Estados ecosistémicos coexistentes en una laguna costera tropical bajo eutrofización creciente en la cayería norte de Cuba

Through a nested suite of methods here we contrast the coexistence of different ecosystem states in a tropical coastal lagoon, the Laguna Larga, with increasing eutrophication stress between 2007 and 2009. Water temperature averaged 27.4°C in the lagoon and showed a slight positive trend during the study period. Salinity averaged 35.0±6.2, exhibiting high spatial and temporal variability, and also a slight positive trend in time. In contrast, dissolved oxygen showed a substantial decreasing trend (–0.83 ml L–1 y–1; –13.3% y–1) over the period, while nutrients increased dramatically, particularly total phosphorus (2.6 µM y–1), in both cases sustaining the progression of eutrophication in the lagoon during the three years we sampled. The Karydis nutrient load-based trophic index showed that the lagoon has a spatial pattern of increasing eutrophication from the sea and the outer sector (oligotrophic-mesotrophic) to the central (mesotrophic) and the inner sector (mesotrophic-eutrophic). Two ecosystem states were found within the lagoon. In the outer oligotrophic sector, the dominant primary producers were macroalgae, seagrasses and benthic diatoms, while mollusc assemblages were highly diverse. In the inner and central sectors (where trophic status increased toward the inner lagoon) a phytoplankton-dominated ecosystem was found where mollusc assemblages are less diverse. In spite of the progression of eutrophication in the lagoon, these two different ecosystems coexisted and remained unchanged during the study period. Apparently, the effect of water residence time, which increases dramatically toward the inner lagoon, dominated over that of nutrient loadings, which is relatively more homogeneously distributed along the lagoon. Therefore, we consider that actions that reduce the water residence time are likely the most effective management options for this and other similarly choked lagoons.Mediante la conjunción de una diversidad de métodos y observaciones, se contrasta la coexistencia de diferentes estados ecosistémicos en Laguna Larga, una laguna costera tropical sometida a una eutrofización creciente entre 2007 y 2009. La temperatura media en la laguna fue de 27.4°C y mostró una ligera tendencia positiva en este periodo. La salinidad mostró alta variabilidad espacial y temporal alrededor de una media de 35.0±6.2 y también tuvo una tendencia temporal positiva. En contraste, el oxígeno disuelto mostró una sustancial tendencia negativa (–0.83 ml L–1 y–1; –13.3% y–1) en el mismo periodo, al tiempo que los nutrientes se incrementaron drásticamente, en particular el fósforo total, a una tasa de 2.6 µM y–1, respaldando ambas tendencias el incremento de la eutrofización a lo largo de los tres años observados. El índice trófico de Karydis, basado en las cargas de nutrientes, mostró un patrón espacial de incremento de la eutrofización desde el mar hacia el sector exterior (oligotrófico-mesotrófico), el sector central (mesotrófico) y el sector interior (mesotrófico-eutrófico). Se identificaron dos estados ecosistémicos dentro de la laguna. En el oligotrófico sector exterior, los productores primarios dominantes fueron macroalgas, pastos marinos y diatomeas bénticas, en tanto que las asociaciones de moluscos fueron altamente diversas. En los sectores central e interior (incrementándose el estatus trófico hacia este último), se encontró un estado ecosistémico dominado por el fitoplancton y en el que las asociaciones de moluscos son menos diversas. A pesar del incremento de la eutrofización, estos dos ecosistemas distintos coexistieron y permanecieron sin cambios durante el periodo estudiado. En Laguna Larga, el efecto del tiempo de residencia del agua, que se incrementa dramáticamente hacia el interior de la laguna, domina aparentemente sobre el de la carga externa de nutrientes, que está distribuida de manera relativamente más homogénea a lo largo de la laguna. Por ello, consideramos que las acciones dirigidas a disminuir el tiempo de residencia del agua son probablemente las más efectivas en esta laguna y otras similarmente aisladas

On-site forest fire smoke detection by low-power autonomous vision sensor

Early detection plays a crucial role to prevent forest fires from spreading. Wireless vision sensor networks deployed throughout high-risk areas can perform fine-grained surveillance and thereby very early detection and precise location of forest fires. One of the fundamental requirements that need to be met at the network nodes is reliable low-power on-site image processing. It greatly simplifies the communication infrastructure of the network as only alarm signals instead of complete images are transmitted, anticipating thus a very competitive cost. As a first approximation to fulfill such a requirement, this paper reports the results achieved from field tests carried out in collaboration with the Andalusian Fire-Fighting Service (INFOCA). Two controlled burns of forest debris were realized (www.youtube.com/user/vmoteProject). Smoke was successfully detected on-site by the EyeRISTM v1.2, a general-purpose autonomous vision system, built by AnaFocus Ltd., in which a vision algorithm was programmed. No false alarm was triggered despite the significant motion other than smoke present in the scene. Finally, as a further step, we describe the preliminary laboratory results obtained from a prototype vision chip which implements, at very low energy cost, some image processing primitives oriented to environmental monitoring.Ministerio de Ciencia e Innovación 2006-TIC-2352, TEC2009-1181

On the feasibility of the computational modelling of the endoluminal vacuum-assisted closure of an oesophageal anastomotic leakage

