2,013 research outputs found
Optical observations of very low ionization HII regions in the large Magellanic cloud
Several very low ionization isolated HII regions were detected on a prism-objective plate of the Large Magellanic Cloud. Most of the objects show a very weak (OIII) lambda 5007 emission line and, on the other hand the (OII) lambda 6584 doublets are very intense. This kind of objects seem to be ideal in order to determine accurate N and O abundance, avoiding the use of large ionization correction factors in the N abundance determination. Spectrophotometric observations of these regions were carried out with the 4 m telescope and the 2-D Frutti spectrograph at Cerro Tololo, and with the 1.52 m and the Image Dissector Scanner (IDS) at La Silla, ESO. The wavelength range lambda lambda 3700 to 7000 A was covered. Calibrated fluxes of the emission lines detected were measured, and from these data preliminary results of physical conditions of the gas as well as some ionic abundances were derived. Comparisons of the observations with ionization structure models show that the effective temperatures of the ionizing stars are less than 35,000 K. Possible abundances gradients across the large megallanic cloud are discussed
Garlic derivatives (PTS and PTS-O) differently affect the ecology of swine faecal microbiota in vitro
A number of in vitro experiments were designed to evaluate the effects of two different industrial products, namely PROALLIUM-S-DMC and PROALLIUM-SO-DMC (DMC Research Center, Granada, Spain), obtained from garlic (Allium sativum) on the faecal microbiota of pigs. The effects of three different concentrations (50, 200 and 400 ppm) of the active compounds (PTS and PTS-O, respectively) from both industrial products on the gastrointestinal microbiota of pigs were tested. Growth medium without any additive (0 ppm) was used as control. Predominant bacterial groups (total aerobes, total anaerobes,lactobacilli, bifidobacteria, coliforms, enterobacteria, bacteroides and clostridia) were studied. Results showed that both PTS and PTS-O have significant (P < 0.01) antimicrobial activity against every group studied, although enterobacteria and coliforms were the most affected populations (P < 0.01). Time kill curves for Escherichia coli and Salmonella typhimurium, two common pathogens of pigs, showed that both compounds had a
bactericidal effect against these strains. For the bacterial groups here studied, the
antimicrobial effect of PTS-O was significantly (P < 0.001) stronger than that of PTS. Trials in vivo are in course to study the potential use of these products as alternatives to antibiotics in pig feeds.Peer reviewe
Artificial intelligence and journalism: Systematic review of scientific production in Web of Science and Scopus (2008-2019)
Research about the use of Artificial Intelligence applied to journalism has increased over the years. The studies conducted in this field between January 2008 and December 2019 were analysed to understand the contexts in which they have been developed and the challenges detected. The method used consisted of a systematic review of the scientific literature (SLR) of 209 scientific documents published in the Web of Science and Scopus databases. The validation required the inclusion and exclusion criteria, database identification, search engines and evaluation and description of results. The findings indicate that the largest number of publications related to this topic are concentrated in the United States and that the rise of scientific production on Artificial Intelligence in journalism takes place in 2015, when the remarkable growth of these publications begins, until reaching 61 in 2019. It is concluded that research is mainly published in scientific journals, which include works that handle a broad variety of topics, such as information production, data journalism, big data, application in social networks or information checking. In relation to authorship, the trend is the presence of a single signer.La investigación sobre el uso de la Inteligencia Artificial aplicada al periodismo se ha intensificado en los últimos años. Este artículo analiza los estudios producidos en este campo entre enero 2008 y diciembre 2019, a fin de conocer qué investigaciones se han realizado y cuáles son los contextos en los que se han desarrollado. El método ha sido una revisión sistemática de la literatura científica (SLR) de 209 documentos científicos publicados en las bases de datos Web of Science y Scopus. La validación ha seguido los criterios de inclusión y exclusión, identificación de la base de datos, motores de búsqueda y evaluación y descripción de resultados. Los hallazgos indican que en Estados Unidos se concentra el mayor número de publicaciones relacionadas con este tema y que el auge de la producción científica sobre la Inteligencia Artificial en periodismo se produce en 2015, cuando empieza el crecimiento notable de estas publicaciones, hasta alcanzar las 61 en 2019. Se concluye que las investigaciones se publican principalmente en revistas científicas, que incluyen trabajos que versan sobre una amplia variedad de temas, como la producción informativa, el periodismo de datos, el big data, la aplicación en redes sociales o el chequeo de información. En relación con la autoría, la tendencia es la presencia de un único firmante
Cognitive Fusion Mediates the Relationship between Dispositional Mindfulness and Negative Affects: A Study in a Sample of Spanish Children and Adolescent School Students
Nowadays, mindfulness-based interventions (MBI) have experienced a remarkable
development of studies among childhood and adolescent interventions. For this reason, dispositional
mindfulness (DM) measures for children and adolescents have been developed to determine the
e ectiveness of MBI at this age stage. However, little is known about how key elements of
DM (for example, cognitive de/fusion or experiential avoidance that both confirm psychological
inflexibility) are involved in the mechanisms of the children and adolescents’ mental health outcomes.
