On the deduction of galaxy abundances with evolutionary neural networks

A growing number of indicators are now being used with some confidence to measure the metallicity(Z) of photoionisation regions in planetary nebulae, galactic HII regions(GHIIRs), extra-galactic HII regions(EGHIIRs) and HII galaxies(HIIGs). However, a universal indicator valid also at high metallicities has yet to be found. Here, we report on a new artificial intelligence-based approach to determine metallicity indicators that shows promise for the provision of improved empirical fits. The method hinges on the application of an evolutionary neural network to observational emission line data. The network's DNA, encoded in its architecture, weights and neuron transfer functions, is evolved using a genetic algorithm. Furthermore, selection, operating on a set of 10 distinct neuron transfer functions, means that the empirical relation encoded in the network solution architecture is in functional rather than numerical form. Thus the network solutions provide an equation for the metallicity in terms of line ratios without a priori assumptions. Tapping into the mathematical power offered by this approach, we applied the network to detailed observations of both nebula and auroral emission lines in the optical for a sample of 96 HII-type regions and we were able to obtain an empirical relation between Z and S23 with a dispersion of only 0.16 dex. We show how the method can be used to identify new diagnostics as well as the nonlinear relationship supposed to exist between the metallicity Z, ionisation parameter U and effective (or equivalent) temperature T*.Comment: Accepted for publication in PASP. 6 pages, 2 figure

Using mobile media creation to structure museum interpretation with professional vision

Mobile technology plays an increasing role in museum and cultural heritage contexts. In most cases, these tools support the relatively passive consumption of expert interpretations, or the unguided generation of content by users. This paper explores the potential for technologies to help museum visitors, encountering unfamiliar objects, to engage with them as a skilled professional interpreter would, through structured mobile experiences that focus on creating multimedia content. We explore this concept in the area of artefact interpretation and specifically how to enact a structured process of interpretation, as would commonly be taught in courses dedicated to the analytical diagnostics of visual evidence, such as Classical Archaeology or Art History. We discuss two field trials of prototype systems through which the structured creation of multimedia forms a basis for learning to interpret historical artefacts conducted in contexts of both formal and informal learning. By describing, implementing, and evaluating this approach, we contribute understanding of a new way to conceptualise active engagement in museum contexts, through the effective use of scaffolding and user generation of multimedia. We identify issues around the properties and flexibilities of multiple media for this purpose, links between provision for procedural and factual learning, and the value of media creation-based structures in improving the skills and confidence to interpret

Eliokarmos humanii (Hyacinthaceae, Ornithogaloideae), a new species from Namaqualand in South Africa and a new combination in the genus

A new species of the southern Africa endemic genus Eliokarmos, that includes the well-known chincherinchees, is described from the vicinity of Kotzesrus, Northern Cape Province of South Africa. Eliokarmos humanii sp. nov. is unique in the genus based on its single, slightly fleshy, suborbicular, convex leaf with ciliate margin, and the short subspiciform inflorescence with almost sessile flowers. A complete description is presented for this species, and data on morphology, ecology, and distribution are reported. In addition, Ornithogalum richtersveldensis, recently described from northwestern South Africa, is transferred to Eliokarmos based on its morphology and biogeography, and a new combination is presented for this species in the latter genus.This work was partly supported by H2020 Research and Innovation Staff Exchange Programme of the European Commission, project 645636: ‘Insect-plant relationships: insights into biodiversity and new applications’ (FlyHigh), and the grants ACIE18–03 UAUSTI18–02 and UAUSTI19-08 from the University of Alicante

Effect of the C-alpha substitution on the ketonic decarboxylation of carboxylic acids over m-ZrO2: the role of entropy

