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Processes that create centralities and hierarchies in human geography
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Comprehensive Lipid Profiling of Grape Musts: Impact of Static Settling
No full textInternational audienceLipids are crucial in alcoholic fermentation, influencing yeast metabolism by providing nutrients and modulating membrane composition [1]. They also serve as precursors to aromatic compounds shaping wine sensory profiles [2]. While sterols and unsaturated fatty acids have been extensively studied, the overall lipid composition in grape musts remains poorly understood. Many lipid families, including phospholipids, sphingolipids, and glycolipids, have been largely overlooked. This study aims to provide a comprehensive lipid profile by identifying as many species as possible, beyond the commonly studied sterols and fatty acids.Clarification, a widespread winemaking process, significantly reduces lipid availability, potentially leading to slow or stuck fermentations and undesirable aromas [4-6]. This study examines white grape musts from eight varieties and the impact of static settling on lipid composition. Initially, untargeted LC-MS QToF was used to capture a broad lipid spectrum, guiding targeted quantification methods. Free fatty acids, total fatty acids, and sterols were quantified via GC-MS, while phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, steryl esters, glycerolipids, and ceramides were analyzed by LC-MS.For the first time in grape must analysis, an untargeted LC-MS QToF approach enabled the detection of 562 lipid compounds, 112 of which were confirmed as sphingolipids, fatty acids, phospholipids, glycerolipids, and sterols. Some lipid subclasses, such as (lyso)phosphatidylethanolamines, (lyso)phosphatidylinositols, and steryl esters, had never been reported in grape musts. Targeted quantification by GC-MS and LC-MS identified 375 lipids across nine subclasses, with 297 displaying significant differences (ANOVA α=0.05). Clarification significantly affected lipid concentrations, impacting 73% of detected species (Kruskal-Wallis α=0.05), particularly sterols, fatty acids, and phospholipids—key molecules for yeast metabolism.These findings underscore the importance of studying the full complexity of lipid composition in grape musts and suggest that revising clarification practices could help preserve essential lipids, thereby improving fermentation efficiency and wine quality. Overall, this study provides new insights into the lipid composition of grape musts and the nutritional challenges yeast may face during fermentation
Exploring the paleoclimatic potential of a 1000-year tree-ring chronology from archaeological and living oaks from central France
No full textInternational audienceTree rings are valuable archives for reconstructing natural climate variability with high temporal resolution over the last millennium, providing critical context for current global warming and enhancing our understanding of anthropogenic and natural climate forcings. However, global climate reconstructions rely on regional studies that are unevenly distributed across space and time. In Europe, tree-ring widths have been widely used to reconstruct temperature and precipitation, yet millennial-scale climate reconstructions are lacking in France, particularly for central France and, more broadly, lowland regions. New data from this region would enhance our understanding of hydroclimatic variability and its drivers in western Europe while also improving the accuracy of climate reconstructions for both European and Northern Hemisphere. We examined the feasibility of constructing a millennial chronology using archaeological material and living trees from central France, collected and dated over the last few decades by numerous French dendrochronologists. The initial dataset consisted of 5,745 archaeological wood samples and 129 living oaks, spanning 45-48.5°N and -2-5.5°E, and covering from 696 to 2023 CE. From this dataset, we produced several reconstructions using various series selection criteria, detrending methods, and calibration and verification methods across different time periods. These reconstructions were then compared, and the decision-making process was evaluated. The reconstructions’s skills, consistent with results obtained in previous studies, along with the agreement between our reconstruction and published European climate reconstructions and paleo-reanalyses, highlight the potential of this French new dataset for reconstructing May-July hydroclimatic variability over the last millennium in this region of Europe
The Asselian palynoflora from the Autunian series (Muse oil-shale beds, Autun Basin, France): new insights on early Permian equatorial palaeoflora and palaeoenvironments
