With the efflorescence of palaeoscientific approaches to the past, historians have been confronted with a wealth of new evidence on both human and natural phenomena, from human disease and migration to landscape change and climate. These new data require a rewriting of our narratives of the past, questioning what constitutes an authoritative historical source and who is entitled to recount history to contemporary societies. Humanities-based historical inquiry must embrace this new evidence, but to do so historians need to engage with it critically, just as they do with textual and material sources. This article highlights the most vital methodological issues, ranging from the spatiotemporal scales and heterogeneity of the new evidence to the new roles attributed to quantitative methods and the place of scientific data in narrative construction. It considers areas of study where the palaeosciences have “intruded” into fields and subjects previously reserved for historians, especially socioeconomic, climate, and environmental history. The authors argue that active engagement with new approaches is urgently needed if historians want to contribute to our evolving understanding of the challenges of the Anthropocene.

Avec l’efflorescence des approches paléoscientifiques du passé, les historiens ont été confrontés à une multitude de nouveaux indices sur des phénomènes tant humains que naturels, des maladies aux migrations en passant par les transformations du paysage et le climat. Ces données inédites exigent une réécriture des récits portant sur les périodes lointaines, remettant en cause à la fois les fondements de l’autorité des sources historiques traditionnelles et la légitimité des personnes habilitées à narrer le passé aux sociétés contemporaines. Les travaux d’histoire appuyés sur les sciences humaines doivent embrasser ces nouveaux types d’indices ; cependant, pour y parvenir, il est nécessaire pour les chercheurs de s’engager dans cette voie de manière critique, comme ils le font pour les sources textuelles et matérielles. Cet article souhaite mettre en lumière les questions méthodologiques les plus essentielles, qui vont des échelles spatio-temporelles et de l’hétérogénéité des nouvelles preuves au rôle à attribuer aux méthodes quantitatives et à la place des données scientifiques dans la construction narrative. Il examine les domaines d’étude où les paléosciences se sont « immiscées » dans des champs et des sujets auparavant réservés aux historiens, notamment l’histoire socio-économique, climatique et environnementale. Les auteurs soutiennent qu’il est urgent pour ces spécialistes d’explorer activement ces pistes novatrices, s’ils entendent contribuer à l’évolution de notre compréhension des défis de l’Anthropocène.

Gas injection into a liquid cross-flow is examined for the case where the gas is injected beneath a horizontal flat surface. For moderate Froude numbers, the gas pocket that is formed will rise toward the flow boundary under the action of buoyancy, a condition that is conducive to the formation of gas layers for friction-drag reduction on the surface. At the location of gas injection, a plume whose geometry is related to the mass and momentum flux of the injected gas and liquid cross-flow is formed, and the influence of buoyancy is minimal. However, as the gas pocket convects downstream, buoyancy brings the gas back upward to the flow boundary, and leads to the bifurcation of the pocket into two distinct branches, forming a stable ‘V’-shape. Under some conditions, the flow between the two gas branches is almost entirely liquid, while for others there exists a bubbly flow or a continuous sheet of gas between the branches. The sweep angle and cross-sectional geometry of the gas branches are related to free-stream speed and boundary-layer thickness of the liquid cross-flow, the mass-injection rate of the gas, the diameter of the injection orifice and the gas outlet mean velocity and gas–jet angle. Data for a range of experimental conditions are used to scale the flow and results are compared to numerical computations of the flow, and these data are used to illustrate the underlying flow processes responsible leading to the formation the stable and straight gas branches. A simple model based on the balance of forces around a stable gas branch is presented and used to scale the observed data, and we use the results of this analysis and the computations to discuss how the process of gas injection may interact with the formation of the stable gas pockets farther downstream.

Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene–nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient–genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.