1,720,994 research outputs found
Morphoanatomy and ethnobotany of rhizome, stem and scape of «kapi’i kati» Kyllinga odorata (Cyperaceae) and its substituents in and around Asunción del Paraguay.
Get PDFSe presenta la morfoanatomía del “kapi’i kati” K. odorata Vahl. y sus sustituyentes K. brevifolia Rottb., K. vaginata Lam. y Scleria distans Poir (Cyperaceae) comercializadas como especies medicinales en los principales mercados de Asunción y Gran Asunción, Paraguay. Se establece una clave para la identificación de las mismas.The morphoanatomy of “kapi’i kati” K. odorata Vahl. (Cyperaceae) and its substituents K. brevifolia Rotbb., K. vaginata Lam. and Scleria distans Poir, commercialized as medicinal species in in the major markets of Asunción and Gran Asunción del Paraguay. Providing a key for their identification.Fil: González, Yenny. Universidad Nacional de Asunción; ParaguayFil: Mercado, Maria Ines. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Degen, Rosa. Universidad Nacional de Asunción; ParaguayFil: Ponessa, Graciela Inés. Fundación Miguel Lillo; Argentin
Variability in sesquiterpene lactones from the leaves of yacon (Smallanthus sonchifolius) accessions of different geographic origin
No full textThe sesquiterpene lactones (STLs) content of glandular trichomes from the leaves of twenty-five yacon (Smallanthus sonchifolius, Asteraceae) accessions, obtained along a latitudinal gradient from Ecuador to northwest Argentina, was characterized by gas chromatography/mass spectroscopy (GC/MS). While accessions from Ecuador, Bolivia and Argentina proved to be very chemoconsistent, significant variation was found in quantitative composition of STLs from accessions in central Peru, the probable region of origin for the species.Fil: Mercado, Maria Ines. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional.; ArgentinaFil: Coll Araoz, Maria Victoria. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional.; ArgentinaFil: Manrique, Ivan. Universidad Nacional de Cajamarca; PerúFil: Grau, Alfredo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional.; ArgentinaFil: Catalan, Cesar Atilio Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin
New Acyclic Diterpenic Acids from Yacon (Smallanthus sonchifolius) Leaves
No full textTwo new acyclic diterpenoids, smaditerpenic acid E (1a) and F (2a), along with nineteen melampolide-type sesquiterpene lactones, six of them not previously reported in yacon, were isolated from the methylene chloride leaf rinse extract. Their structures were elucidated from 1D and 2D NMR experiments and gas chromatography coupled to mass spectrometry.Fil: Mercado, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Coll Araoz, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentina. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Grau, Alfredo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Catalan, Cesar Atilio Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Characterization of Feeding Injuries Caused by Ceresa nigripectus Remes Lenicov (Hemiptera: Membracidae) on Alfalfa Stems
Get PDFPiercing-sucking insects cause mechanical and physiological injury to plants. Ceresa nigripectus Remes Lenicov is a pest of alfalfa in subtropical regions of South America and a carrier of the ArAWB phytoplasma. The aim of this study was to determine the feeding habits of this treehopper and to describe the effects of the feeding injuries on stem vascular tissues in alfalfa. Adults and nymphs of C. nigripectus inserted their stylets repeatedly girdling the stem. One week after feeding, alfalfa stems exhibited numerous feeding canals with salivary deposits, most of which reached the phloem. Two weeks after feeding, cortex and phloem cells next to the salivary sheath collapsed, mature tracheal elements became sparse and appeared with an increased cross-section area, and phenolic compounds increased in cells and cell walls compared to undamaged plants. Three weeks after feeding, an annular callus, formed by abnormal cell division and hypertrophy of preexisting cortex and vascular cambium cells, appeared immediately above the stem girdle. Parenchyma cells from the outer layers of the callus differentiated to form secondary anomalous amphicribal bundles in the wound. The aerial parts above the stem girdle eventually withered and died.Fil: Perez Grosso, Tomas. