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Fragments de ‘rondels’ aux armes de Charles Quint
No full textA propos de fragments de médaillons aux armes de Charles Quint retrouvés sur le site du Coudenberg à Bruxelle
Rapport technique d'expertise réf. exp-147 du 12/01/2016 - Demandeur: Mr. Armand Stockmans, SOMEX S.A., Malachietstraat 2 - 2030 Antwerpen, 09/12/2015
No full textHet reliekschrijn van Sint-Odilia (1292) onder de loep : een nieuwe bijdrage aan de studie van het oudst gedateerde kunstwerk op hout van de Lage Landen
No full textBrittle faulting and tectonic stress history on the western margin of the Congo Basin between Kinshasa and Brazzaville: implications for the evolution of the Malebo Pool and the Congo River.
No full textThe history of brittle faulting and associated paleostress states has been investigated in the rapids of the Congo River at the outlet of the Malebo Pool between Kinshasa (Democratic Republic of the Congo) and Brazzaville (Republic of the Congo). The aim of this study was to unravel the Meso-Cenozoic tectonic evolution of the western margin of Central Africa, as well as to investigate the dynamic evolution of the Pool and the capture of the Congo Basin drainage system by the Lower Congo River through the Central African Atlantic swell that formed between the Congo Basin and the Atlantic Ocean. We reviewed the geological evolution of the Pool area using recent data and new field observations to develop a consistent stratigraphic model for both sides of the Congo River. We collected a significant amount of data faults and fractures in the early Paleozoic Inkisi arkosic sandstones, identified four successive data subsets and determined their related paleostress tensors trough an iterative process utilizing relative chronological indications. All paleostress states exhibit a a strike-slip faulting regime, with varying orientation of horizontal principal compression. The timing of faulting was constrained by indirect observations based on the updated understanding of the Pool s evolution. The geodynamic interpretation of the brittle stages considered potential sources of compressional stress arising from plate boundaries and from the oceanic ridge push. A polyphase brittle tectonic history was identified, characterized by the gradual appearance of newly formed faults and reactivation of the existing ones, leading to the gradual saturation of the host rock with fractures. The most recent event let to a significant imprint on the current landscape and is believed to have facilitated the connection of the drainage system of the Congo Basin to the Atlantic coast in the Oligocene period. The current stress state, determined from earthquake focal mechanisms, aligns with the most recent paleostress state identified determined from fault-slip data, displaying similar stress axis orientations but with consistent with a transpressional stress regime instead of a strike-slip one
Evaluating present-day and future impacts of agricultural ammonia emissions on atmospheric chemistry and climate
No full textAgricultural practices are a major source of ammonia (NH3) in the atmosphere, which has implications for air quality, climate, and ecosystems. Due to the rising demand for food and feed production, ammonia emissions are expected to increase significantly by 2100 and would therefore impact atmospheric composition such as nitrate (NO3-) or sulfate (SO2-4) particles and affect biodiversity from enhanced deposition. Chemistry–climate models which integrate the key atmospheric physicochemical processes with the ammonia cycle represent a useful tool to investigate present-day and also future reduced nitrogen pathways and their impact on the global scale. Ammonia sources are, however, challenging to quantify because of their dependencies on environmental variables and agricultural practices and represent a crucial input for chemistry–climate models. In this study, we use the chemistry–climate model LMDZ–INCA (Laboratoire de Météorologie Dynamique–INteraction with Chemistry and Aerosols) with agricultural and natural soil ammonia emissions from a global land surface model ORCHIDEE (ORganising Carbon and Hydrology In Dynamic Ecosystems), together with the integrated module CAMEO (Calculation of AMmonia Emissions in ORCHIDEE), for the present-day and 2090–2100 period under two divergent Shared Socioeconomic Pathways (SSP5-8.5 and SSP4-3.4). Future agricultural emissions under the most increased level (SSP4-3.4) have been further exploited to evaluate the impact of enhanced ammonia emissions combined with future contrasting aerosol precursor emissions (SSP1-2.6 – low emissions; SSP3-7.0 – regionally contrasted emissions). We demonstrate that the CAMEO emission set enhances the spatial and temporal variability in the atmospheric ammonia in regions such as Africa, Latin America, and the US in comparison to the static reference inventory (Community Emissions Data System; CEDS) when assessed against satellite and surface network observations. The CAMEO simulation indicates higher ammonia emissions in Africa relative to other studies, which is corroborated by increased current levels of reduced nitrogen deposition (NHx), a finding that aligns with observations in west Africa. Future CAMEO emissions lead to an overall increase in the global NH3 burden ranging from 59 % to 235 %, while the NO3- burden increases by 57 %–114 %, depending on the scenario, even when global NOx emissions decrease. When considering the most divergent scenarios (SSP5-8.5 and SSP4-3.4) for agricultural ammonia