Lute, Vihuela, and Early Guitar

Producción CientíficaLutes, guitars, and vihuelas were the principal plucked instruments in use in Europe until around 1800. Ancient forms of the lute existed in many parts of the ancient world, from Egypt and Persia through to China. It appears to have become known in Europe, where its earliest associations were with immigrants such as the legendary Persian lutenist Ziryab (b. c. 790–d. 852), who was established in Moorish Spain by 822. The origins of the various flat-backed instruments that eventually became guitars are more difficult to trace. The vihuela is one such instrument that evolved in the mid-15th century and was prolific in Spain and its dominions throughout the 16th century and beyond. Very few plucked instruments, and only a handful of fragmentary musical compositions, survive from before 1500. The absence of artifacts and musical sources prior to 1500 has been a point of demarcation in the study of early plucked instruments, although current research is seeking to explore the continuity of instrumental practice across this somewhat artificial divide. In contrast, perhaps as many as thirty thousand works—perhaps even more—for lute, guitar, and vihuela survive from the period 1500–1800. The music and musical practices associated with them are not well integrated into general histories of music. This is due in part to the use of tablature as the principal notation format until about 1800, and also because writers of general histories of music have for the most part ignored solo instrumental music in their coverage. (For example, the Oxford Anthology of Western Music, Vol. 1 (2018), designed to accompany chapters 1–11 of Richard Taruskin’s Oxford History of Western Music, does not contain a single piece of instrumental music prior to Frescobaldi [1637]). Contrary to this marginalized image, lutes, vihuelas, and guitars were a revered part of courtly musical culture until well into the 18th century, and constantly present in urban contexts. After the development of basso continuo practice after 1600, plucked instruments also became frequent in Christian church music, although the lute was widely played by clerics of all levels, particularly during the Renaissance. It was also one of the principal tools used by composers of liturgical polyphony, in part because tablature was the most common way of writing music in score. From the beginning of music printing, printed tablatures played a fundamental role in the urban dissemination of music originally for church and court, and plucked instruments were used widely by all levels of society for both leisure and pleasure. After 1800, the lute fell from use, the guitar was transformed into its modern form with single strings, and tablature ceased to be the preferred notation for plucked instruments.Este trabajo forma parte del proyecto de investigación “La obra musical renacentista: fundamentos, repertorios y prácticas” HAR 2015-70181-P (MINECO/FEDER, UE

Developmental Systems Theory as a Process Theory

Griffiths and Russell D. Gray (1994, 1997, 2001) have argued that the fundamental unit of analysis in developmental systems theory should be a process – the life cycle – and not a set of developmental resources and interactions between those resources. The key concepts of developmental systems theory, epigenesis and developmental dynamics, both also suggest a process view of the units of development. This chapter explores in more depth the features of developmental systems theory that favour treating processes as fundamental in biology and examines the continuity between developmental systems theory and ideas about process in the work of several major figures in early 20th century biology, most notable C.H Waddington

Biological Information, Causality and Specificity - an Intimate Relationship

In this chapter we examine the relationship between biological information, the key biological concept of specificity, and recent philosophical work on causation. We begin by showing how talk of information in the molecular biosciences grew out of efforts to understand the sources of biological specificity. We then introduce the idea of ‘causal specificity’ from recent work on causation in philosophy, and our own, information theoretic measure of causal specificity. Biological specificity, we argue, is simple the causal specificity of certain biological processes. This, we suggest, means that causal relationships in biology are ‘informational’ relationships simply when they are highly specific relationships. Biological information can be identified with the storage, transmission and exercise of biological specificity. It has been argued that causal relationships should not be regarded as informational relationship unless they are ‘arbitrary’. We argue that, whilst arbitrariness is an important feature of many causal relationships in living systems, it should not be used in this way to delimit biological information. Finally, we argue that biological specificity, and hence biological information, is not confined to nucleic acids but distributed among a wide range of entities and processes