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mercado, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucuman. Facultad de Cs.naturales E Instituto Miguel Lillo. Departamento de Morfología Fisiología y Taxonomia Vegetal. Laboratorio de Anatomia Vegetal; ArgentinaFil: Ponesa, G. I.. Universidad Nacional de Tucuman. Facultad de Cs.naturales E Instituto Miguel Lillo. Departamento de Morfología Fisiología y Taxonomia Vegetal. Laboratorio de Anatomia Vegetal; Argentina. Fundación Miguel Lillo; ArgentinaFil: Conci, Luis Rogelio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Patología Vegetal; ArgentinaFil: Virla, Eduardo Gabriel. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Morphoanatomy and histochemistry of stem and leaves of Araujia odorata (Apocynaceae) from Tucumán (Argentina)
Get PDFAraujia odorata (Hook. & Arn.) Fontella & Goyder (Apocynaceae, Asclepiadoideae), es un sub-arbusto voluble, 3-5 m de altura, crece en Argentina (de Mendoza a Jujuy), Brasil, Paraguay y Uruguay. El látex, raíces y hojas son utilizados como galactógeno, analgésico, en gárgaras para caries e infl amaciones de garganta, anti-verrucoso, contra la difteria y como goma de pegar. El objetivo fue realizar una descripción morfo-anatómica de tallos y hojas e identifi car compuestos en los conductos laticíferos de cinco poblaciones de A. odorata de Tucumán. Las poblaciones estudiadas presentan hojas isolaterales anfi estomáticas, cutícula estriada, células epidérmicas de paredes anticlinales rectas, estomas braqui, anomo y anfi ciclocíticos, tricomas eglandulares uniseriados ornamentados. Nervio medio con haz único bicolateral con conductos laticíferos en fl oema y parénquima circundante. Tallo circular con epidermis papilada, tricomas eglandulares, colénquima sub-epidérmico, clorénquima radial, eustela anfifl oica, grupos de fi bras no lignifi cadas y médula amplia. A nivel de córtex presenta drusas y en fl oema y médula conductos laticíferos no articulados raramente ramifi cados, conteniendo lípidos, almidón y compuestos fenólicos. Se detectaron compuestos fenólicos en el parénquima radial, alcaloides en colénquima subepidérmico, aceites esenciales en células acompañantes estomáticas, epidérmicas y parénquima radial; y triterpenos esteroideos en colénquima subepidérmico y parénquima radial.Fil: Mercado, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Instituto de Morfologia Vegetal ; Direccion de Botanica ; Fundacion Miguel Lillo;Fil: Alvarez, María de Los Ángeles. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Ponessa, Graciela Ines. Instituto de Morfologia Vegetal ; Direccion de Botanica ; Fundacion Miguel Lillo;XXXVI Jornadas Argentinas de BotanicaMendozaArgentinaSociedad Argentina de Botánic
Intraspecific variation of sesquiterpene lactones associated to a latitudinal gradient in Smallanthus macroscyphus (Heliantheae: Asteraceae)
Get PDFAccording to theory, variation in plant secondary metabolism against herbivores is driven by variation in biotic and abiotic conditions interacting with plants genotype to determine the expression of resistance traits. Particularly, it has been long postulated that plants growing along latitudinal gradients experience changes in biotic and abiotic interactions, specifically leading to a decrease of plant toxicity towards the poles. We tested this hypothesis using the asteraceous species Smallanthus macroscyphus. Smallanthus species are known to contain sesquiterpene lactones (STLs), bitter compounds with a broad spectrum of biological activities, including deterrence to herbivores. S. macroscyphus showed a decrease in chemical diversity of STLs when investigating populations growing from the tropical regions to less tropical ones. Populations from lower latitudes were found to be more chemically diverse with enhydrin, uvedalin and fluctuanin as main components, while populations southward were chemically fairly uniform, with polymatin A as the main and largely dominant STL. The STL chemistry of S. macroscyphus is in agreement with the hypothesis that plants of tropical forests have a greater diversity of secondary metabolites when compared to their temperate counterparts.Fil: Coll Araoz, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucuman. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Mercado, Maria Ines. Fundación Miguel Lillo; ArgentinaFil: Grau, Alfredo. Universidad Nacional de Tucuman. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Catalan, Cesar Atilio Nazareno. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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