168 research outputs found

    Assessing the surface modifications following the mechanochemical preparation of a Ag/Al2O3 selective catalytic reduction catalyst

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    The surface modification of a mechanochemically prepared Ag/Al2O3 catalyst compared with catalysts prepared by standard wet impregnated methods has been probed using two-dimensional T1–T2 NMR correlations, H2O temperature programmed desorption (TPD) and DRIFTS. The catalysts were examined for the selective catalytic reduction of NOx using n-octane in the presence and absence of H2. Higher activities were observed for the ball milled catalysts irrespective of whether H2 was added. This higher activity is thought to be related to the increased affinity of the catalyst surface towards the hydrocarbon relative to water, following mechanochemical preparation, resulting in higher concentrations of the hydrocarbon and lower concentrations of water at the surface. DRIFTS experiments demonstrated that surface isocyanate was formed significantly quicker and had a higher surface concentration in the case of the ball milled catalyst which has been correlated with the stronger interaction of the n-octane with the surface. This increased interaction may also be the cause of the reduced activation barrier measured for this catalyst compared with the wet impregnated system. The decreased interaction of water with the surface on ball milling is thought to reduce the effect of site blocking whilst still providing a sufficiently high surface concentration of water to enable effective hydrolysis of the isocyanate to form ammonia and, thereafter, N2

    Resource distributions affect social learning on multiple timescales

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    We study how learning is shaped by foraging opportunities and self-organizing processes and how this impacts on the effects of “copying what neighbors eat” on multiple timescales. We use an individual-based model with a rich environment, where group foragers learn what to eat. We vary foraging opportunities by changing local variation in resources, studying copying in environments with pure patches, varied patches, and uniform distributed resources. We find that copying can help individuals explore the environment by sharing information, but this depends on how foraging opportunities shape the learning process. Copying has the greatest impact in varied patches, where local resource variation makes learning difficult, but local resource abundance makes copying easy. In contrast, copying is redundant or excessive in pure patches where learning is easy, and mostly ineffective in uniform environments where learning is difficult. Our results reveal that the mediation of copying behavior by individual experience is crucial for the impact of copying. Moreover, we find that the dynamics of social learning at short timescales shapes cultural phenomena. In fact, the integration of learning on short and long timescales generates cumulative cultural improvement in diet. Our results therefore provide insight into how and when such processes can arise. These insights need to be taken into account when considering behavioral patterns in nature

    One foot in the rave: Ageing ravers’ transitions to adulthood and their participation in rave culture

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    Challenging adolescence limited life-course theory, this article presents the results of an online survey (2016) that aimed to establish if, how and to what extent ageing ravers continue to participate in rave culture. The survey collected data from members of the original rave generation. We explored the ravers’ transitions to adulthood, and how these influenced their participation in club culture. We found that our ravers continued to participate in rave culture; their persistence is related to the frequency of their engagement at a younger age. Adopting interdisciplinarity, we apply theories from both life course research and youth culture studies and argue that the persistence of leisure practices, such as raving, can be understood in the same way as persistence of drug use: frequent behavior in adolescence determines persistence in older adulthood. Consequently, we are able to recognize patterns of leisure beyond adolescence, thus making leisure choices more predictable

    Mechanoresponsive musculoskeletal tissue differentiation of adipose-derived stem cells

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    Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota)

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    Compared to the higher fungi (Dikarya), taxonomic and evolutionary studies on the basal clades of fungi are fewer in number. Thus, the generic boundaries and higher ranks in the basal clades of fungi are poorly known. Recent DNA based taxonomic studies have provided reliable and accurate information. It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines. Recently, Tedersoo et al. (MycoKeys 13:1--20, 2016) accepted Aphelidiomycota and Rozellomycota in Fungal clade. Thus, we regard both these phyla as members in Kingdom Fungi. We accept 16 phyla in basal clades viz. Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota. Thus, 611 genera in 153 families, 43 orders and 18 classes are provided with details of classification, synonyms, life modes, distribution, recent literature and genomic data. Moreover, Catenariaceae Couch is proposed to be conserved, Cladochytriales Mozl.-Standr. is emended and the family Nephridiophagaceae is introduced
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