No full textInternational audienceThe Muse oil-shale beds (Muse OSB) of the Permian Muse Formation in the Autun Basin (France) have received attention for their exceptionally well-preserved flora and fauna throughout many decades. Recent CA-ID-TIMS U/Pb radiometric datings place the Muse section in the lower Asselian (∼298.6 Ma), leading to a re-examination of the palynoflora using an alternative palynological method. Twelve productive samples provide a detailed taxonomic and quantitative evaluation of the palynoflora. The new data revealed now two distinct palynological assemblages, Muse-A in the lower part and Muse-B in the middle-upper part of the Muse section, assigned to a peat swamp forest environment dominated by cordaitalean conifers, alongside medullosalean cycads and callistophytalean seed ferns, with an undergrowth of lycophytes and ferns. Additionally, a forest dominated by walchian conifers (Voltziales) would be present but more distant from the lake. Vegetation dynamics between these associations are generally stable, except for an increase in Cordaitales at the expense of Voltziales. This variation, observed throughout the Autun Basin, seems to be affected by seasonal climate-driven changes. The co-occurrence in both assemblages of Permian xerophytic element
"Nocturne berlinois : la périphérie comme Abweichbild dans Wach d’Albrecht Selge"
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Les mots du chantier. L’usage du vocabulaire technique dans les duché et comté de Bourgogne aux XIVe et XVe siècle
No full textInternational audienceThe researcher working on the accounts of medieval construction sites immediately faces a problem understanding the technical vocabulary, which is often rather inconsistent and exhibits significant topographical and chronological variability. This is the experience of the authors: H. Mouillebouche, who studies the construction accounts of ducal castles in the Duchy of Burgundy, notably the ducal palace in Dijon, and A. Giordano, who is writing a dissertation under the supervision of the former on the management of construction and maintenance of castles in the County of Burgundy. The duchy and the county, united under the same princes from 1360 to 1470, experienced some administrative standardization, with accounts formatted according to the norms imposed by the Chambre des Comptes of Dijon. These accounts are systematically written in French, following standardized headings and providing more or less synthetic analyses of locally written receipts, some of which have been preserved. However, the duchy and county belong to two quite different cultural areas: one within the kingdom, the other within the empire, with linguistic but also technical and construction-specific particularities. From a practical perspective, we overcame the vocabulary variability by compiling a collaborative lexicon, an indispensable tool for understanding construction archives. Yet, we wish to take advantage of this conference theme to reflect on the meaning of this vocabulary variability from social, technical, and philological perspectives. First, it is necessary to consider the words used by the craftsman, by the notary drafting the receipt, and then by the receiver recording the accounts—following, correcting, or awkwardly copying the receipt. The transition from oral to written language inevitably involves interpretation, often experienced as correction. But when the historian, having applied all their expertise, does not understand the text they are reading, they may legitimately wonder whether the clerk who wrote it understood what they were copying. The standardization of account hearings does not prevent the use of regional vocabulary, which can be easily mapped (“fenestres flamanches” in the duchy, “fenestres françoises” in the county...). One must also question whether local words correspond to linguistic particularities or to local construction techniques (“loiches” from the Saône plain, “poix” from the Jura forests...). It is also possible to investigate whether there is a correlation between the richness and precision of technical vocabulary and the social or technical level of the craftsman or clerk: do the master masons of the duchy, or even those of the king when serving the duke, possess a more precise vocabulary than local artisans? Some particularly obscure receipts seem to originate from especially skilled craftsmen. However, one must distinguish between the use of mastered standardized vocabulary and the use of an obscure professional jargon, which does not always indicate a high level of technical expertise (yesterday as today...). Finally, the regionalization or standardization of vocabulary could be the result of vernacular construction methods or, conversely, of exchanges between construction sites and regions. Words travel with people. And if one can recognize, in stone remains, the influence of the presence of a master builder, perhaps one could also find, in the account books, traces of the words they taught. It will also be necessary to go beyond the study’s framework to measure the influence of the language and words from the Empire, Île-de-France, or the Burgundian Netherlands.Le chercheur qui travaille sur les comptes de chantiers médiévaux se trouve immédiatement confronté à un problème de compréhension du vocabulaire technique, qui est souvent assez peu uniformisé, et connaît une grande variabilité topographique et chronologique. C’est l’expérience qu’ont faite les auteurs, H. Mouillebouche, qui travaille sur les comptes de construction des châteaux ducaux du duché de Bourgogne et notamment de l’hôtel ducal de Dijon, et A. Giordano, qui rédige une thèse