In this study, PM 2.5 was collected during an active burning protest episode as well as over the subsequent days. PM 2.5 was characterized for the carbonaceous fraction, water-soluble ions, elements, and organic compounds (alkanes, polycyclic aromatic hydrocarbons (PAHs), phthalates, fatty acids, hopanes, levoglucosan, dioxins, furans, and dioxin-like polychlorobiphenyls (PCDD/Fs and DL-PCBs). The major contributors to PM 2.5 during the burning episode were elemental carbon, organic carbon, and zinc, which collectively accounted for 42% of total PM 2.5 . The chemical profile also revealed a marked increase in combustion-related compounds such as alkanes, PAHs, PCDD/Fs, and DL-PCBs, highlighting the strong influence of open burning emissions on air quality. Oxidative potential (OP) assays showed a clear increase during the burning day, with peak values of 6.6 nmol/min/m 3 for OP-DTT and 5.8 nmol/min/m 3 for OP-AA. While these OP levels were nearly double those of non-burning days, the increase was notably less pronounced compared to the sharp fluctuations observed in chemical tracers and toxic equivalents. The temporal trends also indicated differing sensitivities between the assays, with OP-DTT more closely following OC levels, while OP-AA was more influenced by EC and elemental content. These findings highlight the complex chemical nature of emissions from protest-related burning and underscore the need for non-toxic alternatives to such practices.</div
Functionalized Anti-Cryptophane-A as a Platform for Type II Porous Ionic Liquids
No full textInternational audienceType II porous ionic liquids could be prepared at room temperature by dissolving up to 5 wt% of anti-cryptophane-A derivatives functionalized with alkyl or fluorinated alkyl chains in phosphonium- and pyrrolidinium-based ionic liquids. In this study, we provide the first direct experimental evidence that these molecular cages retain their internal free volume when dissolved in ionic liquids. At 303 K and 1 bar, the porous ionic liquids prepared as solutions of anti-cryptophane-A grafted with a ten-carbon alkyl chain in the ionic liquids [P6,6,6,14][NTf2] (1:36), [P6,6,6,14][DCA] (1:52) and [C1C3pyrr][NTf2] (1:50) absorb 1 3.0, 3.5 and 11 times more methane than the pure ionic liquid, respectively. The solution of anti-cryptophane-A grafted with a fluorinated alkyl chain in [P6,6,6,14][NTf2] (1:73) absorbs in turn 1.8 times more methane than the pure ionic liquid. We show that 97(2)% of the cryptophane dissolved in [P6,6,6,14][NTf2] can encapsulate one molecule of methane, whereas only 60(1)% of the cavities in solid cryptophane are available for gas encapsulation. The presence of permanent porosity in the liquid solution is further supported by controlled atmosphere 1H NMR spectroscopy that allows to distinguish between free and caged methane thus providing molecular-level evidence that the gas is encapsulated in the free cryptophane cavities
Anytime benchmarking of forty-five PAES-25 configurations on multi- and many-objective variants of leading ones trailing zeros functions
No full textInternational audienceThe Leading Ones Trailing Zeros (LOTZ) benchmark is a well-established bi-objective pseudo-Boolean function (of scalable size) that has both a linear-sized Pareto front, and also a front that is “far away” from a random solution. As such it is a useful function for understanding the behaviour of multi-objective optimization algorithms, especially regarding their ability to approach the front and expand and maintain solutions all along it. It has contributed to both algorithm design and theoretical analysis. In this paper, we make use of three variants of LOTZ, recently introduced , which generalized it to the many-objective case in different ways while aiming to maintain similar properties of the original. We add further detail to the mathematical description of the benchmarks and use them to analyse the performance of a simple multi-objective local search algorithm (PAES-25) (based on (1+1)-PAES) with plug-in modules for archiving, neighbourhood, selection method (from the archive or not), and acceptance function. We measure the anytime performance of PAES-25 in different variants by observing a suite of online measures that give an insight into the dynamics of the algorithm and provide guidance as to choice of configuration depending on factors such as time available and size of Pareto approximation set desired . We believe that the benchmarks and the anytime, multidimensional methods used for analysis might motivate further theory (especially of many-objective optimization and archiving) and may also contribute usefully to algorithm design ideas
Fatty acid‐based deep eutectic solvents for efficient absorption of VOCs : Hydrophobicity and molecular mechanism study
