Search results for "AYA"
showing 10 items of 358 documents
¿Por qué la literatura?
2021
In poetry, as well as in a good part of prose works, the rhythm of words is the music that governs reason and emotion. Literature occupies an important place in my creation. In this article I describe the different procedures in which I configure its presence in my music and the main themes in four of my works: Envoi, Como el viento, Maya and Transmutación.
Polysaccharide remains in Maya mural paintings: is it an evidence of the use of plant gums as binding medium of pigments and additive in the mortar?
2020
A number of monosaccharides characteristic of plant gums were found in paint layers and preparation layers of samples of Maya mural paintings of 10 archaeological sites located in Campeche and Yucatan regions. This finding opens the question about the deliberate use of these organic polymers as additives for improving workability and mechanical properties in the preparation layer mortar and conferring cohesion to the pigments in the paint layer. The study performed by GC-MS has confirmed the presence, in significant amounts, of a series of monosaccharides, being glucose and mannose between the most abundantly found. Nevertheless, the low amount present in most of the samples hindered the qu…
Popoya: historia de un poblado maya
2009
Traduzione della monografia in italiano
Arte en piedra tallada. La lítica del asentamiento urbano maya de La Blanca, Petén, Guatemala
2014
La presente tesis doctoral se centra en el estudio de los objetos de la cultura material asociados a las industrias lítica, ósea y malacológica hallados en La Blanca, un asentamiento urbano maya situado en el Departamento de El Petén, en Guatemala, en las Tierras Bajas Mayas del Sur, cuyo período de ocupación más significativo se desarrolló en el Clásico Tardío a Terminal y la transición al Postclásico Temprano. Los objetos de la cultura material constituyen una parte del registro arqueológico cuyo valor como fuente de información ha sido obviada en numerosas ocasiones en el área maya y para la que no existía una metodología de estudio claramente definida. Es por ello que desde el inicio de…
The link between independent acquisition of intracellular gamma-endosymbionts and concerted evolution in Tremblaya princeps
2015
Many insect species establish mutualistic symbiosis with intracellular bacteria that complement their unbalanced diets. The betaproteobacterium "Candidatus Tremblaya" maintains an ancient symbiosis with mealybugs (Hemiptera: Pseudococcidae), which are classified in subfamilies Phenacoccinae and Pseudococcinae. Most Phenacoccinae mealybugs have "Candidatus Tremblaya phenacola" as their unique endosymbiont, while most Pseudococcinae mealybugs show a nested symbiosis (a bacterial symbiont placed inside another one) where every "Candidatus Tremblaya princeps" cell harbors several cells of a gammaproteobacterium. Genomic characterization of the endosymbiotic consortium from Planococcus citri, co…
Mealybugs nested endosymbiosis: going into the 'matryoshka' system in Planococcus citri in depth.
2013
Abstract Background In all branches of life there are plenty of symbiotic associations. Insects are particularly well suited to establishing intracellular symbiosis with bacteria, providing them with metabolic capabilities they lack. Essential primary endosymbionts can coexist with facultative secondary symbionts which can, eventually, establish metabolic complementation with the primary endosymbiont, becoming a co-primary. Usually, both endosymbionts maintain their cellular identity. An exception is the endosymbiosis found in mealybugs of the subfamily Pseudoccinae, such as Planococcus citri, with Moranella endobia located inside Tremblaya princeps. Results We report the genome sequencing …
Molecular evidence for ongoing complementarity and horizontal gene transfer in endosymbiotic systems of mealybugs
2014
[EN] Intracellular bacterial supply of essential amino acids is common among sap-feeding insects, thus complementing the scarcity of nitrogenous compounds in plant phloem. This is also the role of the two mealybug endosymbiotic systems whose genomes have been sequenced. In the nested endosymbiotic system from Planococcus citri (Pseudococcinae), “Candidatus Tremblaya princeps” and “Candidatus Moranella endobia” cooperate to synthesize essential amino acids, while in Phenacoccus avenae (Phenacoccinae) this function is performed by its single endosymbiont “Candidatus Tremblaya phenacola.” However, little is known regarding the evolution of essential amino acid supplementation strategies in oth…
Experimental and thermodynamic constraints on mineral equilibrium inpantelleritic magmas
2020
Abstract Crystallization experiments on two pantellerites from Pantelleria, Italy, provide new evidence for the relationships between mineral phases in pantelleritic rocks as well as the influence of temperature and redox conditions on mineral assemblages. Experiments were performed at 1 kbar with temperature ranging between 750–900°C, and fluid saturation conditions with XH2O (=H2O/H2O+CO2) between 0 and 1. Redox conditions were fixed at, or slightly below, the FMQ buffer. Results show that at temperature of 900 °C pantelleritic magmas are well above the liquidus regardless their water content; we also observed a decrease in liquidus temperature (800°C) with increasingly reducing condition…
Morphological evolution and ecological diversification of the forest-dwelling poppies (Papaveraceae: Chelidonioideae) as deduced from a molecular phy…
1999
Sequences of the ITS region of nrDNA were analyzed for the seven genera of Papaveraceae subf. Chelidonioideae s.str. Three major clades can be recognized. These are 1.Chelidonium/Hylomecon/Stylophorum, 2.Eomecon/Sanguinaria, and 3.Bocconia/Macleaya. The monophyly of genera in the first of these three clades is doubtful, and clades two and three are sister to each other. Use of the ITS phylogeny of the subfamily to trace its morphological and ecological evolution shows that morphological change is concentrated in theBocconia/Macleaya clade, and probably related to the evolution of wind-pollination from insect-pollination in these two genera after habitat shift.
On the synonymization of Acaulon longifolium Herrnst. & Heyn with Acaulon fontiquerianum Casas & Sérgio (Pottiaceae)
2021
During bryological work conducted in the Sharon plane region (Israel), a colony of Acaulon Müll. Hal. was discovered. The plants showed morphological affinities both to A. longifolium Herrnst. & Heyn and A. fontiquerianum Casas & Sérgio depending on the floras used for their identification which challenged their recognition as separate species. In order to solve this taxonomic dilemma, we conducted a detailed morphological characterization of the two species based on representative samples. The micromorphological study of vegetative, sporophytic and spore traits revealed the large overlap of range values between both species. Both species showed the characteristic combination of morphologic…