Galactic chemical evolution: Stellar yields and the initial mass function

We present a set of 144 Galactic chemical evolution models applied to a Milky Way analogue, computed using four sets of low+intermediate star nucleosynthetic yields, six massive star yield compilations, and six functional forms for the initial mass function. A comparison is made between a grid of multiphase chemical evolution models computed with these yield combinations and empirical data drawn from the Milky Way's disc, including the solar neighbourhood. By means of a χ2 methodology, applied to the results of these multiphase models, the best combination of stellar yields and initial mass function capable of reproducing these observations is identified

Evolución de galaxias enanas aisladas

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Teórica. Fecha de lectura: 18-04-0

Nature or nurture? Clues from the distribution of specific star formation rates in SDSS galaxies

This work investigates the main mechanism(s) that regulate the specific star formation rate (SSFR) in nearby galaxies, cross-correlating two proxies of this quantity -- the equivalent width of the \Ha\ line and the $(u-r)$ colour -- with other physical properties (mass, metallicity, environment, morphology, and the presence of close companions) in a sample of $\sim82500$ galaxies extracted from the Sloan Digital Sky Survey (SDSS). The existence of a relatively tight `ageing sequence' in the colour-equivalent width plane favours a scenario where the secular conversion of gas into stars (i.e. `nature') is the main physical driver of the instantaneous SSFR and the gradual transition from a `chemically primitive' (metal-poor and intensely star-forming) state to a `chemically evolved' (metal-rich and passively evolving) system. Nevertheless, environmental factors (i.e. `nurture') are also important. In the field, galaxies may be temporarily affected by discrete `quenching' and `rejuvenation' episodes, but such events show little statistical significance in a probabilistic sense, and we find no evidence that galaxy interactions are, on average, a dominant driver of star formation. Although visually classified mergers tend to display systematically higher EW(H$\alpha$) and bluer $(u-r)$ colours for a given luminosity, most galaxies with high SSFR have uncertain morphologies, which could be due to either internal or external processes. Field galaxies of early and late morphological types are consistent with the gradual `ageing' scenario, with no obvious signatures of a sudden decrease in their SSFR. In contrast, star formation is significantly reduced and sometimes completely quenched on a short time scale in dense environments, where many objects are found on a `quenched sequence' in the colour-equivalent width plane.Comment: 18 pages, 9 figure