sous la direction du premier sur la gestion de la construction et de l’entretien des châteaux du comté de Bourgogne. Le duché et le comté, réunis de 1360 à 1470 dans les mains des mêmes princes, connaissent une certaine uniformisation administrative, avec des comptes mis en forme selon les normes imposées par la chambre des Comptes de Dijon. Ils sont systématiquement rédigés en français, selon des rubriques homogénéisées, et en donnant l’analyse plus ou moins synthétique de quittances rédigées localement, et qui sont parfois conservées. Mais le duché et le comté appartiennent à deux aires culturelles assez différentes, l’un au royaume, l’autre en empire, avec des spécificités linguistiques mais aussi techniques et constructives. D’un point de vue pratique, nous avons surmonté la variabilité du vocabulaire par la rédaction d’un lexique collaboratif, outil indispensable pour comprendre les archives de construction. Mais nous voudrions profiter du thème de ce colloque pour nous interroger sur le sens à donner à cette variabilité du vocabulaire, dans une approche sociale, technique et philologique. Il faut tout d’abord s’interroger sur les mots employés par l’artisan, par le notaire qui rédige la quittance, puis par le receveur qui enregistre les comptes, en suivant, en corrigeant, ou en recopiant maladroitement la quittance. Le passage de la langue orale à la langue écrite induit forcément une interprétation, vécue comme une correction. Mais quand l’historien, ayant déployé toute sa science, ne comprend pas le texte qu’il lit, il peut légitimement se demander si le clerc qui l’a écrit comprenait ce qu’il recopiait. L’uniformisation de l’audition des comptes n’empêche pas l’usage d’un vocabulaire régional, qu’on peut aisément cartographier (« fenestres flamanches » en duché, « fenestres françoises » en comté…) Encore faut-il se demander si les mots locaux correspondent à des particularismes linguistiques, ou a des techniques de constructions locales (« loiches » de la plaine de la Saône, « poix » des forêts du Jura…) On peut également essayer de voir s’il existe une corrélation entre la richesse et la précision du vocabulaire technique, et le niveau social ou technique de l’artisan ou du clerc : les maîtres des œuvres de maçonnerie du duché, voire ceux du roi quand ils sont au service du duc, ont-ils un vocabulaire plus précis que les artisans locaux ? Quelques quittances particulièrement hermétiques semblent émaner d’artisans particulièrement compétents. Mais il faudra pouvoir distinguer l’usage d’un vocabulaire normalisé maîtrisé et celui d’un jargon professionnel abscons, qui n’est pas toujours preuve d’une grande maîtrise technique (hier comme aujourd’hui…) Enfin, la régionalisation ou l’uniformisation du vocabulaire pourraient être les conséquences de méthodes constructives vernaculaires ou au contraire d’échanges entre chantiers, entre régions. Les mots voyagent avec les hommes. Et si l’on est capable de reconnaître, dans les vestiges de pierre, l’influence du passage d’un maître bâtisseur, peut-être pourrait-on aussi retrouver, dans les livres de comptes, la trace des mots qu’il a enseigné. Il faudra également sortir du cadre de l’étude pour mesurer l’influence de la langue et des mots de l’Empire, d’Île- de-France ou des Pays-Bas bourguignons
Impact de la régulation naturelle sur la flore adventice et le rendement. Une étude menée en région Bourgogne-Franche-Comté a quantifié les services de régulation naturelle fournis par les invertébrés et vertébrés granivores
No full textNational audienceCONTEXTE La présence de plantes adventices dans une culture est généralement associée à une perte de rendement. Or, dans un contexte d’interdiction de nombreuses substances herbicides, l’effet d’une régulation naturelle par les organismes consommateurs de graines (granivores) sur la dynamique des adventices et le rendement de la culture reste peu quantifié. ÉTUDE Une équipe de l’UMr agroécologie (Inrae et Institut agro) a mené une étude sur 28 parcelles de blé en région Bourgogne-Franche-Comté en 2021 et 2022, comparant des systèmes en agriculture de conservation des sols et en agriculture conventionnelle. Différentes cages expérimentales incluant ou excluant les granivores vertébrés et invertébrés (principalement carabes et petits mammifères) ont été installées pour quantifier leur impact sur le développement des adventices et donc indirectement sur le rendement de la culture. RÉSULTATS La cage « Contrôle » (sans granivores ni ajout de graines adventices) a permis d’évaluer le rendement maximal de blé en l’absence de compétition avec les adventices, tandis que la cage « sans prédation » de graines adventices (sans granivores et avec ajout de graines adventices) révèle que la compétition adventice/culture cause une réduction moyenne de 80% du rendement de blé. La cage « Prédation partielle » (permettant l’accès des invertébrés granivores uniquement) et la cage « Prédation totale » (permettant l’accès des invertébrés et des vertébrés granivores) ont permis de limiter cette perte à respectivement 45% et 60%. Dans les parcelles en agriculture de conservation des sols, la biomasse adventice est plus faible qu’en agriculture conventionnelle mais le rendement du blé n’est pas significativement plus élevé
