Pattern selection in a lattice of pulse-coupled oscillators

We study spatio-temporal pattern formation in a ring of N oscillators with inhibitory unidirectional pulselike interactions. The attractors of the dynamics are limit cycles where each oscillator fires once and only once. Since some of these limit cycles lead to the same pattern, we introduce the concept of pattern degeneracy to take it into account. Moreover, we give a qualitative estimation of the volume of the basin of attraction of each pattern by means of some probabilistic arguments and pattern degeneracy, and show how are they modified as we change the value of the coupling strength. In the limit of small coupling, our estimative formula gives a perfect agreement with numerical simulations.Comment: 7 pages, 8 figures. To be published in Physical Review

Distribució del gènere "Arthrinium" a Catalunya

An account is made of the distribution of this fungus genus in some natural substrates from Catalonia

Exploring Spirituality in Teaching Within a Christian School Context Through Collaborative Action Research

This article reports on a collaborative action research project conducted in New Zealand, during 2012, exploring spirituality in teaching within a Christian school context. The experienced primary school teacher participant chose to take action around the issue of personal fear and insecurity which were believed to be hindering professional growth and relationships. Through self-directed inquiry, critical reflective journaling, Bible study, fellowship and prayer with trusted friends, the teacher experienced a renewed sense of peace and freedom in Christ. This personal transformation was believed to be influential on subsequent professional practice, assisting the teacher to become more relational, responsive and compassionate. The findings provide a rich description of the participant’s spirituality, the lived reality of a person’s spiritual life. This report will be of interest to teachers, teacher-leaders and teacher-educators who desire to explore Christian spirituality through practitioner-led inquiry

Recensiones [Revista de Historia Económica Año IV Invierno 1986 n. 1 pp. 209-252]

Frencesco de Martino. Historia Económica de la Roma Antigua (Por Luis A. García Moreno).-- Manuel Tuñón de Lara (dir.). Textos y documentos de Historia Antigua, Media y Moderna hasta el siglo XVI (Selección de Mangas, Sayas, García Moreno, Valdeón, Salrach, Mina, Arizcun, Arié y Pérez). (Por Javier Faci).-- Manuel Martín Rodríguez. Pensamiento económico español sobre la población. De Soto a Matanegui (Por Vicente Pérez Moreda).-- P. Bairoch y A. M. Piuz (eds.). Les passages des économies traditionnelles européennes aux sociales industrielles (Por Jaume Torras Elías).-- Annales, Économies, Sociétés, Civilisations, año 39, 1984, núm. 5 (Por Gregorio Núñez Romero-Balmas).-- Josep Oliveras i Samitier. Desenvolupament industrial i evolució urbana a Manresa (1800-1870) (Por Caries Sudrià).-- Juan Antonio Vázquez García. La cuestión hullera en Asturias (1918-1935) (Por Sebastián Coll Martín).-- Ignacio Villota Elejalde. Vizcaya en la política minera española. Las asociaciones patronales, 1886-1914 (Por Mercedes Cabrera).-- José García Lasaosa: Basilio Paraíso. Industrial y político aragonés de la Restauración (Por Guillermo Cortázar).-- Bill Albert y Adrian Graves (eds.). Crisis and Change in the International Sugar Economy 1860-1914 (Por Manuel Martín Rodríguez).-- G. R. Hawke. Economía para historiadores (Por Gabriel Tortella).-- Robert William Fogel y G. R. Elton. Which Road to the Past? Two Views of History (Por Donald R. Abbott)Publicad

Synchronization, Diversity, and Topology of Networks of Integrate and Fire Oscillators

We study synchronization dynamics of a population of pulse-coupled oscillators. In particular, we focus our attention in the interplay between networks topological disorder and its synchronization features. Firstly, we analyze synchronization time $T$ in random networks, and find a scaling law which relates $T$ to networks connectivity. Then, we carry on comparing synchronization time for several other topological configurations, characterized by a different degree of randomness. The analysis shows that regular lattices perform better than any other disordered network. The fact can be understood by considering the variability in the number of links between two adjacent neighbors. This phenomenon is equivalent to have a non-random topology with a distribution of interactions and it can be removed by an adequate local normalization of the couplings.Comment: 6 pages, 8 figures, LaTeX 209, uses RevTe

Deafening silence? Marxism, international historical sociology and the spectre of Eurocentrism

Approaching the centenary of its establishment as a formal discipline, International Relations today challenges the ahistorical and aspatial frameworks advanced by the theories of earlier luminaries. Yet, despite a burgeoning body of literature built on the transdisciplinary efforts bridging International Relations and its long-separated nomothetic relatives, the new and emerging conceptual frameworks have not been able to effectively overcome the challenge posed by the ‘non-West’. The recent wave of international historical sociology has highlighted possible trajectories to problematise the myopic and unipolar conceptions of the international system; however, the question of Eurocentrism still lingers in the developing research programmes. This article interjects into the ongoing historical materialist debate in international historical sociology by: (1) conceptually and empirically challenging the rigid boundaries of the extant approaches; and (2) critically assessing the postulations of recent theorising on ‘the international’, capitalist states-system/geopolitics and uneven and combined development. While the significance of the present contributions in international historical sociology should not be understated, it is argued that the ‘Eurocentric cage’ still occupies a dominant ontological position which essentially silences ‘connected histories’ and conceals the role of inter-societal relations in the making of the modern states-system and capitalist geopolitics

Research in natural products: Amaryllidaceae ornamental plants as sources of bioactive compounds

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/12071

The impact of life tables adjusted for smoking on the socio-economic difference in net survival for laryngeal and lung cancer.

BACKGROUND: Net survival is a key measure in cancer control, but estimates for cancers that are strongly associated with smoking may be biased. General population life tables represent background mortality in net survival, but may not adequately reflect the higher mortality experienced by smokers. METHODS: Life tables adjusted for smoking were developed, and their impact on net survival and inequalities in net survival for laryngeal and lung cancers was examined. RESULTS: The 5-year net survival estimated with smoking-adjusted life tables was consistently higher than the survival estimated with unadjusted life tables: 7% higher for laryngeal cancer and 1.5% higher for lung cancer. The impact of using smoking-adjusted life tables was more pronounced in affluent patients; the deprivation gap in 5-year net survival for laryngeal cancer widened by 3%, from 11% to 14%. CONCLUSIONS: Using smoking-adjusted life tables to estimate net survival has only a small impact on the deprivation gap in survival, even when inequalities are substantial. Adjusting for the higher, smoking-related background mortality did increase the estimates of net survival for all deprivation groups, and may be more important when measuring the public health impact of differences or changes in survival, such as avoidable deaths or crude probabilities of death

A two-step mechanism for epigenetic specification of centromere identity and function

The basic determinant of chromosome inheritance, the centromere, is specified in many eukaryotes by an epigenetic mark. Using gene targeting in human cells and fission yeast, chromatin containing the centromere-specific histone H3 variant CENP-A is demonstrated to be the epigenetic mark that acts through a two-step mechanism to identify, maintain and propagate centromere function indefinitely. Initially, centromere position is replicated and maintained by chromatin assembled with the centromere-targeting domain (CATD) of CENP-A substituted into H3. Subsequently, nucleation of kinetochore assembly onto CATD-containing chromatin is shown to require either the amino- or carboxy-terminal tail of CENP-A for recruitment of inner kinetochore proteins, including stabilizing CENP-B binding to human centromeres or direct recruitment of CENP-C, respectively.National Institutes of Health grant: (GM 074150); Ludwig Institute for Cancer Research; European Molecular Biology Organization (EMBO) long-term fellowship