[EN] The kinetics of the ketonic decarboxylation of linear and branched carboxylic acids over m-ZrO2 as a catalyst has been investigated. The same apparent activation energy is experimentally determined for the ketonic decarboxylation of both linear pentanoic and branched 2-methyl butanoic acids, while the change in entropy for the rate-determining step differs by nearly 50 kJ mol(-1). These results show that the difference in reactivity between linear and branched acids is due to entropic effects, and is related to the probability of finding the reactant molecules adsorbed and activated in a suitable way on the catalyst surface.The authors thank MINECO (Consolider Ingenio 2010-MULTICAT, CSD2009-00050 and Severo Ochoa program, SEV-2012-0267), Generalitat Valenciana (PROMETEOII/2013/011 Project), and the Spanish National Research Council (CSIC, Es 2010RU0108) for financial support. Red Espanola de Supercomputacion (RES) and Centre de Calcul de la Universitat de Valencia are gratefully acknowledged for computational facilities and technical assistance. A. P., F. G. and B. O.-T. thank MINECO (Juan de la Cierva and FPU Programme) and CSIC (JAE Programme) for their fellowships, respectively. M. R. is grateful to the Generalitat Valenciana for a BEST 2015 fellowship.Oliver-Tomás, B.; Gonell-Gómez, F.; Pulido, A.; Renz, M.; Boronat Zaragoza, M. (2016). Effect of the C-alpha substitution on the ketonic decarboxylation of carboxylic acids over m-ZrO2: the role of entropy. Catalysis Science and Technology. 6(14):5561-5566. https://doi.org/10.1039/c6cy00395hS55615566614Friedel, C. (1858). Ueber s. g. gemischte Acetone. Annalen der Chemie und Pharmacie, 108(1), 122-125. doi:10.1002/jlac.18581080124W. L. Howard , in Encyclopedia of Chemical Technology (Kirk-Othmer), Wiley-Interscience, New York, 4th edn, 1998, vol. 1, pp. 176–194H. Siegel and M.Eggersdorfer, Ullmann's Encyclopedia of Industrial Chemistry, VCH, Weinheim, 1990Huber, G. W., Iborra, S., & Corma, A. (2006). Synthesis of Transportation Fuels from Biomass:  Chemistry, Catalysts, and Engineering. Chemical Reviews, 106(9), 4044-4098. doi:10.1021/cr068360dCorma, A., Iborra, S., & Velty, A. (2007). Chemical Routes for the Transformation of Biomass into Chemicals. Chemical Reviews, 107(6), 2411-2502. doi:10.1021/cr050989dChheda, J. N., Huber, G. W., & Dumesic, J. A. (2007). Liquid-Phase Catalytic Processing of Biomass-Derived Oxygenated Hydrocarbons to Fuels and Chemicals. Angewandte Chemie International Edition, 46(38), 7164-7183. doi:10.1002/anie.200604274Renz, M. (2005). Ketonization of Carboxylic Acids by Decarboxylation: Mechanism and Scope. European Journal of Organic Chemistry, 2005(6), 979-988. doi:10.1002/ejoc.200400546Corma, A., Renz, M., & Schaverien, C. (2008). Coupling Fatty Acids by Ketonic Decarboxylation Using Solid Catalysts for the Direct Production of Diesel, Lubricants, and Chemicals. ChemSusChem, 1(8-9), 739-741. doi:10.1002/cssc.200800103Pham, T. N., Sooknoi, T., Crossley, S. P., & Resasco, D. E. (2013). Ketonization of Carboxylic Acids: Mechanisms, Catalysts, and Implications for Biomass Conversion. ACS Catalysis, 3(11), 