Bifurcations in spiral tip dynamics induced by natural convection in the Belousov–Zhabotinsky reaction

The transition to spatial-temporal complexity exhibited by spiral waves under the effect of gravitational field in the Belousov–Zhabotinsky reaction is numerically studied on the basis of spiral tip dynamics. Successive transformations in tip trajectories are characterized as a function of the hydrodynamical parameter and attributed to a Ruelle–Takens–Newhouse scenario to chaos. The analysis describes the emergence of complexity in terms of the interplay between the evolution of the velocity field and concentration waves. In particular, (i) by mapping the tip motion in relation to some hydrodynamical pseudopotentials, the general mechanism by which the velocity field affects the tip trajectory is pointed out, and, (ii) by comparing the dynamical evolutions of local and mean properties associated with the inhomogeneous structures and to the velocity field, a surprising correlation is found. The results suggest that the reaction-diffusion-convection (RDC) coupling addresses the system to some general regimes, whose nature is imposed by the hydrodynamical contribution. More generally, RDC coupling would be formalized as the phenomenon that governs the system and drives it to chaos

Energy transition for the decarbonisation of urban neighborhoods: A case study in Seville, Spain

A method of greenhouse gas inventory has been developed for evaluating the environmental implications of civilian life, in terms of carbon emission, according to citizens' behaviour and to the condition of buildings, local infrastructures and services. The assessment focuses on energy use for housing, mobility, impacts of waste and water management. All factors refer to different spatial scales, ranging from the regional, urban neighbourhood, right through to the single-family household. Based on site-specific data, carbon accounting has been performed in Seville, firstly focussing on the provincial scale, then on the urban neighbourhood of Barrio Tiro de Línea. Both quantitative information and a uniquely citizen-centred method of visual result representation have been provided and taken as a starting point for planning an energy transition and decarbonisation scenario. The graphical outcomes allow the selection of a series of carbon footprint mitigating measures to be potentially accomplished in the medium-long term. The procedure was tested during the City-Zen Roadshow, as part of the European Union FP7 City-Zen Project, and demonstrated a powerfully communicative and easily implementable method to inform policy makers and citizens, to raise awareness on real energy transition potentials and to address choices for decarbonisation

Implications of land-grabbing on the ecological balance of Brazil

In the global free-market, natural resource scarcity and opportunities for preserving the local environment are fostering international purchasing of large extensions of land, mainly for agricultural use. These land transactions often involve land cover change (i.e., through deforestation) or a shift from extensive or traditional to intensive agricultural practices. In Brazil, the land appropriation by foreign investors (i.e., the so-called "land-grabbing") is affecting natural capital availability for local communities to a different extent in the very different territorial entities. At the same time, Brazilian investors are purchasing land in other countries. Ecological footprint accounting is one appropriate lens that can be employed to visualize the aggregated effect of natural capital appropriation and use. The aim of this paper is to provide a first estimate on the effect of land-grabbing on the ecological balance of Brazil through calculating the biocapacity embodied in purchased lands in the different states of Brazil. The results show that Brazil is losing between 9 to 9.3 million global hectares (on a gross basis, or a net total of 7.7 to 8.6 million of global hectares) of its biocapacity due to land-grabbing, when considering respectively a "cropland to cropland" (i.e., no land-cover change) and a "total deforestation" scenario. This represents a minimum estimate, highlighting the need for further land-grabbing data collection at the subnational scale. This analysis can be replicated for other countries of the world, adjusting their ecological balance by considering the biocapacity embodied in international transactions of land

Disaggregating the SWOT Analysis of Marine Renewable Energies

Energy transitions require strategic plans that minimize inefficiencies and maximize energy production in a sustainable way. This aspect is fundamental in the case of innovative technologies based on marine renewable energies. Marine renewable energies involve problems and advantages which imply a reconceptualization of marine space and its management. Through an holistic SWOT analysis the main strengths, weaknesses, opportunities and threats are highlighted in this paper, considering social, economic, legal, technological, and environmental dimensions. We disaggregate the SWOT analysis for marine renewable energy technologies in order to create an overview of pros and cons for every dimension and better identify specific hotspots and possible solutions in different fields

Pollutants monitoring and air quality evaluation in a confined environment: The ‘Majesty’ of Ambrogio Lorenzetti in the St. Augustine Church in Siena (Italy)

A monitoring campaign of the levels of some organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), perfluoro alkylated substances (PFASs), chlorinated pesticides (4 isomers of hexachlorocyclohexane, hexachlorobenzene, 6 isomers and metabolites of DDT and dieldrin), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), in different matrices (dust taken from the floor and under a wall painting and fragments of the 'Majesty' wall painting by Ambrogio Lorenzetti), was conducted in the historical museum of St. Augustine's church in Siena (Italy). Instrumental analyses were made by gas chromatography and liquid chromatography coupled with mass spectrometry. The results showed the presence of some organic pollutants (PAHs and PBDEs), whose interaction with the surfaces of works of art are not yet fully elucidated. The study was complemented by monitoring the air quality inside and outside the church for the detection of volatile organic compounds (VOCs); all the results showed low levels of air pollution. Copyright (C)2016 Turkish National Committee for Air Pollution Research and Control

Relating pain intensity of newborns to onset of nonlinear phenomena in cry recordings

The cries of several full term newborns, recorded during blood sampling, were analyzed. Spectrograms showed the appearance of irregular patterns related to the pain assessed using the method of the DAN scale. In particular, the appearance of Noise concentration Patterns (NP) in spectrograms was related to the increase of the pain suffered by the newborns. In this scenario, pain constitutes a bifurcation parameter for the vocal folds dynamic, inducing a Ruelle-Takens-Newhouse chaotic transition.Comment: 15 pages, 4 figures, 1 table. Accepted for publication in Phys. Lett.

Ruelle–Takens–Newhouse scenario in reaction-diffusion-convection system

Direct numerical simulations of the transition process from periodic to chaotic dynamics are presented for two variable Oregonator-diffusion model coupled with convection. Numerical solutions to the corresponding reaction-diffusion-convection system of equations show that natural convection can change in a qualitative way, the evolution of concentration distribution, as compared with convectionless conditions. The numerical experiments reveal distinct bifurcations as the Grashof number is increased. A transition to chaos similar to Ruelle-Takens-Newhouse scenario is observed. Numerical results are in agreement with the experiments