8,420 research outputs found

    Bacterial Active Community Cycling in Response to Solar Radiation and Their Influence on Nutrient Changes in a High-Altitude Wetland

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    IndexaciĂłn: Web of Science; Scopus.Microbial communities inhabiting high-altitude spring ecosystems are subjected to extreme changes in solar irradiance and temperature throughout the diel cycle. Here, using 16S rRNA gene tag pyrosequencing (cDNA) we determined the composition of actively transcribing bacteria from spring waters experimentally exposed through the day (morning, noon, and afternoon) to variable levels of solar radiation and light quality, and evaluated their influence on nutrient recycling. Solar irradiance, temperature, and changes in nutrient dynamics were associated with changes in the active bacterial community structure, predominantly by Cyanobacteria, Verrucomicrobia, Proteobacteria, and 35 other Phyla, including the recently described Candidate Phyla Radiation (e.g., Parcubacteria, Gracilibacteria, OP3, TM6, SR1). Diversity increased at noon, when the highest irradiances were measured (3.3-3.9 H', 1125 W m(-2)) compared to morning and afternoon (0.6-2.8 H'). This shift was associated with a decrease in the contribution to pyrolibraries by Cyanobacteria and an increase of Proteobacteria and other initially low frequently and rare bacteria phyla (< 0.5%) in the pyrolibraries. A potential increase in the activity of Cyanobacteria and other phototrophic groups, e.g., Rhodobacterales, was observed and associated with UVR, suggesting the presence of photo activated repair mechanisms to resist high levels of solar radiation. In addition, the percentage contribution of cyanobacterial sequences in the afternoon was similar to those recorded in the morning. The shifts in the contribution by Cyanobacteria also influenced the rate of change in nitrate, nitrite, and phosphate, highlighted by a high level of nitrate accumulation during hours of high radiation and temperature associated with nitrifying bacteria activity. We did not detect ammonia or nitrite oxidizing bacteria in situ, but both functional groups (Nitrosomona and Nitrospira) appeared mainly in pyrolibraries generated from dark incubations. In total, our results reveal that both the structure and the diversity of the active bacteria community was extremely dynamic through the day, and showed marked shifts in composition that influenced nutrient recycling, highlighting how abiotic variation affects potential ecosystem functioning.http://journal.frontiersin.org/article/10.3389/fmicb.2016.01823/ful

    Cartoons vs. manga movies : a brief history of anime in the UK

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    This paper has as main objective to explore, adopting a historical and critical perspective, the release of film and anime TV in UK. This would be a first step towards the studio of the peculiar implementation of manganime Culture in Britain. Compared with other European countries, UK has shown to be slower and even reluctant in importing Japanese television products. Thus, while major markets of anime such as France, Italy or Spain expanded considerably during 1975-1995 period, in a recurrent synergy of television markets, and technological publishing, the implantation of the principal channel (televised anime) in UK has been irregular and unstable. Even today, the catalogue of broadcasting anime is limited to some high success movies, late night television on thematic channels and quite recently, video-on-demand services (Netflix). The offer cannot be compare in importance and diversity to other European countries. This fact, far from being anecdotal, has had an impact on the subsequent implantation of media Japanese cultures such as manga, anime, video games and cosplay. What can be the reason of this irregular development of Japanese visual culture in United Kingdom? Characteristic having the television market and / or the UK audience? Main hypothesis in relation to these issues can be considered to be of sociological character, but are reflected in the idiosyncrasies of British television culture and production system. Thus, compared to other Western markets (including the US) which saw the opportunity to purchase economic products for children’s television audiences in the late 70s and early 80s, the British ‘telly’ already offered a broad catalogue (Roobarb, Super Ted, Danger Mouse, etc. ...). The only exception to this children’s ‘made in Britain’ programming was the co-production model. This caused a leak of few products that were not even considered as “Japanese” (Seven Cities of Gold, Godzilla) but mere ‘cartoons’. This competition with the British children production as well as the wide catalogue of other forms of British Popular Culture would explain why the film, domestic video and later adults programming would be the marginal routes of entry for manganime

    Symphony on strong field approximation

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    This paper has been prepared by the Symphony collaboration (University of Warsaw, Uniwersytet Jagiellonski, DESY/CNR and ICFO) on the occasion of the 25th anniversary of the 'simple man's models' which underlie most of the phenomena that occur when intense ultrashort laser pulses interact with matter. The phenomena in question include high-harmonic generation (HHG), above-threshold ionization (ATI), and non-sequential multielectron ionization (NSMI). 'Simple man's models' provide both an intuitive basis for understanding the numerical solutions of the time-dependent Schrodinger equation and the motivation for the powerful analytic approximations generally known as the strong field approximation (SFA). In this paper we first review the SFA in the form developed by us in the last 25 years. In this approach the SFA is a method to solve the TDSE, in which the non-perturbative interactions are described by including continuum-continuum interactions in a systematic perturbation-like theory. In this review we focus on recent applications of the SFA to HHG, ATI and NSMI from multi-electron atoms and from multi-atom molecules. The main novel part of the presented theory concerns generalizations of the SFA to: (i) time-dependent treatment of two-electron atoms, allowing for studies of an interplay between electron impact ionization and resonant excitation with subsequent ionization; (ii) time-dependent treatment in the single active electron approximation of 'large' molecules and targets which are themselves undergoing dynamics during the HHG or ATI processes. In particular, we formulate the general expressions for the case of arbitrary molecules, combining input from quantum chemistry and quantum dynamics. We formulate also theory of time-dependent separable molecular potentials to model analytically the dynamics of realistic electronic wave packets for molecules in strong laser fields. We dedicate this work to the memory of Bertrand Carre, who passed away in March 2018 at the age of 60
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