Development of new remediation technologies for contaminated soils based on the application of zero-valent iron nanoparticles and bioremediation with compost

This study aimed to develop new techniques for the remediation of contaminated soils based on the applicationof zero-valent iron nanoparticles (nZVI) and bioremediation with compost from organic wastesand a mixed technique of both. An assessment of the effectiveness of remediation in two soils contaminatedwith hydrocarbons and heavy metals was carried out, with the aim of looking for positive synergiesby combining the two techniques, and demonstrating their viability on an industrial scale. The applicationof nZVI for in situ immobilization of As and Cr in two different soils (Soil I from a contaminatedindustrial site and Soil II, contaminated artificially) showed a decrease in the concentration of As in SoilI and Soil II, as well as a decrease in Cr concentration for Soil I and Soil II in the leachate of both soils.The addition of compost and nanoparticles under uncontrolled environmental conditions in biopiles wasable to produce a decrease in the concentration of aliphatic hydrocarbons of up to 60% in the two soils.Especially, degradation and transformation of longer chains occurred. A significant reduction of ecotoxicitywas observed throughout the process in the biopile of soil II, not reaching the LC50 even with 100%of the sample after the treatment, in both earthworm and seeds growth tests

Levaduras autóctonas como factores de crecimiento en Rhamdia quelen: primeras aproximaciones

Rhamdia quelen is an autochthonous fish used for aquaculture in the Northeast of Argentina. Antibiotics as growing factors in fish production had been criticized in the last years and the use of microorganisms emerged as a putative replacement. The aim of this study was to isolate autochthonous yeasts from R. quelen and to evaluate the effect of the administration over biometrical parameters of larvae under intensive culture system. Fungi were isolated from the digestive tract of wild specimens, phenotypically identified and evaluated on their ability to exert beneficial properties. One selected fungal isolate was administered, four times a day, dead or alive at 1 or 2% together with balanced feed to R. quelen larvae for 15 days. aftertreatment larvae were counted and weighted in order to obtain the values of survival, mean weight and total biomass. Only four Candida tropicalis isolates were obtained. None of them expressed beneficial properties. One fungal isolate was randomly selected for in vivo assays. Results indicated that only dead yeast at 1% induced a significant increment of biomass when compared with the control group (p<0.05). Survival rate was boosted significantly (p<0.05) with dead yeast and not significantly (p>0.05) with the fungal isolate. None of the treatments induced significant increments in mean weight (p<0.05). These results allowed us to propose  the treatment with dead yeast at 1% as a growing factor for R. quelen, considering this microorganism as an effective prebiotic in the aquaculture of this specie.Rhamdia quelen es un pez autóctono cultivado en el nordeste argentino. El uso de antibióticos como factores de crecimiento en acuicultura fue criticado en los últimos años y la administración de microorganismos surgió como una opción posible. El objetivo de este trabajo fue aislar levaduras autóctonas de R. quelen y evaluar el efecto de su administración sobre parámetros biométricos de larvas en cultivo intensivo. Los hongos se aislaron del tracto digestivo de especímenes de vida silvestre, se identificaron fenotípicamente y se evaluaron en cuanto a la expresión de propiedades benéficas. Se seleccionó una de las cepas y se administró cuatro veces por día, muerta o viva al 1 o 2% junto con el alimento balanceado durante 15 días. Luego del tratamiento las larvas se contaron y pesaron para obtener los valores de sobrevida, peso medio y biomasa. Sólo se obtuvieron cuatro aislamientos de Candida tropicalis. Ninguno expresó propiedades benéficas y uno fue elegido al azar para los ensayos in vivo. Solo la levadura muerta al 1% incrementó significativamente la biomasa en comparación con el control (p<0,05). La sobrevida mejoró significativamente (p<0,05) con la levadura muerta y sin significancia (p>0,05) con el hongo vivo. Ninguno de los tratamientos induce incrementos significativos del peso medio (p<0,05). Estos resultados nos permiten proponer al tratamiento con levadura muerta al 1% como un factor de crecimiento para R. quelen, considerando al microorganismo como un prebiótico efectivo para su uso en esta especie

Segundo informe del Observatorio de Costes y Financiación del Transporte Urbano Colectivo: encuesta a los gestores

A comienzos de 2012 se publicó el Primer Informe del Observatorio de Costes y Financiación del Transporte Urbano Colectivo (OTUC), creado con el apoyo y colaboración de la Asociación de Empresas del Transporte Urbano Colectivo (ATUC) que ha facilitado la adhesión de las principales empresas representantes del sector analizado, con el objetivo fundamental de estudiar las condiciones de explotación de las empresas de transporte urbano colectivo en superficie en España. Consolidado el proyecto iniciado por el Observatorio, en septiembre de 2013 se publica su Segundo Informe, en el que, como se realizó en el primero, y al objeto de conocer la visión de los gestores y la valoración que otorgan a los principales puntos críticos del negocio, se desarrolló una encuesta cuyos resultados se muestran en el presente trabajo.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Neurorrestauración tras la isquemia cerebral: papel de los neurotransmisores en la neurogénesis postisquémica