2456-2473. doi:10.1021/cs400501hSerrano-Ruiz, J. C., Wang, D., & Dumesic, J. A. (2010). Catalytic upgrading of levulinic acid to 5-nonanone. Green Chemistry, 12(4), 574. doi:10.1039/b923907cAlonso, D. M., Bond, J. Q., & Dumesic, J. A. (2010). Catalytic conversion of biomass to biofuels. Green Chemistry, 12(9), 1493. doi:10.1039/c004654jCorma, A., Oliver-Tomas, B., Renz, M., & Simakova, I. L. (2014). Conversion of levulinic acid derived valeric acid into a liquid transportation fuel of the kerosene type. Journal of Molecular Catalysis A: Chemical, 388-389, 116-122. doi:10.1016/j.molcata.2013.11.015Rajadurai, S. (1994). Pathways for Carboxylic Acid Decomposition on Transition Metal Oxides. Catalysis Reviews, 36(3), 385-403. doi:10.1080/01614949408009466Gliński, M., Kijeński, J., & Jakubowski, A. (1995). Ketones from monocarboxylic acids: Catalytic ketonization over oxide systems. Applied Catalysis A: General, 128(2), 209-217. doi:10.1016/0926-860x(95)00082-8Pestman, R., Koster, R. M., van Duijne, A., Pieterse, J. A. Z., & Ponec, V. (1997). Reactions of Carboxylic Acids on Oxides. Journal of Catalysis, 168(2), 265-272. doi:10.1006/jcat.1997.1624Parida, K., & Mishra, H. K. (1999). Catalytic ketonisation of acetic acid over modified zirconia. Journal of Molecular Catalysis A: Chemical, 139(1), 73-80. doi:10.1016/s1381-1169(98)00184-8Hendren, T. S., & Dooley, K. M. (2003). Kinetics of catalyzed acid/acid and acid/aldehyde condensation reactions to non-symmetric ketones. Catalysis Today, 85(2-4), 333-351. doi:10.1016/s0920-5861(03)00399-7Martinez, R. (2004). Ketonization of acetic acid on titania-functionalized silica monoliths. Journal of Catalysis, 222(2), 404-409. doi:10.1016/j.jcat.2003.12.002Pulido, A., Oliver-Tomas, B., Renz, M., Boronat, M., & Corma, A. (2012). Ketonic Decarboxylation Reaction Mechanism: A Combined Experimental and DFT Study. ChemSusChem, 6(1), 141-151. doi:10.1002/cssc.201200419Ignatchenko, A. V., DeRaddo, J. S., Marino, V. J., & Mercado, A. (2015). Cross-selectivity in the catalytic ketonization of carboxylic acids. Applied Catalysis A: General, 498, 10-24. doi:10.1016/j.apcata.2015.03.017Ignatchenko, A. V., & Kozliak, E. I. (2012). Distinguishing Enolic and Carbonyl Components in the Mechanism of Carboxylic Acid Ketonization on Monoclinic Zirconia. ACS Catalysis, 2(8), 1555-1562. doi:10.1021/cs3002989Ignatchenko, A. V. (2011). Density Functional Theory Study of Carboxylic Acids Adsorption and Enolization on Monoclinic Zirconia Surfaces. The Journal of Physical Chemistry C, 115(32), 16012-16018. doi:10.1021/jp203381hJackson, M. A., & Cermak, S. C. (2012). Cross ketonization of Cuphea sp. oil with acetic acid over a composite oxide of Fe, Ce, and Al. Applied Catalysis A: General, 431-432, 157-163. doi:10.1016/j.apcata.2012.04.034Plint, N. ., Coville, N. ., Lack, D., Nattrass, G. ., & Vallay, T. (2001). The catalysed synthesis of symmetrical ketones from alcohols. Journal of Molecular Catalysis A: Chemical, 165(1-2), 275-281. doi:10.1016/s1381-1169(00)00445-3Randery, S. (2002). Cerium oxide-based catalysts for production of ketones by acid condensation. Applied Catalysis A: General, 226(1-2), 265-280. doi:10.1016/s0926-860x(01)00912-

