Temporal and Density Flow in Javanese Gamelan

This chapter discusses the concept of irama: the articulation and changing of temporal and density flow in Javanese gamelan that would guide and inspire musicians to render melody and rhythm in all sorts of variations. The chapter begins with a brief history of the development of gamelan theory. The main discussion of the chapter is on cross-cultural elucidation of irama by Indonesian and Western theorists. Beyond its technical and mechanical significance, the heart of irama is its impact on the melody and rhythm of gendhing (composition). The changing of irama, led by kendhang (drum), inspires musicians to elaborate, embellish, or simplify their melodies, resulting in ensemble’s togetherness, though not in a perfect synchrony. The drumming itself also affected by the irama, as the drummer selects the style of drumming accordingly. The chapter ends with listening guides to a number of compositions based on irama and textural and timbral changes.

Ionic Imbalances and Coupling in Synchronization of Responses in Neurons

Most neurodegenerative diseases (NDD) are a result of changes in the chemical composition of neurons. For example, Alzheimer’s disease (AD) is the product of Aβ peptide deposition which results in changes in the ion concentration. These changes in ion concentration affect the responses of the neuron to stimuli and often result in inducing excessive excitation or inhibition. This paper investigates the dynamics of a single neuron as ion changes occur. These changes are incorporated using the Nernst equation. Within the central and peripheral nervous system, signals and hence rhythms, are propagated through the coupling of the neurons. It was found that under certain conditions the coupling strength between two neurons could mitigate changes in ion concentration. By defining the state of perfect synchrony, it was shown that the effect of ion imbalance in coupled neurons was reduced while in uncoupled neurons these changes had a more significant impact on the neuronal behavior.

Fenologia de uma espécie arbórea em ecótono Caatinga / Cerrado no sul do Piauí

<p>O objetivo deste trabalho foi caracterizar a fenologia de uma população natural de <em>Terminalia fagifolia</em> Mart, localizada em ecótono entre os Biomas Cerrado e Caatinga, no município de Bom Jesus, sul do Estado do Piauí. Vinte indivíduos, com distância mínima de 20 metros entre si, foram marcados, utilizando GPS. Os dados fenológicos foram coletados durante um ano e as fenofases observadas foram brotação, desfolhamento, floração e frutificação. Para análise dos dados foram utilizados índices de atividade, intensidade e sincronia, além da correlação de Spearman que avaliou dados fenológicos em conjunto com variáveis ambientais. A análise fenológica indicou presença de todas as fenofases durante o período de estudos, sendo o desfolhamento observado continuamente, variando apenas em seu grau de intensidade. A população estudada apresentou sincronia perfeita entre os indivíduos nas fenofases desfolhamento e brotação. Quanto à correlação de Spearman, os resultados não indicaram correlações significativas entre fenofases e variáveis ambientais.</p><p align="center"><strong><em>Phenology of tree species in Caatinga / Cerrado boundary in southern Piaui</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The aim this work was to characterize the phenology of <em>Terminalia fagifolia</em> Mart. in a Cerrado/Caatinga boundary , in Bom Jesus, Piauí, Brazil. Twenty individuals were marked using GPS. The phenological study was conducted for 1 year and were observed the phenophases sprouting, leaf loss, flowering and fruiting. For analysis of phenological data were used the index of activity, the synchronism index and correlation of Spearman. The phenological analysis indicated the presence of all phenophases during the study period, with defoliation observed continuously, varying only in their degree of intensity. The study population had a perfect synchrony between individuals to defoliation and sprouting. Regarding the Spearman correlation the results did not indicate significant correlations between phenophases and environmental variables.</p>

Five fundamental constraints on theories of the origins of music

The diverse forms and functions of human music place obstacles in the way of an evolutionary reconstruction of its origins. In the absence of any obvious homologues of human music among our closest primate relatives, theorizing about its origins, in order to make progress, needs constraints from the nature of music, the capacities it engages, and the contexts in which it occurs. Here we propose and examine five fundamental constraints that bear on theories of how music and some of its features may have originated. First, cultural transmission, bringing the formal powers of cultural as contrasted with Darwinian evolution to bear on its contents. Second, generativity, i.e. the fact that music generates infinite pattern diversity by finite means. Third, vocal production learning, without which there can be no human singing. Fourth, entrainment with perfect synchrony, without which there is neither rhythmic ensemble music nor rhythmic dancing to music. And fifth, the universal propensity of humans to gather occasionally to sing and dance together in a group, which suggests a motivational basis endemic to our biology. We end by considering the evolutionary context within which these constraints had to be met in the genesis of human musicality.

