Assessment of membrane plants for biogas upgrading to biomethane at zero methane emission

In the future energy infrastructure there is a considerable potential for biogas and, in particular, for biomethane as a natural gas substitute. Among the alternatives of upgrading biogas to biomethane, this work focuses on membrane permeation. Taking cellulose acetate as membrane material and spiral-wound as membrane configuration, five layouts are assessed. All layouts have the same biogas plant rated at 500 m3/h (STP), yet they may adopt: (i) one- or two-stage permeation, (ii) permeate or residue recycle, and (iii) a water heater or a prime mover (internal combustion engine or a micro gas turbine) to exploit residues as fuel gas. Since residues are consumed, all layouts have zero emission of methane into the atmosphere. The membrane material is modeled considering the phenomenon of plasticization; the membrane modules are described by a crossflow permeation patterns without pressure drops. The results indicates that specific membrane areas range from 1.1 to 2.4 m2h/m3 (STP), specific energy from 0.33 to 0.47 kWh/m3 (STP), and exergy efficiencies from 57.6% to 88.9%. The splitting of permeation over two stages and the adoption of water heater instead of prime movers is a convenient option. The preferred layout employs a single compressor, a two-stage membrane permeation at 26 bar, a water heater fueled by the first-stage permeate, and a second-stage permeate recycle. Assuming a biomethane incentive of 80 €/MWhLHV and a project life of 15 years, the total investment of this plant is 2.9 M€, the payback time 5 years and the net present value 3.5 M€

Susceptibility of halobacteria to heavy metals

Sixty-eight halobacteria, including both culture coUection strains and fresh isolates from widely dift'ering geographical areas, were tested for susceptibility to arsenate, cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, and zinc ions by an agar dilution technique. The culture collection strains showed dift'erent susceptibilities, clustering into five groups. Halobacterium medilerranei and Halobacterium volcanii were the most metal tolerant, whereas Haloarcula californiae and Haloarcula sinaiiensis had the highest susceptibilities of the culture collection strains. Dift'erent patterns of metal susceptibility were found for all the halobacteria tested, and there was a uniform susceptibility to mercury and silver. All strains tested were multiply metal tolerant

Isolation and partial characterization of a plasmid in the extremely halophilic archaebacterium Halococcus morrhuae CCM 537

The extremely halophilic archaebacterium Halococcus morrhuae CCM 537 was found to contain’’ a plasmid, pHM2, of 6.0 kb. A restriction map was constructed. Southern hybridization of pHM2 DNA to DNA extracted from other Halococcus sp. strains revealed the presence of a similar plasmid in one other strain. A plasmid of Halobacterium trapanicum shared common sequences with pHM2. Other plasmids from halobacteria displayed no homology with pHM2. The characterization of pHM2 may make it useful for the development of cloning vectors for extremely halophilic archaebacteria

Relationships among multiple intelligences, motor performance and academic achievement in secondary school children

This study examines the relationships between multiple intelligences, academic achievement and motor performance in a group of secondary school children. Four hundred and eighty schoolchildren participated in this study (171 female and 309 male) with an average age of 13.33 years (SD: 1.41). The Revised self-efficacy Inventory for Multiple Intelligences (IAIM-R) and the motor test Sportcomp were applied, and the average results of the academic year they had made were obtained. The analysis of the results showed how female scored significantly higher on the Linguistic, Spatial and Interpersonal intelligences, and older pupils scored significantly higher on the linguistic and naturalistic intelligences. It was the logical-mathematical intelligence which showed significant relationships with academic performance and it was the intelligence that better predicted this achievement. It was the bodily-kinesthetic intelligence that was significantly related to motor competence and the best intelligence that predicted its achievement. Finally, indicate that schoolchildren with better scores in the motor test were those who scored higher in both academic achievement and all the multiple intelligences, with the exception of musical intelligence