Introduction. Brain ischemia and reperfusion produce alterations in the microenvironment of the parenchyma, including ATP depletion, ionic homeostasis alterations, inflammation, release of multiple cytokines and abnormal release of neurotransmitters. As a consequence, the induction of proliferation and migration of neural stem cells towards the peri-infarct region occurs. Development. The success of new neurorestorative treatments for damaged brain implies the need to know, with greater accuracy, the mechanisms in charge of regulating adult neurogenesis, both under physiological and pathological conditions. Recent evidence demonstrates that many neurotransmitters, glutamate in particular, control the subventricular zone, thus being part of the complex signalling network that influences the production of new neurons. Conclusion. Neurotransmitters provide a link between brain activity and subventricular zone neurogenesis. Therefore, a deeper knowledge of the role of neurotransmitters systems, such as glutamate and its transporters, in adult neurogenesis, may provide a valuable tool to be used as a neurorestorative therapy in this pathology.Peer Reviewe

IMF - metallicity: a tight local relation revealed by the CALIFA survey

Variations in the stellar initial mass function (IMF) have been invoked to explain the spectroscopic and dynamical properties of early-type galaxies. However, no observations have yet been able to disentangle the physical driver. We analyse here a sample of 24 early-type galaxies drawn from the CALIFA survey, deriving in a homogeneous way their stellar population and kinematic properties. We find that the local IMF is tightly related to the local metallicity, becoming more bottom-heavy towards metal-rich populations. Our result, combined with the galaxy mass-metallicity relation, naturally explains previous claims of a galaxy mass-IMF relation, derived from non-IFU spectra. If we assume that - within the star formation environment of early-type galaxies - metallicity is the main driver of IMF variations, a significant revision of the interpretation of galaxy evolution observables is necessary.Comment: Accepted for publication in ApJL. 6 pages, 4 figure

First survey of Wolf-Rayet star populations over the full extension of nearby galaxies observed with CALIFA

The search of extragalactic regions with conspicuous presence of Wolf-Rayet (WR) stars outside the Local Group is challenging task due to the difficulties in detecting their faint spectral features. In this exploratory work, we develop a methodology to perform an automated search of WR signatures through a pixel-by-pixel analysis of integral field spectroscopy (IFS) data belonging to the Calar Alto Legacy Integral Field Area survey, CALIFA. This technique allowed us to build the first catalogue of Wolf-Rayet rich regions with spatially-resolved information, allowing to study the properties of these complexes in a 2D context. The detection technique is based on the identification of the blue WR bump (around He II 4686 {\AA}, mainly associated to nitrogen-rich WR stars, WN) and the red WR bump (around C IV 5808 {\AA} and associated to carbon-rich WR stars, WC) using a pixel-by-pixel analysis. We identified 44 WR-rich regions with blue bumps distributed in 25 galaxies of a total of 558. The red WR bump was identified only in 5 of those regions. We found that the majority of the galaxies hosting WR populations in our sample are involved in some kind of interaction process. Half of the host galaxies share some properties with gamma-ray burst (GRB) hosts where WR stars, as potential candidates to being the progenitors of GRBs, are found. We also compared the WR properties derived from the CALIFA data with stellar population synthesis models, and confirm that simple star models are generally not able to reproduce the observations. We conclude that other effects, such as the binary star channel (which could extend the WR phase up to 10 Myr), fast rotation or other physical processes that causes the loss of observed Lyman continuum photons, are very likely affecting the derived WR properties, and hence should be considered when modelling the evolution of massive stars.Comment: 33 pages, accepted for publication in A&

Reliability of 4-m and 6-m walking speed tests in elderly people with cognitive impairment

[Abstract] The purpose of this study was to evaluate the interrater and test–retest reliability of 4-m and 6-m walking speed tests in elderly people with cognitive impairment. 50 subjects aged 65 and over with cognitive impairment were selected from an adult day-care centre and a nursing home. To examine interrater reliability, 21 people were evaluated independently by two researchers who administered the 4-m and 6-m walking tests in each evaluation. For test–retest reliability, two observers administered the tests to the same 29 subjects, with a time interval of one week. Intraclass correlation coefficients (ICCs) were calculated to examine interrater and test–retest reliability. The ICCs for interrater reliability reached values of 0.96 and 0.88 for the 4-m and 6-m walking tests, respectively. In the test–retest study, the time interval was 7.4 1.17 days. The ICCs were 0.91 for the 4-m test and 0.86 for the 6-m test. The results support the use of walking tests in elderly people with cognitive impairment