This research examined the mediating e ect of cognitive fusion between DM and anxiety and other
negative emotional states in a sample of 318 Spanish primary-school students (aged between 8 and 16
years, M = 11.24, SD = 2.19, 50.8% males). Participants completed the AFQ-Y (Avoidance and Fusion
Questionnaire for youth), which is a measure of psychological inflexibility that encompasses cognitive
defusion and experiential avoidance; CAMM (DM for children and adolescents), PANAS-N (positive
and negative a ect measure for children, Spanish version of PANASC), and STAIC (an anxiety
measure for children). The study accomplished ethical standards. As MBI relevant literature has
suggested, cognitive defusion was a significant mediator betweenDMand symptoms of both negative
emotions and anxiety in children and adolescents. However, experiential avoidance did not show
any significant mediating relationship. Probably, an improvement of the assessment of experiential
avoidance is needed. MBI programs for children and adolescents may include more activities for
reducing e ects of the cognitive defusion on their emotional distress
Fluxtube model atmospheres and Stokes V zero-crossing wavelengths
First results of the inversion of Stokes I and V profiles from plage regions
near disk center are presented. Both low and high spatial resolution spectra of
FeI 6301.5 and FeI 6302.5 A obtained with the Advanced Stokes Polarimeter (ASP)
have been considered for analysis. The thin flux tube approximation,
implemented in an LTE inversion code based on response functions, is used to
describe unresolved magnetic elements. The code allows the simultaneous and
consistent inference of all atmospheric quantities determining the radiative
transfer with the sole assumption of hydrostatic equilibrium. By considering
velocity gradients within the tubes we are able to match the full ASP Stokes
profiles. The magnetic atmospheres derived from the inversion are characterized
by the absence of significant motions in high layers and strong velocity
gradients in deeper layers. These are essential to reproduce the asymmetries of
the observed profiles. Our scenario predicts a shift of the Stokes V
zero-crossing wavelengths which is indeed present in observations made with the
Fourier Transform Spectrometer.Comment: To appear in ApJ Letters (1997) (in press
Aplicación de técnicas SIG en el estudio de evaluación de degradación de suelos. Mazarrón (Murcia)
El objetivo general de este estudio ha sido evaluar el estado actual y los cambios que se han producido en
algunas características edáficas del área de Mazarrón (Murcia) en un periodo de 20 años, en relación con los
procesos de degradación. Para ello se han utilizado los resultados de dos muestreos de suelos realizados en
un intervalo de veinte años (1988 y 2008). Se han analizado algunas de las características edáficas que más
relación tienen con la vulnerabilidad de los suelos a la erosión (Textura, Materia orgánica y Pedregosidad) y de
las cuales se disponía de datos en los dos muestreos.
Para la creación y análisis de la información espacial se han empleado dos Sistemas de Información
Geográfica de software libre. Uno de ellos ha sido GvSIG, desarrollado por la Generalitat Valenciana y el
programa GRASS. La metodología SIG empleada ha sido una herramienta fundamental para obtener la serie
de capas de variables edáficas para los años 1988 y 2008.