Cellular Automata Communication Models

In this paper, cellular automata (CA) are viewed as an abstract model for distributed computing. The author argues that the classical CA model must be modified in several important respects to become a relevant model for large-scale MAS. The paper first proposes sequential cellular automata (SCA) and formalizes deterministic and nondeterministic versions of SCA. The author then analyzes differences in possible dynamics between classical parallel CA and various SCA models. The analysis in this paper focuses on one-dimensional parallel and sequential CA with node update rules restricted to simple threshold functions, as arguably the simplest totalistic, yet non-linear (and non-affine) update rules. The author identifies properties of asymptotic dynamics that can be proven to be entirely due to the assumption of perfect synchrony in classical, parallel CA. Finally, the paper discusses what an appropriate CA-based abstraction would be for large-scale distributed computing, insofar as the inter-agent communication models. In that context, the author proposes genuinely asynchronous CA and discusses main differences between genuinely asynchronous CA and various weakly asynchronous sequential CA models found in the literature.

Antiphonal four-part synchronized chorusing in a Neotropical wren

Plain-tailed wrens ( Thryothorus euophrys ) live in groups that sing synchronized choruses, the contributions of females and males alternating with each other in cycles, within which each sex sings two of the four parts, the whole achieving near perfect synchrony. As each bird has a repertoire of ca 20 phrases of each type, the synchrony also requires them to choose the same type at the same time as others of their sex. Songs can last up to 2 min, during which individuals join in and drop out. This must be one of the most complex singing performances yet described in a non-human animal.

Slow Switching and Broken Cluster State in a Population of Neuronal Oscillators

We discuss a novel class of cluster states in globally coupled neuronal oscillators. It is well known that steady cluster states such as perfect synchrony and multi-cluster states arise in globally coupled oscillators. However, little has been discussed on unsteady cluster states which often arise in populations of neuronal oscillators. We show three types of unsteady cluster states, i.e. a pair of clusters involving slow switching, three clusters involving slow switching, and a broken single cluster. These states result from saddle connections between different cluster states, and typically arise near a bifurcation point where perfect synchrony loses its stability.

UNMASKING A MODULATED CHAOTIC COMMUNICATIONS SCHEME

This paper will address the problem of unmasking a new chaotic communication scheme using synchronizing circuits, where the Lorenz system is modulated by the message and the x-coordinate of the modulated system is added to the message and transmitted to the receiver. The receiver is driven into perfect synchrony with the transmitter even in the presence of the message, and since the message becomes part of the dynamics it provides very little distortion to the phase space of the dynamical system. However, this paper will demonstrate that it is still possible to extract a sinusoidal message from the transmitted signal. It will also be shown that it is possible to extract the sinusoidal signal solely from the x-coordinate, without secondarily adding back the message sinusoid before transmission. The message extraction is also shown to work for simple frequency-modulated and phase-modulated message signals. The modulated communication scheme does effectively nullify a multi-step unmasking technique which had been somewhat successful when applied to chaotic communication schemes which employed additive message signals.

Variation in Flowering Parameters Within and Among Five Species of Australian Alpine Ranunculus

The flowering phenology of the perennial herbs Ranunculus muelleri, R. dissectifolius, R. granticola, R. millanii and R. niphophilus were characterised at two sites over two flowering seasons in the Kosciusko alpine region of Australia. The date a plant started flowering (mean values for species ranged from 8 November to 14 December), the duration of flowering (mean values for species ranged from 14.3 days to 35.1 days), asynchrony of flower production (mean values ranged from 1.38 to 10.4 days), asynchrony of first day of flowering (mean values ranged from 4.61 to 8.13), intraspecific synchrony (mean values ranged from 0.53 to 0.73, where a value of 1 equals perfect synchrony), and number of flowers (mean values ranged from 1.9 to 10.7) all differed between sites and flowering seasons within species, and among the five species. Thus, while temporal and spatial variation in flowering parameters within species occurred, it did not mask variation among species, with each of the five species of Ranunculus having a distinct flowering pattern.