Fluid chemistry in the Solitaire and Dodo hydrothermal fields of the Central Indian Ridge

Fluid chemistry and microbial community patterns in chimney habitats were investigated in two hydrothermal fields located at the Central Indian Ridge. Endmember hydrothermal fluid of the Solitaire field, located ~3 km away from the spreading center, was characterized by moderately high temperature (307°C), Cl depletion (489 mm ), mildly acidic pH (≥4.40), and low metal concentrations (Fe ≤ 105 μm and Mn = 78 μm ). Chloride depletion indicates that the subseafloor source fluid had undergone phase separation at temperatures higher than ~390°C while the metal depletion was likely attributable to fluid alteration occurring at a venting temperature of around 307°C. These different temperature conditions suggested from fluid chemistry might be associated with an off‐spreading center location of the field that allows subseafloor fluid cooling prior to seafloor discharge. The microbial community in the chimney habitat seemed comparable to previously known patterns in typical basalt‐hosted hydrothermal systems. Endmember hydrothermal fluid of the Dodo field, standing on center of the spreading axis, was characterized by high H₂ concentration of 2.7 mm . The H₂ enrichment was likely attributable to fresh basalt–fluid interaction, as suggested by the nondeformed sheet lava flow expansion around the vents. Thermodynamic calculation of the reducing pyrite–pyrrhotite–magnetite (PPM) redox buffer indeed reproduced the H₂ enrichment. The quantitative cultivation test revealed that the microbial community associated with the hydrothermal fluid hosted abundant populations of (hyper)thermophilic hydrogenotrophic chemolithoautotrophs such as methanogens. The function of subseafloor hydrogenotrophic methanogenic populations dwelling around the H₂‐enriched hydrothermal fluid flows was also inferred from the ¹³C‐ and D‐depleted signature of CH₄ in the collected fluids. It was observed that the hydrothermal activity of the Dodo field had ceased until 2013.     

Holocene land-use evolution and associated soil erosion in the French Prealps inferred from Lake Paladru sediments and archaeological evidences

A source-to-sink multi-proxy approach has been performed within Lake Paladru (492 m a.s.l., French Prealps) catchment and a 6-m long sediment sequence retrieved from the central lacustrine basin. The combination of minerogenic signal, specific organic markers of autochthonous and allochthonous supply and archaeological data allows the reconstruction of a continuous record of past human disturbances. Over the last 10,000 years, the lacustrine sedimentation was dominated by autochthonous carbonates and the watershed was mostly forest-covered. However, seven phases of higher accumulation rate, soil erosion, algal productivity and landscape disturbances have been identified and dated from 8400 to 7900, 6000 to 4800, 4500 to 3200, 2700 to 2050 cal BP as well as AD 350–850, AD 1250–1850 and after AD 1970. Before 5200 cal BP, soil erosion is interpreted as resulting from climatic deterioration phases towards cooler and wetter conditions. During the Mid-Late Holocene period, erosion fluxes and landscape disturbances are always associated with prehistorical and historical human activities and amplified by climatic oscillations. Such changes in human land-used led to increasing minerogenic supply and nutrients loading that affected lacustrine trophic levels, especially during the last 1600 years. In addition, organic and molecular markers document previously unknown human settlements around Lake Paladru during the Bronze and the Iron Ages.     

The Henequen Ports of Yucatan’s Gilded Age

Over the last two centuries, the coast has played a major role in the economy of Yucatán, and has served as a key venue in its growing engagement in the global economy. A prominent chapter in this history took place during the Gilded Age (1860–1915), which saw the emergence of a powerful plantation class whose wealth was based on meeting international demand for the fiber of the agave, or henequen plant, which was used to manufacture rope, cordage, and twine. The cultivation of this plant gave rise to hundreds of plantations, and an accompanying infrastructure of haciendas, fiber processing plants, and an extensive regional network of railways for transporting henequen to the port of Progreso, from whence it was exported to North America and Europe. As part of this infrastructure, several plantation owners laid rail lines from their haciendas to the coast and built small ports for shipping their henequen to Progreso. These ports, which are documented in these pages, represented a substantial capital outlay, and were built under the shadow of the gathering clouds of the Mexican Revolution. Viewed in retrospect, they offer an insightful perspective on the economic outlook of the Yucatecan elites in the dawn of the modern age.     

CONSUMER PERCEPTIONS OF SPONSORSHIP IN THE ARTS

This article investigates consumers’ perceptions of three types of sponsors that play a role in backing financially Canadian artistic and cultural organisations: government ministries (or departments), Crown corporations and private companies. In addition to the type of sponsor and the nature of the sponsorship (philanthropic or commercial), the perceived congruence between the sponsor and the sponsored event (strong as opposed to weak), and the form of arts and cultural events (high art versus popular art and performing arts versus heritage arts) are explored in an experimental setting combining within‐subjects and between‐subjects factors. The main hypothesis of this research was that consumers’ perceptions are not the same when it comes to the different kinds of sponsors that evolve in the cultural and art fields. As the researchers explored this issue, they observed that significant differences do exist. It is believed that the rich findings of this study will be useful to civil servants.     

Pleasure: ‘The Choice of Hercules’

In this article I contend that John Stuart Mill’s Utilitarianism has been widely misunderstood, and hence the importance of his philosophical project has been diminished. This misunderstanding arises primarily from misconceptions regarding Mill’s definition of pleasure. However, these misconceptions may be successfully resolved by reflecting on Mill’s educational roots and his commitment to Greco-Roman philosophy. In particular, I hold that a deeper understanding of Mill’s philosophical progenitors (i.e., Aristotle and Epicurus) would lead us to conclude that for Mill the “pleasures” of the Utilitarian project are in the final analysis nothing other than the “pleasures” of the mind and conscience. Thus, by following Mill’s line of reasoning and adhering to some of the salient points of his work, specifically in Chapter 2 of Utilitarianism, we may reach a richer and more nuanced understanding of his impressive philosophical project.