Los resultados muestran como el área de estudio es bastante vulnerable a los procesos erosivos, sobre
todo por erosión hidrica y antrópica, debido a las características de sus suelos. Riesgo que se incrementaría si
en futuro se abandonaran los cultivos.The main objetive of these study is to evaluate the current situation and the changes ocurred in some
edaphic characteristics of the soils in the Mazarrón area (Murcia) in a twenty years period, in relation with the
degradation processes. For these propose we have used the results of two soils samples carried out in a
twenty years intervale (1988 and 2008). The caracteristics more related with the vulnerability of the soil
erosion (texture, organic matter and stoniness) of wich we had data of the two samples were evaluated.
Two Geografical Information System of free software have been used for the creation and analisis of the
espacial information. One of these was GvSIG, developed by Generalitat Valenciana and GRASS programme.
The GIS methodology carried out was a fundamental tool to obtain edaphic variables layers for the years 1988
and 2008.
The results show how the study area is very sensible to the erosive processes, specialy by hidric and
antropic erosion, because soil caracteristics. This hazard would increase in a future if the land was
abandoned
Community-acquired pneumonia: development of a bedside predictive model and scoring system to identify the aetiology
AbstractAlthough initial presentation has been commonly used to select empirical therapy in patients with community-acquired pneumonia (CAP), few studies have provided a quantitative estimation of its value. The objective of this study was to analyse whether a combination of basic clinical and laboratory information performed at bedside can accurately predict the aetiology of pneumonia.A prospective study was developed among patients admitted to the Emergency Department University Hospital Arnau de Vilanova, Lleida, Spain, with CAP. Informed consent was obtained from patients in the study. At entry, basic clinical (age, comorbidity, symptoms and physical findings) and laboratory (white blood cell count) information commonly used by clinicians in the management of respiratory infections, was recorded. According to microbiological results, patients were assigned to the following categories: bacterial (Streptococcus pneumoniae and other pyogenic bacteria), virus-like (Mycoplasma pneumoniae, Chlamydia spp and virus) and unknown pneumonia. A scoring system to identify the aetiology was derived from the odds ratio (OR) assigned to independent variables, adjusted by a logistic regression model. The accuracy of the prediction rule was tested by using receiver operating characteristic curves.One hundred and three consecutive patients were classified as having virus-like (48), bacterial (37) and unknown (18) pneumonia, respectively. Independent predictors related to bacterial pneumonia were an acute onset of symptoms (OR 31; 95% Cl, 6–150), age greater than 65 or comorbidity (OR 6·9; 95% Cl, 2–23), and leukocytosis or leukopenia (OR 2; 95% Cl, 0·6–7). The sensitivity and specificity of the scoring system to identify patients with bacterial pneumonia were 89% and 94%, respectively. The prediction rule developed from these three variables classified the aetiology of pneumonia with a ROC curve area of 0·84.Proper use of basic clinical and laboratory information is useful to identify the aetiology of CAP. The prediction rule may help clinicians to choose initial antibiotic therapy
Photospheric structure of an extended penumbra
The photospheric structure of an extended penumbra belonging to a complex spot observed near disk center is investigated by means of the inversion of the full Stokes vector of two Fe I lines at 1.56 μm. An attempt is made to classify the observed Stokes V profiles in terms of their shapes. It turns out that about 28% of the profiles have abnormal shapes indicative of two different magnetic-field
components within the resolution element. The spatial distribution of abnormal Stokes V profiles is studied. It is found that such profiles are evenly distributed in the penumbra, without any particular tendency to concentrate near the so-called neutral line. Anomalous profiles are not only seen in the outer penumbra and beyond, but also in the middle part of it. A Milne-Eddington–like inversion is
carried out first, revealing a smooth picture of the spatial distribution of magneticfield vector and velocities along the line of sight. In particular, dark spines with
stronger and more vertical magnetic fields are seen to coexist with nearly horizontal magnetic fields throughout the penumbra. A full inversion allowing for gradients of
the atmospheric parameters along the line of sight indicates the existence of cool magnetic tubes returning back to the solar surface (inclination angles greater than
90◦) and carrying the largest material flows
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