La intenciòn de practicar en el futuro en escolares adolescentes

El presente estudio tuvo como objetivo analizar las intenciones de ser activos en el futuro de un grupo de escolares adolescentes así como qué variables podrían predecir mejor esta. Participaron 480 escolares de 11 a 16 años (M= 13.33 años; DT= 1.41) de los cuales 309 fueron varones y 171 mujeres de centros de la Comunidad de Madrid y Castilla La Mancha. Todos ellos cumplimentaron el Inventario de Conductas Saludables HBSC en la versión española de Castillo et al. (1997), referido a aspectos personales, sociales y ambientales de la práctica de actividades físicas y deportivas. Los resultados mostraron que la tasa de participación y de práctica en actividades deportivas está descendiendo en general y de forma particular en las chicas. La comparación con el estudio de 1997 así lo atestigua. Para los participantes las variables que mejor predicen su intención de practicar en el futuro fueron las autopercepciones de competencia deportiva, de forma física y de salud, a las cuales habría que añadir la práctica de las personas más significativas y la pertenencia activa a un club deportivo. De este estudio se desprende una consecuencia muy clara, la necesidad de incrementar la práctica en estas edades, de ofrecer experiencias confirmatorias que les permitan fortalecer su competencia real en el ámbito deportivo, sobre todo en el caso de las chicas

Étude ultrastructurale de la morphogenese corticale. De régénération chez le cilié hypotriche histriculus similis

La régénération chez Histriculus similis a été étudiée en microscopie électronique. Les premiers signes du procesus de régénération s'observenl une heure apres le traitement par l'urée. Pendant la morphogenese corticale de régénération tanl du primordium oral que des primordiums de la ciliature parorale et des cirres, les états premiers sont constitués par des couples de cinétosomes, qui portent des microtubules postciliaires dans le cinétosome postérieur et des microtubules transverses a l'antérieur. L'orientation de ces couples dépend du primordium qu'ils vonl produire. Une fois que les couples de cinétosomes sont alignés, a Iieu une prolifération de nouveaux cinélosomes proches de ces couples. Plus tard il y a une fragmentation transversale de ces primordiums , a l'exception du primordium paroral qui se divise longitudinalement.The cortical morphogenesis of regeneration in Histriculus similis has been studied in this work at level of electronic microscopy. The first signs of the regeneration process become evident one hour after the treatment with urea. During the early steps of the cortical morphogenesis of regeneration, the oral primordium , paroral ciliation primordium and the ciliary streaks, are formed by pairs of kinetosomes. These pairs carry postciliary microtubules in the posterior kinetosome and transverse microtubules in the anterior one. The orientation of these pairs of kinetosomes depends on the type of primordium that is going to be formed. Once the pairs of kinetosomes are aligned, there is a proliferation of new kinetosomes in the vicinity of these pairs of kinetosomes. Afterwards there is a transversal fragmentation of the above mentioned primordia, with the exception of the paroral primordium that is longitudinally divided

Characterization of a plasmid from moderately halophilic eubacteria

A plasmid has been isolated for the first time from moderately halophilic eubacteria. Halomonas elongata, Halomonrrs halmphila, Deleya halophila and Vibrio costkola were found to harbour an 11.5 kbp plasmid (pMH1). The plasmid was isolated and characterized after transformation into Escherichia coh'JM101 cells. A restriction map was constructed, and unique restriction sites for EcoRI, EcoRV and ClaI were detected. The occurrence of such a plasmid in the original halophilic strains was confirmed by Southern hybridization. The plasmid carries genetic determinants that mediate resistance to kanamycin, tetracycline, and neomycin. This property, together with its relatively small size, its stability in E colicells, and the presence of unique restriction sites, makes pMHl a good candidate for the development of a cloning vector for moderate halophiles

Impact of Probiotics on the Prevention and Treatment of Gastrointestinal Diseases in the Pediatric Population

