Minimal formulation of the linear spatial analysis of capillary jets: Validity of the two-mode approach

A rigorous and complete formulation of the linear evolution of harmonically stimulated capillary jets should include infinitely many spatial modes to account for arbitrary exit conditions [J. Guerrero et al., J. Fluid Mech. 702, 354 (2012)]. However, it is not rare to find works in which only the downstream capillary dominant mode, the sole unstable one, is retained, with amplitude determined by the jet deformation at the exit. This procedure constitutes an oversimplification, unable to handle a flow rate perturbation without jet deformation at the exit (the most usual conditions). In spite of its decaying behavior, the other capillary mode (subdominant) must be included in what can be called a “minimal linear formulation.” Deformation and mean axial velocity amplitudes at the jet exit are the two relevant parameters to simultaneously find the amplitudes of both capillary modes. Only once these amplitudes are found, the calculation of the breakup length may be eventually simplified by disregarding the subdominant mode. Simple recipes are provided for predicting the breakup length, which are checked against our own numerical simulations. The agreement is better than in previous attempts in the literature. Besides, the limits of validity of the linear formulation are explored in terms of the exit velocity amplitude, the wave number, the Weber number, and the Ohnesorge number. Including the subdominant mode extends the range of amplitudes for which the linear model gives accurate predictions, the criterion for keeping this mode being that the breakup time must be shorter than a given formula. It has been generally assumed that the shortest intact length happens for the stimulation frequency with the highest growth rate. However, we show that this correlation is not strict because the amplitude of the dominant mode has a role in the breakup process and it depends on the stimulation frequency.Ministerio de Economía, Industria y Competitividad, Spain, under Contract No. FIS2014-25161Junta de Andalucía under Contract No. P11-FQM-791

UCTx: a multi-agent system to assist a transplant coordination unit

We present a system called UCTx, designed to model and automate some of the tasks performed by a Transplant Coordination Unit (UCTx) inside a Hospital. The aim of this work is to show how a multi-agent approach allows us to describe and implement the model, and how UCTx is capable of dealing with another multi-agent (Carrel, an Agent Mediated Institution for the exchange of Human Tissues among Hospitals for Transplantation) in order to meet its own goals, acting as the representative of the hospital in the negotiation. As an example we introduce the use of this Agency in the case of Cornea Transplantation.Postprint (published version

Extending the Carrel system to mediate in the organ and tissue allocation processes: a first approach

In this paper we extend the formalization of Carrel, a virtual organization for the procurement of tissues for transplantation purposes, in order to model also the procurement of human organs for transplants. We will focus in the organ allocation process to show how it can be formalized with the ISLANDER formalism. Also we present a first mechanism to federate the institution in several geographically-distributed platforms.Postprint (published version

Searching for Biosignatures in Mars by LIBS Molecular Signals Discernment

In the present study, LIBS analysis of a set of six selected molecules related to organic biosignatures -or their degradation compounds- have been carried out in both simulated Martian atmosphere and air in order to identify and discriminate them on the basis of their molecular emission features. This strategy can reveal insights into how different emission spectral modes react to changes in atmospheric conditions and therefore can help to detect those species which are more sensitive to changes in pressure and composition of the atmosphere. At high laser irradiance, atomization of organic compounds is essentially complete, although at sufficiently delayed integration times, the formation of new molecules by recombination processes can be noticed[1]. Molecular species characteristic of organic emissions such as C2, CN, NH, OH and CH were studied. Results can contribute to establish the optimal conditions for the observation of organic carbon species in laser-induced plasmas and the bases for the ensuing detection of organic biosignatures in analogous geological materials from Mars. Likewise, this research is aimed at providing a tool in the interpretation of LIBS data though the application of adapted data processing algorithms for the identification and discernment of suspected compounds of organic nature[2] [1] T. Delgado, L. García-Gómez, L. M. Cabalín, J. J. Laserna, Investigation on the origin of molecular emissions in laser-induced breakdown spectroscopy under Mars-like atmospheric conditions of isotope-labeled compounds of interest in astrobiology, Spectrochim. Acta Part B (2021) 179-106114. [2] T. Delgado, L. García-Gómez, L. M. Cabalín, J. J. Laserna, Detectability and discrimination of biomarker organic precursors in a low pressure CO2 atmosphere by LIBS, J. Anal. At. Spectrom. (2020) 35:1947.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

La biodiversidad como herramienta en la gestión y certificación forestal : zonas de alto valor de conservación en montes madereros del suroeste peninsular