Striatula (Hyacinthaceae, Urgineoideae), a new genus from South Africa and southern Namibia

Within the framework of the taxonomic revision of subfamily Urgineoideae of Hyacinthaceae, we here describe the new genus Striatula from South Africa and southern Namibia. Striatula is at first sight related to Rhadamanthus species, but can be easily distinguished by the one or two flat, ovate to elliptic, sulcate leaves which are appressed to the ground. This genus includes Rhadamanthus platyphyllus, a species native to the Western, Eastern and Northern Cape Province of South Africa, and the more recently described Drimia oliverorum from Namibia. A morphological description for Striatula is presented, including the most important characteristics and the necessary new combinations.This work was partly supported by the University of Graz (Austria), Fundación Ramón Areces (Spain), H2020 Research and Innovation Staff Exchange Programme of the European Commission, project 645636: ‘Insect-plant relationships: insights into biodiversity and new applications’ (FlyHigh), the grant ACIE18–03 UAUSTI18–02 from the University of Alicante (Spain)

Triandra pellabergensis (Hyacinthaceae subfam. Urgineoideae), a new genus and species from Pella se Berge, Northern Cape Province, South Africa

Within the framework of a taxonomic revision of subfamily Urgineoideae based on morphological, genetic and phytogeographic data covering numerous samples from its whole range of distribution, we here describe a new genus and species from Pella se Berge in northwestern South Africa. Triandra gen. nov. is easily characterized by the absence of stamens associated with the outer tepal whorl, therefore having only three stamens per flower, a character previously unknown in Hyacinthaceae. Triandra pellabergensis sp. nov. produces hypogeal bulbs with filiform proteranthous leaves, spurred bracts, lax racemes with few, nodding, nocturnal flowers and erect capsules with the withered tepals persisting atop. The new species resembles Urginea revoluta in general morphology, although this latter species has six stamens per flower, a different seed morphology, a distinct phytogeographic pattern, and a distant phylogenetic relationship. A complete morphological description is presented for the new genus and species, including data on its biology, ecology and distribution.This work was partly supported by H2020 Research and Innovation Staff Exchange Programme of the European Commission, project 645636: ‘Insect-plant relationships: insights into biodiversity and new applications’ (FlyHigh), and the grants ACIE18–03 UAUSTI18–02 and UAUSTI19-08 from the University of Alicante

A taxonomic revision of Tenicroa (Hyacinthaceae, Urgineoideae) – including four new species and two new combinations

Within the framework of a taxonomic revision of Hyacinthaceae subfamily Urgineoideae (Asparagaceae tribe Urgineeae) combining morphological and genetic data from numerous samples across its whole range of distribution, we here present a taxonomic revision of Tenicroa. Species of Tenicroa have a very intricate history and therefore, unlike many others, they have been placed by time in eight different genera. Tenicroa is characterized by having (mostly) synanthous leaves and sheathing cataphylls with raised darker transversal ridges, diurnal stellate flowers with white tepals having a distinct narrow, reddish-brown or greenish band, subbasifixed anthers, and the ovary elliptic-oblong to oblong, with an elongate, deflexed and often sigmoid style, and a papillate stigma. In this context, we here describe four new species (T. applanata, T. fibrosa, T. namibensis, T. polyantha) and present two new combinations (T. flexuosa, T. unifolia) in this genus. An identification key is provided for the 12 accepted species in the genus.This work was partly supported by the University of Graz (Austria), Fundación Ramón Areces (Spain), H2020 Research and Innovation Staff Exchange Programme of the European Commission, project 645636: ‘Insect-plant relationships: insights into biodiversity and new applications’ (FlyHigh), the grant ACIE18–03, UAUSTI18–02 and UAUSTI19–08 from the University of Alicante (Spain)

Agência, identidade e imaginação em uma escola primária urbana no sul do México

This paper presents an ethnographic study of two studentteachers in a Mexican public primary school in a fifth-grade English-asa-Foreign-Language classroom. Typical of classroom ethnography, this study incorporates systematic observation, description, micro-analysis of events, and discourse analysis. Utilizing a sociocultural perspective as a theoretical framework, the activities created by the two student-teachers are contrasted to the exercises and tasks prescribed in the official textbook. The analysis reveals that although the official textbook reflected a traditional, transmission-oriented pedagogy, the two student-teachers were able to adopt a socio constructivist and transformative teaching approach. They created activities that enabled their learners to work together through a variety of modes and to participate in a wide range of tasks that were relevant to their worlds beyond the classroom. Key words: sociocultural theory, ethnography, identity, second language education.Este artigo apresenta um estudo etnográfico das praticas pedagógicas de duas estagiárias em uma classe de inglês de quinta série em uma escola pública mexicana. Típico da etnografia de sala de aula, este estudo incorpora a observação sistemática, descrição, microanálise de eventos, e análise do discurso. Utilizando uma perspectiva sociocultural como referencial teórico, as atividades criadas pelas duas estagiárias são contrastadas com os exercícios prescritos pelo livro-texto oficial. A análise revela que, embora o livro-texto refletisse uma orientação pedagógica tradicional de transmissão, as duas estagiárias conseguiram adotar uma forma de ensino sócio-construtivista e transformadora. Elas criaram dinâmicas que possibilitaram a seus alunos trabalhar juntos através de diversas modalidades e de participar de várias atividades relevantes aos seus mundos fora da sala de aula. Palavras-chaves: teoria sociocultural, etnografia, identidade, ensino de línguas estrangeiras