New classes of stable exact solutions for a nonlinear rotational DNA model

We consider a system of two coupled nonlinear partial differential equations for describing the rotational motions of bases in both polynucleotide chains of the DNA molecule. The model was proposed by L.V. Yakushevich and it is well known that the model supports, for some operating regimes, traveling wave solutions as kink–(antikink) soliton solutions. We have tried to make some progress by performing an analysis of the classical symmetries of this model. Our study shows that the model does not have enough symmetries as to reduce the equations to ordinary differential equations. Nevertheless, the known symmetries have been useful for finding several classes of exact solutions, by imposing adequate Ansätze. Some of them are kink–(antikink) like solutions, but other ones are not traveling wave solutions. For some of the new solutions, we have carried out a qualitative study and analyzed some stability properties. We think that they could be significant for the description of the DNA molecule as well as for some other applications.DGYCYT project MTM2006-05031Junta de Andalucía FQM 201. P06-FQM-0144

Low-intensity acoustic waves detection using an interferometer

We present a device built in fiber optic capable of detecting acoustic signals in water, using a buzzer as the vibration source, this buzzer operates at a frequency range from 3 kHz to 30 kHz. This device operates under the principle of a Sagnac interferometer, where the acoustic waves emitted by the buzzer are detected as a phase modulation in the monitored signal. The measured phase is due to strain experienced by the fiber optic which is caused by the vibrations emitted by the buzzer. The device can detect signals up to 7 cm away from the acoustic source

Fracturas de antebrazo: resultado funcional tras reducción abierta y osteosíntesis

Hemos realizado una revisión retrospectiva de pacientes intervenidos por fracturas de antebrazo, recogiendo el resultado funcional (Grace-Eversmann). También hemos analizado la deformidad radial residual mediante el cálculo curvatura mayor del radio (CMR). Se cálculo el coeficiente de correlación de Pearson entre la CMR y el resultado funcional. Los resultados de 20 pacientes intervenidos entre 1972 y 2005. El tratamiento quirúrgico fue de reducción abierta y fijación interna (RAFI) en el 70%. El resultado funcional fue de excelente el 50% y malo en el 20%. La curvatura mayor del radio oscilaba entre 5 mm - 20 mm. No hemos observado correlación entre las variables estudiadas. No hemos observado correlación anatómico-funcional en los pacientes tratados quirúrgicamente por fractura de cubito y radio.Retrospective review of clinical notes. Data regarding to the surgical treatments. Functional outcomes (Grace-Eversmann). Residual radius deformity was analyzed measuring the radius curvature. Pearson's correlation coefficient was measured between radius curvature and functional outcome. Data of 20 patients attended between 1972 and 2005 are reviewed. Surgical treatment was open reduction and internal fíxation in 70% patients. The outcome was excellent in 50 % and poor in 20%. La major curve of the radius was between 5mm -20 mm. We haven't seen correlation in the variables studied. We haven't seen between the curvature of the radius and functional outcome any correlation in patients treated surgically of ulna and radius fractures

Spatiotemporal determinants of seasonal gleaning

1. Many coastal communities depend on ecosystems for goods and services that contribute to human well-being. As long-standing interactions between people and nature are modified by global environmental change, dynamic and diversified livelihood strategies that enable seasonal adaptation will be critical for vulnerable coastal communities. However, the success of such strategies depends on a range of poorly understood influences. 2. Gleaning, the hand-based collection of marine organisms from littoral habitats, provides an interesting case study of dynamic change in social-ecological interac- tions. It is an important coastal livelihood strategy, yet seasonal gleaning dynamics have not been empirically explored in contemporary communities. We examined seasonal gleaning in eight coastal communities on Atauro Island, Timor-Leste, using household surveys and satellite-derived maps of shallow-water benthic habitats. Our analysis explored the factors affecting household decisions to glean in each season, the relationship between gleaning and seafood consumption, and seasonal gleaning pressure on near-shore coastal resources. 3. Dynamic marine harvesting strategies differed among households and gleaning activity was seasonally heterogeneous. Not all gleaning households gleaned dur- ing the season characterised by rough sea conditions despite rough season glean- ing being associated with greater seafood consumption stability among seasons. Households also gleaned less regularly, and catches were smaller, in the rough season. 4. Differences in seasonal participation in gleaning were explained mostly by type and extent of shallow habitat proximate to a community. In the calm season, household gleaning was positively related to the total area of shallow habitat, and in the rough season the percentage of hard-bottom shallow habitat was also an important predictor of gleaning activity. 5.Our findings illustrate how changes in the biophysical environment mediate human–nature interactions at fine scales through time and space. Consequently, this research highlights the importance of context-specific perspectives for under- standing drivers and dynamics in fishing pressure on littoral ecosystems, access to ecosystem benefits and limits to adaptation. Factors influencing when livelihood activities are feasible and desirable are important for evaluating the social impacts of climate change, particularly in the context of rural communities in the Global South

Effect of the Introduction of Impurities on the Stability Properties of Multibreathers at Low Coupling

sing a theorem dubbed the {\em Multibreather Stabiliy Theorem} [Physica D 180 (2003) 235-255] we have obtained the stability properties of multibreathers in systems of coupled oscillators with on-site potentials, with an inhomogeneity. Analytical results are obtained for 2-site, 3-site breathers, multibreathers, phonobreathers and dark breathers. The inhomogeneity is considered both at the on-site potential and at the coupling terms. All the results have been checked numerically with excellent agreement. The main conclusion is that the introduction of a impurity does not alter the stability properties.Comment: 20 pages, 9 figure

Nuclear data requirements for the ADS conceptual design EFIT: Uncertainty and sensitivity study

In this paper, we assess the impact of activation cross-section uncertainties on relevant fuel cycle parameters for a conceptual design of a modular European Facility for Industrial Transmutation (EFIT) with a “double strata” fuel cycle. Next, the nuclear data requirements are evaluated so that the parameters can meet the assigned design target accuracies. Different discharge burn-up levels are considered: a low burn-up, corresponding to the equilibrium cycle, and a high burn-up level, simulating the effects on the fuel of the multi-recycling scenario. In order to perform this study, we propose a methodology in two steps. Firstly, we compute the uncertainties on the system parameters by using a Monte Carlo simulation, as it is considered the most reliable approach to address this problem. Secondly, the analysis of the results is performed by a sensitivity technique, in order to identify the relevant reaction channels and prioritize the data improvement needs. Cross-section uncertainties are taken from the EAF-2007/UN library since it includes data for all the actinides potentially present in the irradiated fuel. Relevant uncertainties in some of the fuel cycle parameters have been obtained, and we conclude with recommendations for future nuclear data measurement programs, beyond the specific results obtained with the present nuclear data files and the limited available covariance information. A comparison with the uncertainty and accuracy analysis recently published by the WPEC-Subgroup26 of the OECD using BOLNA covariance matrices is performed. Despite the differences in the transmuter reactor used for the analysis, some conclusions obtained by Subgroup26 are qualitatively corroborated, and improvements for additional cross sections are suggested

Nanostructure of Thin Films Grown by Deposition of Isotropically Distributed Gaseous Particles

: Presentación en la conferencia “12th International Conference on Plasma Surface Engineering”Peer reviewe