Despite the high prevalence of gastrointestinal disorders (GIDs) in infants and children, especially those categorized as functional GIDs (FGIDs), insufficient knowledge about their pathophysiology has limited both symptomatic diagnosis and the development of optimal therapies. Recent advances in the field of probiotics have made their potential use as an interesting therapeutic and preventive strategy against these disorders possible, but further efforts are still needed. In fact, there is great controversy surrounding this topic, generated by the high variety of potential probiotics strains with plausible therapeutic utility, the lack of consensus in their use as well as the few comparative studies available on probiotics that record their efficacy. Taking into account these limitations, and in the absence of clear guidelines about the dose and timeframe for successful probiotic therapy, our review aimed to evaluate current studies on potential use of probiotics for the prevention and treatment of the most common FGIDs and GIDs in the pediatric population. Furthermore, matters referring to know major action pathways and key safety recommendations for probiotic administration proposed by major pediatric health agencies shall also be discussed

Expectations about foreign students in a peripheral neighborhood of Granada (Spain): educational trajectories under the filter of culturalism

Ha pasado más de una década desde el boom migratorio en España, donde la llegada de alumnado de origen extranjero ha dejado de ser una novedad en las aulas. Este artículo se interesa sobre la percepción que la trayectoria educativa del alumnado extranjero en la educación obligatoria tienen tanto el personal docente como los progenitores. El estudio se centra en si dicha percepción es positiva u optimista, y en examinar qué tipo de variables se sopesan en los discursos. Especialmente el recurso a una supuesta especificidad cultural, como eje principal en las percepciones, o la introducción de otras variables sociales. Se trata de un estudio cualitativo de carácter local realizado en un barrio de la ciudad de Granada con una notable presencia de inmigrantes, aunque sin llegar a cuotas altas de segregación.It has been more than a decade since the immigration boom in Spain. The arrival of students of foreign origin has ceased to be a novelty in the Spanish school classrooms. In this article, we are interested in the perception of the educational trajectory of foreign students in compulsory education for both teachers and parents. There are two points that are analyzed: first, if this perception is positive or optimistic, and secondly, to examine what type of variables are weighed in the discourses. Especially the recourse to a supposed cultural specificity as the main axis in the perceptions or the introduction of other social variables. It´s a qualitative study of a local character conducted in a neighborhood of Granada with a notable presence of immigrants, although without reaching high rates of segregation

Autopercepción de inteligencia contextual para jugar y de competencia decisional en el fútbol = Game intelligence and perceived competence to decide on soccer players

En el presente estudio se analizó la autopercepción de competencia decisional y la inteligencia contextual de jugadores de fútbol de diferente nivel de pericia. Además, se exploraron las relaciones existentes entre las autopercepciones de competencia para decidir y de inteligencia contextual en jugadores de fútbol, para lo cual participaron voluntariamente 467 jugadores (M = 20,26, DT = 4,83). El nivel de pericia de los participantes se estableció en tres diferentes: Autonómico (N = 141), nacional (N = 253) e internacional (N = 73), de un total de 46 clubes españoles así como de varias selecciones nacionales. Se utilizaron dos instrumentos en forma de cuestionarios. El primero fue el Cuestionario de Inteligencia Contextual Percibida en el Deporte (ICD) y el segundo el de Estilos de Toma de Decisión en el Deporte (CETD). Los resultados mostraron que la competencia decisional y la inteligencia contextual están relacionadas y mejoran según aumenta el nivel deportivo. ----------ABSTRACT---------- The aim of this paper was to analyze decisional competence and contextual intelligence in sport among different level of expertise football players. In addition, the relationship between self-perceptions of decisional competence and contextual intelligence was assessed. Participants were 467 football players (M=20,26, DT=5,43). They were assigned three levels of expertise: Autonomic (N = 141), National (N = 253) and International (N = 73), from a group of 46 spanish clubs and several national teams. The Contextual Intelligence in Sport Questionnaire (ICD) and the Decision Making in Sport Questionnaire (CETD) were used to explore self-perceptions of players. Results showed that self-perceptions of Contextual Intelligence and Decision Making increased with the level of expertise