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A Discussion About Violin Reduction: Geometric Analysis of Contour Lines and Channel of Minima
No full textSome early violins have been reduced during their history to fit imposed morphological standards, while more recent ones have been built directly to these standards. Geometric differences exist between reduced and unreduced instruments, particularly in their contour lines and channel of minima. In a recent preliminary work, we computed and highlighted those two features for two instruments using triangular 3D meshes acquired by photogrammetry, whose fidelity has been assessed and validated with sub-millimetre accuracy. We propose here an extension to a corpus of 38 violins, violas and cellos, and introduce improved procedures, leading to a stronger discussion of the geometric analysis. We first recall the material we are working with. We then discuss how to derive the best reference plane for the violin alignment, which is crucial for the computation of contour lines and channel of minima. Finally, we show how to compute efficiently both characteristics and we illustrate our results with a few examples
The Missing Ecology in Affordance Management
No full textKo and Neuberg’s framework links life-history priorities to ecological affordances but foregrounds conditions of relative stability, thereby underrepresenting volatility. Volatility is a constitutive ecological parameter, altering affordance availability and reliability. Incorporating anticipated affordances, stratified resilience, and volatility as a higher-order constraint sharpens the model’s theoretical scope and ecological validity under conditions of systemic crisis
Un poquito más nos ha unido el Covid’. Dinamiche di autogestione durante la pandemia in una comunità indigena dell'Amazzonia peruviana
No full textQuesto articolo esplora le trasformazioni sociali e politiche avvenute durante il periodo pandemico all’interno di una comunità indigena dell'Amazzonia peruviana, situata nel cuore della regione Madre de Dios. Questo studio etnografico permetterà di riflettere sulle capacità di coordinazione e di auto-governo messe in atto per rispondere ad una crisi sanitaria e sociale da una collettività usualmente frammentata e conflittiva. Situata nel cuore sia di un punto nevralgico del commercio internazionale del legname, che nella spina dorsale del sistema di viabilità della regione, la comunità di Shintuya, di etnia prevalentemente arakmbut, si presenta come una realtà socio-culturale estremamente complessa, dominata da uno spirito di individualismo, privatizzazione e accumulo di capitale economico. In quanto testimonianza emblematica dei principali fenomeni di trasformazione sociali ed economici presenti negli ultimi cinquant'anni nelle società indigene delle frontiere estrattive, Shintuya diventa nel 2020 un osservatorio eccezionale sulle capacità collettive di risposta alla crisi a partire da un ripensamento sui concetti di modernità, benessere economico e “buen vivir”
On the use of industrial steel mill scale as a high-density energy carrier: Part II. Microstructural and chemical evolution over cycling
No full textRecently, iron powder has been considered as a high-density energy carrier, or sustainable metal fuel. The potential of low-cost steel processing by-product, mill scale powder, was investigated in the first part of this study through two cycles of hydrogen-based direct reduction and combustion in a metal cyclonic burner. This second part focuses on the microstructural and chemical evolution of the powder over its cycling, using a combination of state-of-the-art microscopy (scanning electron microscopy and scanning transmission electron microscopy, coupled with energy-dispersive x-ray spectroscopy), surface area BET measurements, x-ray diffraction and thermodynamic simulations. The distribution of the chemical elements is initially highly inhomogeneous and concentrated on the powder surface, but gets homogenised by the combustion process. New Ca and Si-rich oxide phase(s) form during the solidification of the combusted powders, while the remaining chemical elements (Mn, Cu, Ni, Ti, Al, Cr, Mg) remain in solid solution in the iron oxide phases. Enriched zones of Cu and Ni are observed in the Fe oxide nanoparticles, corresponding to their favoured evaporation, while Mn is homogeneously distributed in the Fe oxide nanoparticles. Si and Cr oxide nanoparticles are also detected, while Al hardly evaporates. A satisfactory heat release efficiency of 0.84–0.9 is measured for the reduced mill scale, even if slightly lower than pure Fe (0.88–0.91), confirming its potential for use as metal fuel
Scientific Methodology in Nineteenth Century Britain: Volume IV, Forces, Fields, and Energy: Physical Sciences
No full textThis collection of primary sources examines scientific methodology in Britain during the long nineteenth century. The nineteenth century begins with what was still a largely Newtonian perspective on the nature of matter and the physical world – Newtonian bodies moving through space, guided by a collection of forces, with gravity foremost among them. By the end of the century, physical science had refocused itself around the concept of energy, the first moves toward the understanding of atomic structure had been undertaken, and electricity and magnetism were understood in terms of fields of force. This volume examines primary sources related to the philosophy of the physical sciences, and will be of great interest to students of the history of philosophy and the history of science
Scientific Methodology in Nineteenth Century Britain: Volume II, Deep Time: Geology and Evolution
No full textThis collection of primary sources examines scientific methodology in Britain during the long nineteenth century. Over the course of the nineteenth century, emblematically but not exclusively represented by the work of Charles Darwin, natural science reconfigured the ways in which practitioners would treat the sciences of "deep time" – especially geology and the new theory of natural selection. This volume uses primary sources and editorial commentary to examine the topics of geology and evolution in this period. This title will be of great interest to students of the history of philosophy and the history of science
The Cultural History of Solitude in Antiquity: An Introduction
No full textThis article presents a novel approach to the study of the cultural history of solitude in antiquity. It presents solitude in comparative perspective, notably in conversation with anthropology, paleolithic studies, zoology, as well as with a broad range of ancient philological sources that range from ancient Egypt to to India to classical Greece and Rome down to Jewish Alexandria and late-antique Christianity. As it shows, the history of solitude is not a simple fall from communitarian grace to individual alienation, nor is it a simple rise from a conformist mass to triumphant autonomy: neither lapsarian nor whiggish teleology, or vision’s of history’s necessary arc, are adequate to the complex role that the uses, the cultivation, the culture of solitude has played throughout human history. And I say ‘throughout’, for, far from being the invention of Augustine’s meditations on original sin, or the medieval confessional, or Montaigne’s tower, or the mass-print paperback, or British romanticism, or the French revolution or bourgeois counter-revolution, or neo-liberal late-stage capitalist alienation, solitude is as old as hominids, and perhaps as old as our primate ancestors: a recent ethological study suggested that a certain eye-covering gesture by captive Colchester mandrillsin—usually highly sociable monkeys that live in troops—signaled a desire to be left alone. Sad solitude, bad solitude, useful solitude; loneliness on a desert island, loneliness in a crowd, or a moment to one’s own in deep forest or a room or a city or a tomb: all of these are as old as culture, from Latin cultura, meaning a way of living, dwelling, adorning, growing, caring for others (plants, animals, gods) and taking ‘care of the self’. To study the cultural history of solitude is to study practices but also ways of speaking and thinking, ways of approaching what it means, in the words of the American poet Wallace Stevens, to ‘live in a place / that is not our own and, much more, not ourselves’. He adds: ‘And hard it is in spite of blazoned days’
