EU-LIFEHAB: Expanding the discussion on the life cycles of harmful algae

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Communication: Tolman length and rigidity constants of water and their role in nucleation

A proper understanding of nucleation is crucial in several natural and industrial processes. However, accurate quantitative predictions of this phenomenon have not been possible. The most popular tool for calculating nucleation rates, classical nucleation theory (CNT), deviates by orders of magnitude from experiments for most substances. We investigate whether part of this discrepancy can be accounted for by the curvature-dependence of the surface tension. To that end, we evaluate the eading order corrections for water, the Tolman length and the rigidity constants, using square gradient theory coupled with the accurate cubic plus association equation of state. The Helfrich expansion is then used to incorporate them into the CNT-framework. For water condensation, the modified framework successfully corrects the erroneous temperature dependence of the nucleation rates given by the classical theory and reproduces experimental nucleation rates

ONGOING RESEARCH ON SPECIES OF DINOPHYSIS: ALTERNATIVES WITH UNCULTURABLE DINOFLAGELLATES

Dinophysis 200

Fractional diffusion in periodic potentials

Fractional, anomalous diffusion in space-periodic potentials is investigated. The analytical solution for the effective, fractional diffusion coefficient in an arbitrary periodic potential is obtained in closed form in terms of two quadratures. This theoretical result is corroborated by numerical simulations for different shapes of the periodic potential. Normal and fractional spreading processes are contrasted via their time evolution of the corresponding probability densities in state space. While there are distinct differences occurring at small evolution times, a re-scaling of time yields a mutual matching between the long-time behaviors of normal and fractional diffusion

Bulk and surface switching in Mn-Fe-based Prussian Blue Analogues

Many Prussian Blue Analogues are known to show a thermally induced phase transition close to room temperature and a reversible, photo-induced phase transition at low temperatures. This work reports on magnetic measurements, X-ray photoemission and Raman spectroscopy on a particular class of these molecular heterobimetallic systems, specifically on Rb0.81Mn[Fe(CN)6]0.95_1.24H2O, Rb0.97Mn[Fe(CN)6]0.98_1.03H2O and Rb0.70Cu0.22Mn0.78[Fe(CN)6]0.86_2.05H2O, to investigate these transition phenomena both in the bulk of the material and at the sample surface. Results indicate a high degree of charge transfer in the bulk, while a substantially reduced conversion is found at the sample surface, even in case of a near perfect (Rb:Mn:Fe=1:1:1) stoichiometry. Thus, the intrinsic incompleteness of the charge transfer transition in these materials is found to be primarily due to surface reconstruction. Substitution of a large fraction of charge transfer active Mn ions by charge transfer inactive Cu ions leads to a proportional conversion reduction with respect to the maximum conversion that is still stoichiometrically possible and shows the charge transfer capability of metal centers to be quite robust upon inclusion of a neighboring impurity. Additionally, a 532 nm photo-induced metastable state, reminiscent of the high temperature Fe(III)Mn(II) ground state, is found at temperatures 50-100 K. The efficiency of photo-excitation to the metastable state is found to be maximized around 90 K. The photo-induced state is observed to relax to the low temperature Fe(II)Mn(III) ground state at a temperature of approximately 123 K.Comment: 12 pages, 8 figure

Sistemas pendulares de masas múltiples y su aplicación a la extracción de energía undimotriz en el Mar Argentino

En este artículo se estudia la posibilidad de aprovechamiento de la energía undimotriz del Mar Argentino, mediante dispositivos recolectores basados en la dinámica del péndulo paramétrico. Estos dispositivos aprovechan el movimiento de las olas, empleándolo como excitación para alcanzar rotaciones de un péndulo o sistema de péndulos. Los diseños considerados involucran péndulos de múltiples masas, lo cual brinda versatilidad a los dispositivos recolectores a la hora de situarlos en determinada zona deseada del espacio de parámetros de forzamiento. A su vez, el diseño de masas múltiples es necesario desde el punto de vista práctico, con el objetivo de alcanzar la resonancia paramétrica a partir de las bajas frecuencias observadas en el oleaje oceánico. Mediante la realización de experimentos y simulaciones numéricas, se demuestra la aplicabilidad del concepto en aguas del Mar Argentino.Publicado en: Mecánica Computacional vol. XXXV, no. 26Facultad de Ingenierí

Recovering and harmonizing research cruises information

The IEO has maintained since late 60s, a local database with basic information on oceanographic campaigns, formerly known as ROSCOF reports, which were established in the framework of IODE initiatives, as a low-level inventory for future access to data. Technological advances in recent decades and different coordination activities between NODCs have favored the implementation of these reports in standardized digital formats (Cruise Summary Reports, CSR) that allow their integration in international repositories as SeaDataNet or POGO. However, this inventory and cataloging activity has suffered ups and downs over 40 years of activity, changes in storage criteria and periods of less activity. In the search for a unique criterion that can last over time and that unifies this information as much as possible with the data generated in these campaigns, an exhaustive review of the existing information has been carried out

Infrared Fluorescent Imaging as a Potent Tool for In Vitro, Ex Vivo and In Vivo Models of Visceral Leishmaniasis

Visceral leishmaniasis (VL) is hypoendemic in the Mediterranean region, where it is caused by the protozoan Leishmania infantum. An effective vaccine for humans is not yet available and the severe side-effects of the drugs in clinical use, linked to the parenteral administration route of most of them, are significant concerns of the current leishmanicidal medicines. New drugs are desperately needed to treat VL and phenotype-based High Throughput Screenings (HTS) appear to be suitable to achieve this goal in the coming years. We generated two infrared fluorescent L. infantum strains, which stably overexpress the IFP 1.4 and iRFP reporter genes and performed comparative studies of their biophotonic properties at both promastigote and amastigote stages. To improve the fluorescence emission of the selected reporter in intracellular amastigotes, we engineered distinct constructs by introducing regulatory sequences of differentially-expressed genes (A2, AMASTIN and HSP70 II). The final strain that carries the iRFP gene under the control of the L. infantum HSP70 II downstream region (DSR), was employed to perform a phenotypic screening of a collection of small molecules by using ex vivo splenocytes from infrared-infected BALB/c mice. In order to further investigate the usefulness of this infrared strain, we monitored an in vivo infection by imaging BALB/c mice in a time-course study of 20 weeks. The near-infrared fluorescent L. infantum strain represents an important step forward in bioimaging research of VL, providing a robust model of phenotypic screening suitable for HTS of small molecule collections in the mammalian parasite stage. Additionally, HSP70 II+L. infantum strain permitted for the first time to monitor an in vivo infection of VL. This finding accelerates the possibility of testing new drugs in preclinical in vivo studies, thus supporting the urgent and challenging drug discovery program against this parasitic diseaseThis research was supported by Ministerio de Economía y Competitividad (www.mineco.gob.es) grants AGL2010-16078/GAN to RBF and CYTED 214RT0482 to RMR; Instituto de Salud Carlos III (www.isciii.es) grants PI12/00104 to RMR and RICET RD12/0018/0004 to MF; Junta de Castilla y León (www.jcyl.es) grants Gr238 and LE182U13; European Commision (cordis.europa.eu/home_es.html), grant HOMIN - 317057-FP7-PEOPLE-2012-ITN and BIOIMID (http://www.fundacionareces.es) Proyecto de Excelencia Instituto Sanitario “La Princesa” and Fundación Ramón Areces to MF. SK is granted from AECC Foundation (https://www.aecc.es). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the anuscrip