emissions, the direct radiative forcing resulting from secondary inorganic aerosol changes ranges from −114 to −160 mW m−2. By combining a high level of NH3 emissions with decreased or contrasted future sulfate and nitrate emissions, the nitrate radiative effect can either overcompensate (net total sulfate and nitrate effect of −200 mW m−2) or be offset by the sulfate effect (net total sulfate and nitrate effect of +180 mWm-2). We also show that future oxidation of NH3 could lead to an increase in N2O atmospheric sources from 0.43 to 2.10 Tg N2O yr−1 compared to the present-day levels, representing 18 % of the future N2O anthropogenic emissions. Our results suggest that accounting for nitrate aerosol precursor emission levels but also for the ammonia oxidation pathway in future studies is particularly important to understand how ammonia will affect climate, air quality, and nitrogen deposition
Compte-rendu de Clélia Lacam, Le Bleu et le Noir; Jeux de pouvoirs dans une mission catholique féminine (Gbaon, 1911-1955)
No full textReport of a scientific work devoted to the history of twho female religious congregations in Gabon, from a perspective at the intersection of gender and religion history, highlighting the dynamics of agency, subalternity and intersectionnality
The genus <i>Amphoterus</i> Bezzi: taxonomic notes on a rare Afrotropical hover fly genus
No full textCatastrophic disruption of asteroid 2023 CX1 and implications for planetary defence
No full textMitigation of the threat from airbursting asteroids requires an understanding of the potential risk they pose for the ground. How asteroids release their kinetic energy in the atmosphere is not well understood due to the rarity of large impacts. Here we present a comprehensive, space-to-laboratory characterization of an impact of an L chondrite, which represents a common type of Earth-impacting asteroid. Small asteroid 2023 CX1 was detected in space and predicted to impact over Normandy, France, on 13 February 2023. Observations from several independent sensors and reduction techniques revealed an unusual but potentially high-risk fragmentation behaviour. The nearly spherical 650 ± 160 kg (72 ± 6 cm diameter) asteroid catastrophically fragmented at a dynamic pressure of 4 MPa around 28 km altitude, releasing 98% of its total energy in a concentrated region of the atmosphere. The resulting shock wave was spherical, not cylindrical, and released more energy closer to the ground. This type of fragmentation increases the risk of substantial damage at ground level. These results warrant consideration for a planetary defence strategy for cases where a >3–4 MPa dynamic pressure is expected, including planning for evacuation of areas beneath anticipated disruption locations
Thesaurus of Early Modern Archival Sources (TEMAS)
No full text(NL) Deze tweetalige databank (NL/FR) reikt definities aan voor circa 450 archivalische documenttypes uit de vroegmoderne periode. Ze is ontwikkeld met het expliciete doel om archiefgebruikers te ondersteunen bij de interpretatie van archivalische beschrijvingen in inventarissen. Gebruikers kunnen de relationele databank of een overzichtelijke PDF downloaden.(FR) Cette base de données bilingue (NL/FR) propose des définitions pour environ 450 types de documents archivistiques de la période moderne. Elle a été développée dans le but explicite de soutenir les utilisateurs d'archives dans l'interprétation des descriptions archivistiques dans les instruments de recherche. Les utilisateurs peuvent télécharger la base de données ou un document PDF dérivé.(ENG) This bilingual dataset (Dutch/French) offers definitions for approximately 450 archival document types from the early modern period. It was developed with the explicit purpose of supporting archive users in the interpretation of archival descriptions in finding aids. Users can download the database or a derived PDF document.This dataset is published and preserved in SODHA - Belgian Data Archive for Social Sciences and Digital Humanities. ORFEO provides a bibliographic reference only; data files are accessible exclusively via the DOI link below
Estimation et modélisation des concentrations de PM2.5 à Kinshasa (2022–2024) à partir des AOD satellitaires MODIS-MAIAC et des paramètres météorologiques
No full textCette étude vise à estimer les concentrations de PM2.5en surface à Kinshasa à partir des données satellitaires d’épaisseur optique des aérosols (AOD), compte tenu de l’absence de réseau de surveillance au sol dans cette ville. Les estimations satellitaires ont été comparées aux rares mesures in situ réalisées entre 2022 et 2024 sur deux sites : l’Ambassade des États-Unis (Site 1) et l’Université de Kinshasa (Site 2). Deux modèles de régression ont été appliqués : une régression linéaire simple (RLS) reliant directement l’AOD aux PM2.5, et une régression multi-linéaire (MLR) intégrant des paramètres météorologiques sélectionnés (température, direction du vent et précipitations). Le modèle MLR améliore les performances par rapport au modèle RLS. Au Site 1, le coefficient de détermination passe de R² = 0,51 à R² = 0,57, et au Site 2 de R² = 0,65 à R² = 0,73, avec une réduction du MAE et du RMSE. L’analyse saisonnière montre de meilleures performances pendant la saison des pluies que pendant la saison sèche. Ces résultats offrent un potentiel important pour renforcer la surveillance de la qualité de l’air et soutenir l’élaboration de politiques environnementales et sanitaires plus efficaces dans les régions où les capacités de mesure au sol demeurent limitées