Endoluminal vacuum-assisted closure (E-VAC) is a promising therapy to treat anastomotic leakages of the oesophagus and bowel which are associated with high morbidity and mortality rates. An open-pore polyurethane foam is introduced into the leakage cavity and connected to a device that applies a suction pressure to accelerate the closure of the defect. Computational analysis of this healing process can advance our understanding of the biomechanical mechanisms at play. To this aim, we use a dual-stage finite-element analysis in which (i) the structural problem addresses the cavity reduction caused by the suction and (ii) a new constitutive formulation models tissue healing via permanent deformations coupled to a stiffness increase. The numerical implementation in an in-house code is described and a qualitative example illustrates the basic characteristics of the model. The computational model successfully reproduces the generic closure of an anastomotic leakage cavity, supporting the hypothesis that suction pressure promotes healing by means of the aforementioned mechanisms. However, the current framework needs to be enriched with empirical data to help advance device designs and treatment guidelines. Nonetheless, this conceptual study confirms that computational analysis can reproduce E-VAC of anastomotic leakages and establishes the bases for better understanding the mechanobiology of anastomotic defect healing.Fil: Comellas, Ester. Centre Internacional de Mètodes Numèrics a l'Enginyeria; EspañaFil: Bellomo, Facundo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Rosales, Iván. B. Braun Surgical; EspañaFil: del Castillo, Luis F.. B. Braun Surgical; EspañaFil: Sánchez, Ricardo. B. Braun Surgical; EspañaFil: Turon, Pau. B. Braun Surgical; EspañaFil: Oller, Sergio Horacio Cristobal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; Argentina. Centre Internacional de Mètodes Numèrics a l'Enginyeria; España. Universidad Politécnica de Catalunya; Españ

La sistematización de resultados científicos. Una vía para el desarrollo de la Cultura Ambiental.

El artículo responde al proyecto institucional: La sistematización de resultados científicos mediante la Educación Ambiental. El desarrollo del proyecto se sustentó en las derivaciones científicas deslindadas de los proyectos de investigaciones El conocimiento de la biodiversidad de Granma mediante la divulgación ambiental; Glosario medioambiental y La crisis alimentaria: un tema de Educación Ambiental. De lo cual se derivan los análisis desarrollados en las diversas asignaturas que se imparten en las carreras de Biología-Geografía y Educación Primaria y, consecuentemente, las propuestas para materializar la infusión ambiental como proceso de integración de un determinado contenido medioambiental, sin afectar el enfoque holístico a los contenidos de los programas de asignaturas. Además se declaran las regularidades más significativas reflejadas en los talleres de sensibilización y capacitación ejecutados con los docentes de las carreras de referencia. Se utilizaron métodos del nivel empírico y teórico que permitieron derivar los resultados que se presentan

Mutation of vsx genes in zebrafish highlights the robustness of the retinal specification network

Genetic studies in human and mice have established a dual role for Vsx genes in retina development: an early function in progenitors' specification, and a later requirement for bipolar-cells fate determination. Despite their conserved expression patterns, it is currently unclear to which extent Vsx functions are also conserved across vertebrates, as mutant models are available only in mammals. To gain insight into vsx function in teleosts, we have generated vsx1 and vsx2 CRISPR/Cas9 double knockouts (vsxKO) in zebrafish. Our electrophysiological and histological analyses indicate severe visual impairment and bipolar cells depletion in vsxKO larvae, with retinal precursors being rerouted toward photoreceptor or Müller glia fates. Surprisingly, neural retina is properly specified and maintained in mutant embryos, which do not display microphthalmia. We show that although important cis-regulatory remodelling occurs in vsxKO retinas during early specification, this has little impact at a transcriptomic level. Our observations point to genetic redundancy as an important mechanism sustaining the integrity of the retinal specification network, and to Vsx genes regulatory weight varying substantially among vertebrate species

Diffusion and Monod kinetics model to determine in vivo human corneal oxygen-consumption rate during soft contact lens wear

PURPOSE: We present an analysis of the corneal oxygen consumption Qc from non-linear models, using data of oxygen partial pressure or tension (P(O2) ) obtained from in vivo estimation previously reported by other authors. (1) METHODS: Assuming that the cornea is a single homogeneous layer, the oxygen permeability through the cornea will be the same regardless of the type of lens that is available on it. The obtention of the real value of the maximum oxygen consumption rate Qc,max is very important because this parameter is directly related with the gradient pressure profile into the cornea and moreover, the real corneal oxygen consumption is influenced by both anterior and posterior oxygen fluxes. RESULTS: Our calculations give different values for the maximum oxygen consumption rate Qc,max, when different oxygen pressure values (high and low P(O2)) are considered at the interface cornea-tears film. CONCLUSION: Present results are relevant for the calculation on the partial pressure of oxygen, available at different depths into the corneal tissue behind contact lenses of different oxygen transmissibility.Del Castillo, LF.; Ferreira Da Silva, AR.; Hernández, SI.; Aguiella-Arzo, M.; Balado, A.; Mollá Romano, S.; Compañ Moreno, V. (2015). Diffusion and Monod kinetics model to determine in vivo human corneal oxygen-consumption rate during soft contact lens wear. Journal of Optometry. 8(1):12-18. doi:10.1016/j.optom.2014.06.002S12188