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Settling on their ground: The shifting land politics of armed actors in the urban margins of Medellín
No full textInternational audienceHow do armed groups shape land orders in the urban margins? While the power dynamics of non-state armed actors over land resources have been extensively studied in rural contexts, urban settings have received far less attention. In response to the growing influence of criminal organizations in the informal land markets of Latin American cities, this article offers a historical perspective on the involvement of armed actors in Medellín’s political economy of urban land. From guerrilla movements in the 1970s to contemporary criminal gangs, we trace how different groups have exercised land control in informal settlements. Building on this historical perspective, we argue that, while control over land access has long been a tool of territorialization for non-state armed actors, the contemporary criminal land market reflects a shift compared to earlier periods, as these actors seek to monopolize land control and extend their regulatory power over local populations
Le stockage en super-réfrigération réduit la croissance et la diversité des communautés bactériennes associées aux filets de saumon de l’Atlantique (Salmo salar)
No full textThe data were shared. Raw reads have been deposited in the Sequence Read Archive (SRA) under the project accession number PRJNA1233232.International audienceSuperchilling is an innovative preservation technique that maintains food products at temperatures between conventional refrigeration and freezing. It addresses the challenge of minimizing food spoilage while enhancing process sustainability. In this study, the evolution of the bacterial ecosystem of fresh salmon fillets was investigated under two superchilling temperatures (–1.8 °C and –2.8 °C) and compared with conventional refrigeration at 2 °C and storage at the initial freezing point (–0.8 °C). Total viable counts were monitored over a 20-day storage period using Plate Count Agar (PCA), and bacterial community diversity was assessed at day 0 and after 20 days of storage using 16S rRNA gene metabarcoding. Although superchilling did not fully inhibit bacterial growth, it effectively slowed microbial proliferation compared with refrigeration, thereby significantly extending microbiological shelf life. Bacterial community composition changed markedly after 20 days of cold storage, with subzero storage temperatures being more strongly associated with reduced microbial diversity. Pseudomonas became dominant under all conditions, particularly under superchilling (reaching up to 90.6%), followed by Photobacterium, which declined to the second position, and Brochothrix which was not detected at day 0. Cold temperatures strongly influenced microbial ecosystems, with superchilling promoting the development of more homogeneous communities. Overall, this study demonstrates the decisive influence of storage temperature on microbial community composition and provides a basis for selecting complementary approaches to optimize the industrial application of superchilling
Climate shocks and banking sector stability: Evidence from El Niño southern oscillation
No full textInternational audienceThis study introduces a novel ex ante approach to assess the short-term impact of climate shocks on banking sector stability by examining the effect of El Niño Southern Oscillation (ENSO) on banking sector distance-to-default. Using dynamic panel data econometric modeling, we investigate the macroeconomic implications of ENSO-induced climate shocks, such as El Niño and La Niña events, on banking sector stability in 51 countries across three regions particularly exposed to the consequences of ENSO oscillations (East Asia and Pacific, Latin America and the Caribbean, and Sub-Saharan Africa) during the period 2000–2020. Our findings show that the adverse effects of these climate shocks on banking sector stability are unevenly distributed among countries, with more pronounced and robust adverse effects of El Niño events in the short-term, particularly in Latin America and the Caribbean and, to a lesser extent, Sub-Saharan Africa. We also document the short-term adverse effects of La Niña events for Latin American and the Caribbean countries. Further estimates suggest that the increase in non-performing loans is a key transmission channel linking El Niño events to banking sector stability. As global warming should intensify the frequency and magnitude of ENSO's cyclical pattern, these findings can help estimate the potential adverse effects of climate change-related natural disasters on banking sector stability and inform future mitigation and adaptation policies
City Makers and the Politics of Urban Diversity Governance. Comparative Approaches from Europe and Asia
No full textInternational audienceThis open access book examines the rising challenges of managing diversity in European and Asian cities. It spotlights the roles of varied city makers - from urban leaders to migrant communities and civil society activists - in negotiating and transforming their city’s diversity governance. The book brings together the contributions of urban studies and migration studies scholars, which offer rich empirical analyses on various European and Asian cities, such as Paris, Singapore, Barcelona, and Guangzhou. Adopting a comparative lens, the book presents a decentered understanding of 'super-diverse' cities, examining shifts in urban policy-making within different geographical contexts, with distinct patterns of migration and diversification. By advancing urban comparison as a research tool, it contributes to the contemporary discussions on the local turn of migration and diversity policies
ForestScan: a unique multiscale dataset of tropical forest structure across 3 continents including terrestrial, UAV and airborne LiDAR and in-situ forest census data