No full textInternational audienceThe absorption performance of fatty acid-based deep eutectic solvents (DESs) for volatile organic compounds (VOCs) of varying hydrophobicity was investigated through a combination of experiments and molecular simulations. Partition coefficient experiments demonstrated the DES composed of tetrabutylammonium bromide (TBAB) and octanoic acid (OCA) in a molar ratio of 1:2 exhibits dual-functional absorption performance, effectively absorbing both weakly hydrophobic VOCs (e.g., dichloromethane and chloroform) and strongly hydrophobic VOCs (e.g., limonene and octamethylcyclotetrasiloxane). Fatty acid-based DESs retained both absorption performance and structural stability in five absorption-desorption cycles. Both VOC and solvent hydrophobicity are likely to positively affect absorption performance, with higher hydrophobicity leading to stronger absorption ability. Molecular simulations uncover that VOC absorption in TBAB:OCA can be attributed to three mechanisms: (1) large free volume of TBAB:OCA, (2) electrostatic interactions between TBAB and weakly hydrophobic VOCs that promote solubilization, and (3) Van der Waals interactions between OCA and strongly hydrophobic VOC that enhance absorption
Causes volontaires (et dénominations) des paiements
No full textInternational audienceSommaire_ 1Les causes volontaires (et les dénominations) des paiements. 2Partie 1. – Les paiements pour un avantage évident. 4Chapitre 1. – Les paiements d’opérations marchandes. 4Section 1. – Le paiement d’un bien ou d’un service obtenu_ 5Section 2. – Le paiement d’actes futurs ou rétractables. 26Chapitre 2. – Les paiements d’une relation de travail 37Section 1. – Les rémunérations de la force de travail. 37Section 2. – Les sommes accessoires de la rémunération_ 54Partie 2. – Les paiements sans avantage apparent. 64Chapitre 1. – Les paiements issus d’une intention libérale_ 66Section 1. – L’intention libérale dans un contrat. 66Section 2. – La libéralité par engagement unilatéral. 75Chapitre 2. – Les redevances et frais dus à un service public 83Section 1. – Le coût d'avantages imaginés gratuits. 83Section 2. – Les frais de scolarité et de santé parfois dus 8
L’ entreprise et les vicissitudes de ses créateurs
No full textInternational audienceContenu du livreAvant-propos 5Sommaire_ 71) L’impossibilité de devenir tous des entrepreneurs. 92) Penser la performance d’entreprise comme un construit systémique : Critères d’analyse 673) Dépenses publiques et croissance économique en Algérie : approche par un modèle de contrôle optimal 1334) Pour une définition dynamique de la cessation des paiements 1635) PME privées algériennes et facteurs limitatifs de leur croissance_ 1966) La contribution des perspectives fondées sur la théorie des ressources à la compétitivité tifs des entreprises 2477) L’effet translatif consolidé de la subrogation de l’AGS dans les droits des salariés 2858) L’impact du contrôle de gestion sur la performance globale et durable des entreprises 3119) L’université et l’entrepreneuriat : nouveaux paradigmes de l’enseignement ? 32510) Renforcer la gouvernance des PME par l’audit interne : enjeux et perspectives dans le contexte algérien_ 34311) Impact du Développement financier sur la Dynamique de création des entreprises : évidence en Données de Panel sur les pays du MENA_ 395Quatrième couverture_ 435Table des matières 43
Relationship between Otolith and Fish Sizes : Validation Using Their 3D Shape Analysis
No full textInternational audienceNearly one million otoliths, the calcified structures of the inner ear in teleost fish, are sampled annually in the world for the stock assessment. The analysis of internal otolith measurements is based on the idea that there is a relationship between fish size and otolith size and that this proxy is representative of the whole shape of the otolith. In this study, the relationship between fish total length (TL) and five morphometric parameters extracted to the 3D shape otolith analysis, are examined: length (OL), width (OW), height (OH), area (OA) and volume (OV), based on a set of 104 otoliths belonging to 22 species from the English Channel and the North Sea. The otoliths were scanned in three dimensions using an X-ray microtomography, and the relationships were modelled using an allometric log-linear model. The results reveal significant relationships for all metrics (p < 0.001), with coefficients of determination (R 2 ) ranging from 0.500 to 0.656. In the multi-species pooled model, otolith width (R 2 = 0.656) proved to be the most robust predictor of fish size, slightly outperforming 3D metrics such as area (R 2 = 0.617) and volume (R 2 = 0.580). Otolith length (R 2 = 0.556) was less accurate than three-dimensional metrics. But given the limited sample sizes per species, these allometric trends should be viewed as preliminary, necessitating larger datasets for species-specific validation. The usual morphometric parameters, such as otolith length, are significant proxies of the whole shape of the otolith. These results suggested the common idea that otolith length is a useful indicator, but otolith width must be considered for greater accuracy and 3D metrics for more detailed shape information. However, the combination of species with varying ecologies and growth rates influences data dispersion and highlights the need for speciesspecific calibrations. These findings confirm the relevance of otolith metrics for estimating fish size and strengthen their utility in trophic ecology, paleoecology, and fisheries management studies