A Developmental Systems Account of Human Nature

It is now widely accepted that a scientifically credible conception of human nature must reject the folkbiological idea of a fixed, inner essence that makes us human. We argue here that to understand human nature is to understand the plastic process of human development and the diversity it produces. Drawing on the framework of developmental systems theory and the idea of developmental niche construction we argue that human nature is not embodied in only one input to development, such as the genome, and that it should not be confined to universal or typical human characteristics. Both similarities and certain classes of differences are explained by a human developmental system that reaches well out into the 'environment'. We point to a significant overlap between our account and the ‘Life History Trait Cluster’ account of Grant Ramsey, and defend the developmental systems account against the accusation that trying to encompass developmental plasticity and human diversity leads to an unmanageably complex account of human nature

Genetic, epigenetic and exogenetic information

We describe an approach to measuring biological information where ‘information’ is understood in the sense found in Francis Crick’s foundational contributions to molecular biology. Genes contain information in this sense, but so do epigenetic factors, as many biologists have recognized. The term ‘epigenetic’ is ambiguous, and we introduce a distinction between epigenetic and exogenetic inheritance to clarify one aspect of this ambiguity. These three heredity systems play complementary roles in supplying information for development. We then consider the evolutionary significance of the three inheritance systems. Whilst the genetic inheritance system was the key innovation in the evolution of heredity, in modern organisms the three systems each play important and complementary roles in heredity and evolution. Our focus in the earlier part of the paper is on ‘proximate biology’, where information is a substantial causal factor that causes organisms to develop and causes offspring to resemble their parents. But much philosophical work has focused on information in ‘ultimate biology’. Ultimate information is a way of talking about the evolutionary design of the mechanisms of development and inheritance. We conclude by clarifying the relationship between the two. Ultimate information is not a causal factor that acts in development or heredity, but it can help to explain the evolution of proximate information, which is

Wright-Fisher diffusion bridges

{\bf Abstract} The trajectory of the frequency of an allele which begins at $x$ at time $0$ and is known to have frequency $z$ at time $T$ can be modelled by the bridge process of the Wright-Fisher diffusion. Bridges when $x=z=0$ are particularly interesting because they model the trajectory of the frequency of an allele which appears at a time, then is lost by random drift or mutation after a time $T$. The coalescent genealogy back in time of a population in a neutral Wright-Fisher diffusion process is well understood. In this paper we obtain a new interpretation of the coalescent genealogy of the population in a bridge from a time $t\in (0,T)$. In a bridge with allele frequencies of 0 at times 0 and $T$ the coalescence structure is that the population coalesces in two directions from $t$ to $0$ and $t$ to $T$ such that there is just one lineage of the allele under consideration at times $0$ and $T$. The genealogy in Wright-Fisher diffusion bridges with selection is more complex than in the neutral model, but still with the property of the population branching and coalescing in two directions from time $t\in (0,T)$. The density of the frequency of an allele at time $t$ is expressed in a way that shows coalescence in the two directions. A new algorithm for exact simulation of a neutral Wright-Fisher bridge is derived. This follows from knowing the density of the frequency in a bridge and exact simulation from the Wright-Fisher diffusion. The genealogy of the neutral Wright-Fisher bridge is also modelled by branching P\'olya urns, extending a representation in a Wright-Fisher diffusion. This is a new very interesting representation that relates Wright-Fisher bridges to classical urn models in a Bayesian setting

Non-Newtonian channel flow—exact solutions

In this short communication, exact solutions are obtained for a range of non-Newtonian flows between stationary parallel plates. The pressure-driven flow of fluids with a variational viscosity that adheres to the Carreau governing relationship are considered. Solutions are obtained for both shear-thinning (viscosity decreasing with increasing shear-rate) and shear-thickening (viscosity increasing with increasing shear-rate) flows. A discussion is presented regarding the requirements for such analytical solutions to exist. The dependence of the flow rate on the channel half width and the governing non-Newtonian parameters is also considered