Este artículo presenta un estudio sobre la biodiversidad y el estado de ocho Zonas de Alto Valor de Conservación en la provincia de Huelva (localizada en el suroeste de la Península Ibérica), colindantes a plantaciones de especies de crecimiento rápido (Eucalyptus globulus). El estudio se incluye en el marco de un proceso de certificación forestal. Se han evaluado algunos parámetros de biodiversidad –riqueza, diversidad alfa, diversidad beta- y estado –regeneración, cobertura, densidaden 143 parcelas de comunidades leñosas. Se han registrado un alto número de taxones animales y vegetales, algunos de los cuales son especies amenazadas o endémicas. El uso de los índices de diversidad ha sido esencial; son simples abstracciones de la estructura altamente compleja de las comunidades, muy útiles para hacer comparaciones. Han mostrado la alta diversidad de las zonas estudiadas mediante datos cuantificables. Este tipo de estudios son muy importantes e útiles para conocer el estado de ecosistemas forestales y abordar su seguimiento, y por lo tanto para la gestión forestal.____________________________________This paper presents a study about the biodiversity and the status of eight Zones of High Conservation Value within the province of Huelva (located in the southwest of the Iberian Peninsula), near plantations of fast growing species (Eucalyptus globulus). The study is in the framework of a forest certification process. Some parameters of biodiversity –species richness, diversity alpha, diversity beta– and status – regeneration, cover, density– have been evaluated in 143 plots of woody communities. A high number of vegetal and animal species have been recorded; some of them are endangered or endemic species. The use of diversity indices has been essential; they are simple abstractions of the highly complex structure of communities, very useful for comparisons. They have shown the high biodiversity of the study areas using quantifiable data. Such studies are very important and useful to know the status of forest ecosystems and to address the monitoring of these ones, and therefore for forest management

Laser-induced breakdown spectroscopy of cyanobacteria in carbonate matrices under simulated Martian environment

The finding on the Martian surface of hydrated salt minerals, like carbonates and sulphates, and their interpretation as deriving from the desiccation of old bodies of water, has provided an evidence of liquid water activity on the surface of Mars [1]. These evaporite environments and their saline deposits are now a chief goal for planetary missions devoted to the search for fossil Martian life. Such minerals have the possibility of trapping and preserving over geologic times a biological record made up of halophilic extremophiles [1]. The existence of species of cyanobacteria that inhabit rock substrates on Earth, capable of growing in environments considered extreme, makes them ideal organisms for studying biological responses in different environmental conditions [2]. One possible organism detection strategy consists in the study of the most relevant emission lines and molecular bands attributed to presence of life by laser-induced breakdown spectroscopy (LIBS). However, the detection of these species can be complex as LIBS is sensitive to environmental conditions, such as the atmosphere composition and pressure, and could contribute to this signal [3]. In the present study, several species of cyanobacteria with dissimilar extremophilic characteristics [4] (tolerance to desiccation and salinity) were examined by LIBS. The identification and discrimination of cyanobacteria on carbonate substrates was based on organic signal emissions (C, C2, CN...) and the presence of other microelements (Fe, Si, Cu, K…). For this purpose, and to evaluate the influence of the surrounding atmosphere on the plasma composition and its contribution on LIBS signal, a set of samples including Arthrospira platensis (commercial), Microcystys aeruginosa (cultured) and Chroococcidiopsis sp. (natural samples) was analyzed under i) Mars-analogue atmosphere and ii) low air vacuum (7mbar)Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Gobernanza de la identidad migratoria: especificación de un modelo para el estudio del trabajo infantil

El sistema en el que se pretenden dirimir las diferencias entre dos actores históricos con respecto a un proceso de dominación social es conocido como gobernanza. Se trata de un escenario en el que la inclusión prevalece sobre la exclusión de los actores implicados. En ese sentido, la migración es un fenómeno en el que es posible observar tales asimetrías. Precisamente, el objetivo del presente trabajo es especificar un modelo para el estudio de las relaciones entre una cultura dominante y las culturas migrantes, con énfasis en la identidad y la explotación laboral infantil. Se llevó a cabo un estudio no experimental con una selección no probabilística de fuentes indexadas a repositorios líderes de América Latina, considerando el periodo de publicación de 2010 a 2016 y las palabras clave de “migración”, “identidad” y “gobernanza”. la información se procesó en matrices de análisis de contenido y se especificó en un modelo de trayectorias de las relaciones entre las variables extraídas de la revisión de la literatura. Se advierte la inclusión de la ética como factor explicativo de las diferencias entre oriundos y migrantes con respecto al ámbito laboral

An Overview of the Chemical Characteristics, Bioactivity and Achievements Regarding the Therapeutic Usage of Acetogenins from Annona cherimola Mill.

Annona cherimola Mill., or the custard apple, is one of the species belonging to the Annonaceae family, is widely used in traditional medicine, and has been reported to be a valuable source of bioactive compounds. A unique class of secondary metabolites derived from this family are Annonaceous acetogenins, lipophilic polyketides considered to be amongst the most potent antitumor compounds. This review provides an overview of the chemical diversity, isolation procedures, bioactivity, modes of application and synthetic derivatives of acetogenins from A. cherimola Mill.This work was financially supported by the 'Ministerio de Economia y Competitividad' (Project AGL2017-88083-R), Spain. F.J.R.M. thanks Universidad de Cadiz for predoctoral support under grant 2018-009/PU/EPIF-FPI-CT/CP