Äreas Vaginais: função terapéutica

Introducción: Las esferas vaginales también son conocidas como bolas chinas, bolas vaginales, bolas del amor, bolas de geisha, Rin no tama, bolas Ben Wa. Ayudan a fortalecer el suelo pélvico. Estas producen una microvibración al moverse la bola del interior, favoreciendo la musculatura del suelo pélvico y aumentando el riego sanguíneo a nivel de la pelvis. Hay esferas de diferente peso, par su indicación el suelo pélvico debe estar tónico. Objetivo: Revisar la literatura sobre la efectividad de las esferas vaginales e incrementar los conocimientos de los profesionales sobre este tipo de tratamiento propioceptivo, que resulta eficaz para muchas mujeres por su fácil utilización. Metodología: Búsqueda bibliográfica en las bases de datos: Cochrane Plus, Medline, Gerion, Scielo, Cuiden, Biblioteca de Salud Reproductiva de la OMS y google académico. Resultados: Las esferas vaginales son eficaces en el tratamiento de la incontinencia urinaria y fecal y para el entrenamiento del suelo pélvico. La incontinencia urinaria es un problema frecuente y molesto, que puede llegar a interferir en el trabajo, en la vida social y sexual. Hay necesidad de más ensayos para evaluar los métodos y protocolos de entrenamiento adecuados para la prevención de la incontinencia, del prolapso y de la disfunción sexual. Conclusión: Se ha evidenciado que las esferas vaginales son eficaces en el tratamiento de mujeres con incontinencia urinaria de esfuerzo e igualmente efectivas, en el entrenamiento muscular del suelo pélvico.Introduction: Vaginal spheres are also known as Chinese balls, vaginal balls, love balls, geisha balls, Rin no tama, Ben Wa balls. Help strengthen the pelvic floor. These produce a microvibration to move the ball inside, favoring the pelvic floor muscles and increasing blood flow to the pelvic region. There are different areas of weight, torque indications pelvic floor should be tonic. Objective: To review the literature on the effectiveness of vaginal balls and increase knowledge of the professionals on this kind of proprioceptive therapy, which is effective for many women for its easy use. Methods: Literature search in databases: Cochrane, Medline, Gerion, SciELO, Take care, Reproductive Health Library WHO and Academic Google. Results: The vaginal balls are effective in the treatment of urinary and fecal incontinence and pelvic floor training. Urinary incontinence is a common and distressing problem, which may interfere in the work, social and sexual life. There is need for further trials to evaluate the methods and protocols of adequate training for the prevention of incontinence, prolapse and sexual dysfunction. Conclusion: It has been shown that vaginal are better than no active treatment in women with stress urinary incontinence and can be equally effective than pelvic floor muscle training and electrical stimulation.Introdução: áreas vaginais são também conhecidos como bolas chinesas, bolas vaginais, bolas de amor, bolas de geisha, Rin no tama, bolas Ben Wa. Ajude a fortalecer o assoalho pélvico. Estes produzem um micro-vibrações para mover a bola para dentro, favorecendo os músculos do assoalho pélvico e aumentando o fluxo de sangue para a região pélvica. Existem diferentes áreas do peso, as indicações de torque assoalho pélvico deve ser tônica. Objetivo: Revisar a literatura sobre a eficácia das áreas vaginal e aumentar o conhecimento dos profissionais sobre este tipo de terapia proprioceptiva, que é eficaz para muitas mulheres para a sua fácil utilização. Métodos: Pesquisa bibliográfica em bases de dados: Cochrane, Medline, Gerion, SciELO, tome cuidado, Biblioteca de Saúde Reprodutiva da OMS e acadêmico google. Resultados: As esferas vaginais são eficazes no tratamento da incontinência urinária e fecal e treinamento do assoalho pélvico. A incontinência urinária é um problema comum e angustiante, que pode interferir no trabalho, na vida social e sexual. Há necessidade de novos estudos para avaliar os métodos e protocolos de treinamento adequado para a prevenção de incontinencia urinária, prolapso e disfunção sexual. Conclusão: Tem sido demonstrado que as áreas vaginal são eficazes no tratamento de mulheres igualmente eficaz na formação da musculatura do pavimento pélvico e incontinência urinária

Assessment of a wide array of contaminants of emerging concern in a Mediterranean water basin (Guadalhorce river, Spain): Motivations for an improvement of water management and pollutants surveillance

This study investigates the occurrence and distribution of 185 organic contaminants (regulated pollutants and contaminants of emerging concern; CECs) in surface and groundwater of the Guadalhorce River basin (southern Spain) providing the most detailed dataset regarding organic pollution presented so far in this area. Up to 63 contaminants were detected in a monitoring campaign conducted in March 2016. Most contaminants were detected more frequently in surface water where they generally present higher concentrations suggesting the prevalence of wastewater discharges into streams as the main pollutant sources. In general, hydrophobic CECs presented the highest frequencies of detection and concentrations, which can be a consequence of several factors: (1) hydrophobic compounds show a higher retardation factor, which result, along with a continuous contaminant input, in a widespread and homogeneous distribution. In contrast, hydrophilic contaminants are more easily transported by water flows towards the lower basin and potentially accumulate as driven by groundwater flow and because of low renewal rates in the detrital aquifers caused by re-pumping and irrigation return flows in agricultural lands; (2) hydrophobic CECs studied in this research are mainly personal care products and organophosphate esters flame retardants and plasticizers, which are present in many different products and are used in large amounts; Also, (3) use of biosolids (reclaimed sewer sludge) as fertilizer for crops is potentially an additional diffuse source of organic pollutants in the study area contributing to a widespread distribution, especially for hydrophobic compounds. Obtained results highlight the need to better define the potential risk of non-regulated contaminants in water resources as well as the great impact of untreated wastewater discharges

Screening and Distribution of Contaminants of Emerging Concern and Regulated Organic Pollutants in the Heavily Modified Guadalhorce River Basin, Southern Spain