No full textInternational audienceThe ForestScan project was conceived to evaluate new technologies for characterising forest structure and biomass at Forest Biomass Reference Measurement Sites (FBRMS). It is closely aligned with other international initiatives, particularly the Committee on Earth Observation Satellites (CEOS) Working Group on Calibration & Validation (WGCV) AGB cal/val protocols, and is part of GEO-TREES, an international consortium dedicated to establishing a global network of Forest Biomass Reference Measurement Sites (FBRMS) to support EO and encourage investment in relevant field-based observations and science. ForestScan is the first demonstration of what can be achieved more broadly under GEO-TREES, which would significantly expand and enhance the use of EO-derived AGB estimates.We present data from the ForestScan project, a unique multiscale dataset of tropical forest 3D structural measurements, including terrestrial LiDAR scanning (TLS), unmanned aerial vehicle LiDAR scanning (UAV-LS), airborne LiDAR scanning (ALS), and in-situ tree census and ancillary data. These data are critical for the calibration and validation of earth observation (EO) estimates of forest biomass, as well as providing broader insights into tropical forest structure. Data are presented for three FBRMS: FBRMS-01: Paracou, French Guiana; FBRMS-02: Lopé, Gabon; and FBRMS-03: Kabili-Sepilok, Malaysia. Field data for each site include new 3D LiDAR measurements combined with plot tree census and ancillary data, at a multi-hectare scale. Not all data types were collected at all sites, reflecting the practical challenges of field data collection. We also provide detailed data collection protocols and recommendations for TLS, UAV-LS, and plot census measurements for each site, along with requirements for ancillary data to enable integration with ALS data (where possible) and upscaling to EO estimates. We outline the requirements and challenges for field data collection for each data type and discuss the practical considerations for establishing new FBRMS or upgrading existing sites to FBRMS standard, including insights into the associated costs and benefits.</p
Improving electrochemical aptasensor sensitivity for Bacillus cereus spore detection in food safety applications
No full textInternational audienceRapid detection of Bacillus cereus spores is essential for preventing food contamination and spoilage. Many existing methods detect B. cereus vegetative cells rather than spores and cannot be applied directly to foods. Here, we present a combination of aptamers targeting different moieties on the surface of B. cereus spores with rapid electrochemical detection. When DNA aptamers, previously selected for B. cereus spores, were immobilized on screen-printed gold electrodes, they exhibited higher binding capacity than individual aptamers, suggesting a synergistic effect. Additionally, the mixture of rhodamine-labelled aptamers enabled spatial fluorescent visualization of the B. cereus endospore structure, confirming the increased binding efficiency. The electrochemical aptasensor based on three aptamers exhibited a wide dynamic range (102–107 CFU/mL) and low limit of detection (∼1 CFU/mL) using just 15 μL of sample. Validation in spiked salad, using direct spore sensing in rinse water and comparison with the culturing method, confirmed its sensitivity and specificity. These combined aptamer approaches, achieving rapid (15 min) and single-step detection may also be suitable for detecting other foodborne pathogens
Monitoring tropical forests with light drones: ensuring spatial and temporal consistency in stereophotogrammetric products
No full textInternational audienceThis study benefited from an "Investissement d'Avenir" grant managed by the Agence Nationale de la Recherche (CEBA, ref. ANR-10-LABX-25-01), via project PHENOBS. We also acknowledge the support of the UE Biodiversa+ BiodivMon program (Project Coforfunc). We are thankful to Ilona Clocher, Jean-Louis Smock, Jean-Yves Goret, Florian Jeanne and Julien Engel for their help with drone data acquisition and/or processing. Access to the Paracou site and infrastructure (https://paracou.cirad.fr) was granted by CIRAD/Ecofog, and we thank Géraldine Derroire and all Phenobs project participants. We are grateful to Raphaël Pélissier for helping in the initial shaping of the Phenobs project and for his continued support
Integrating problem structuring methods with formal design theory: collective water management policy design in Tunisia
No full textInternational audienceGroundwater management, especially in Mediterranean regions such as Tunisia, is challenging due to diverse stakeholder interests and the arid climate, which makes the sustainability of water resources extremely difficult. This paper proposes an innovative approach to the design of decision and policy alternatives by combining Problem Structuring Methods (PSMs) and the participatory tool based on the Concept-Knowledge (C-K) theory, named Policy-Knowledge, Concepts, Proposals (P-KCP). In a multi-methodological perspective, using Cognitive Maps and Value Trees in combination with P-KCP, the study aims to innovatively generate alternatives to address the sustainability issue of the case study, namely collective groundwater management. The paper provides a practical and adaptable guide to fostering innovation for policy design and generation of alternatives. By bridging decision theory and design theory, the study addresses the methodological gap in alternatives generation and highlights the role of C-K theory for supporting innovative design processes. Integrating PSMs and C-K theory, the multi-methodology advocates participatory approaches to address complex sustainability challenges, provides an adaptable, replicable tool, and encourages the creation of unconventional solutions. Ultimately, this paper offers new collective practices for groundwater management, expanding the set of alternatives through the integration of PSMs and C-K theory and reflecting on the applied multi-methodology
Spillover from flower plantings benefits apple pollination on a small scale
No full textInternational audienceAnimal-mediated pollination is critical to support crop yields but is threatened by the decline of pollinator populations. The establishment of flower plantings in agricultural landscapes is a conservation strategy that aims to provide diverse floral resources for pollinators. Despite several studies on the effect of flower plantings on pollination, their effects remain unclear. In particular, the influence of the distance has been studied through theoretical approaches but field studies are scarce. We conducted field experiments over two years, 2023 and 2024, in the Provence-Alpes-Côte d'Azur region of France, to investigate how co-flowering plantings affect insect flower visitation and crop pollination in apple orchards. We found that the abundance of apple flower visitors, especially wild bees, decreased with the distance from flower plantings, thus suggesting a spillover of flower visitors from flower plantings into adjacent apple trees. Interestingly, we found a non-linear effect of the distance from flower planting on the initial fruit set, which suggests that flower plantings can improve apple pollination at close distances from the plantings (about 33 m). No effect of the distance from flower plantings was observed on the diversity of flower visitors, final apple fruit set or fruit quality. Overall, our results suggest that flower plantings are a promising strategy to support pollinators. Furthermore, as they can increase pollinator abundance in the adjacent apple flowers, flower plantings have the potential to enhance pollination and yield of the adjacent crops. Given the short distance of the observed facilitation effect, we recommend that flower plantings should be spread across farmland in order to promote crop pollination at farm level