Emerging pollutants have aroused an increasing concern due to their ubiquitous presence in the environment and harmful potential. Both emerging (e.g., pharmaceuticals and personal care products) and regulated organic pollutants pose a serious threat to water quality and their presence and spatial distribution are complicated to address as they can derive from several factors: distribution of point and diffuse sources, environmental conditions, hydrogeological features of the region and inherent properties of the considered contaminants. In this study, a ground and surface water monitoring campaign was conducted in the three main detritic groundwater bodies of an extensive and heavily modified river basin in order to draft an initial description of the occurrence and distribution of a wide range of organic contaminants. In total, 63 out of 185 target pollutants were detected. An attempt to understand the importance of different factors governing the distribution of some of the most frequently found pollutants was made. Antibiotics spatial distribution is potentially influenced by the hydrogeological functioning of the basin modified by hydraulic infrastructures (reflected by hydrochemistry and environmental tracers delta H-2 and delta O-18), not directly related to the distribution of potential sources. The presence of other organic pollutants does not reflect an evident correlation with flow pathways. Differences in contaminant occurrence are potentially attributed to the way pollutants are released into the environment as well as physico-chemical properties

Diseño y aplicación educativa de un programa de simulación para el aprendizaje de técnicas experimentales con sistemas de adquisición de datos

En este trabajo se describe una experiencia educativa sobre el uso de las tecnologías de la información y la comunicación en el aprendizaje de técnicas experimentales, que es un tema importante para el desarrollo de prácticas de laboratorio de Física, en las carreras universitarias de ciencias e ingeniería. La experiencia se ha centrado en diseñar y utilizar un programa de simulación que pretende mejorar el aprendizaje de procedimientos científicos, relacionados con la recogida y análisis de datos experimentales, utilizando un sistema informático de adquisición de datos que se conecta en cada experiencia a varios sensores físicos

Study of the presence and environmental risk of organic contaminants policed by the European Union and other organic compounds in the water resources of a region overlapping protected areas: The Guadiaro River basin (southern Spain)

The study presented here is a first qualitative assessment of the occurrence of organic contaminants contemplated and not yet contemplated in European Union environmental legislation in water resources in the little anthropized Guadiaro River basin (70% of its area is covered by natural vegetation), in southern Spain. Water samples were collected from four carbonate aquifers, two detrital aquifers and four surface water courses and were analyzed for (i) 171 organic contaminants, (ii) major ions and (iii) stable isotopes (δ18OH2O, δ2HH2O, δ13CDIC). An environmental risk assessment was conducted through calculation of risk quotients comparing measured concentrations with ecotoxicological data found in the literature. Twenty-five organic contaminants were detected, at least once, including pesticides, pharmaceuticals, drugs of abuse and polycyclic aromatic hydrocarbons (PAHs). Cocaine and its main metabolite were detected in 85% and 95% of water samples, respectively (0.001–0.18 μg/L and 0.004–0.6 μg/L, respectively). Pyrene (PAH) was found in all water samples (0.001–0.015 μg/L) and forest fires were pointed out as a potential diffuse source. Relationship between rivers and aquifers is reflected by the distribution of organic contaminants, essentially the drugs of abuse. Concentration of contaminants were generally higher in groundwater samples, especially from detrital aquifers, potentially due to an accumulation process promoted by irrigation-return flows and by its slow dynamic compared to that of karstic systems. Pyrene concentration was also higher in some springs from karstic aquifers. Hence, calculated risk quotients were in general higher in groundwater, meaning that the threat to surface aquatic systems can grow as aquifers increase their influence on the water courses as the dry season progresses. The relationship between δ13CDIC and most organic contaminants (especially pyrene) reveal the role of the soil as storage media.Funding for open access charge: Universidad de Málaga / CBU

The nervous system of Xenacoelomorpha: a genomic perspective

Xenacoelomorpha is, most probably, a monophyletic group that includes three clades: Acoela, Nemertodermatida and Xenoturbellida. The group still has contentious phylogenetic affinities; though most authors place it as the sister group of the remaining bilaterians, some would include it as a fourth phylum within the Deuterostomia. Over the past few years, our group, along with others, has undertaken a systematic study of the microscopic anatomy of these worms; our main aim is to understand the structure and development of the nervous system. This research plan has been aided by the use of molecular/developmental tools, the most important of which has been the sequencing of the complete genomes and transcriptomes of different members of the three clades. The data obtained has been used to analyse the evolutionary history of gene families and to study their expression patterns during development, in both space and time. A major focus of our research is the origin of 'cephalized' (centralized) nervous systems. How complex brains are assembled from simpler neuronal arrays has been a matter of intense debate for at least 100 years. We are now tackling this issue using Xenacoelomorpha models. These represent an ideal system for this work because the members of the three clades have nervous systems with different degrees of cephalization; from the relatively simple sub-epithelial net of Xenoturbella to the compact brain of acoels. How this process of 'progressive' cephalization is reflected in the genomes or transcriptomes of these three groups of animals is the subject of this paper