Search results for "Fern"
showing 10 items of 163 documents
Mediterranean island biogeography: Analysis of fern species distribution in the system of islets around Sicily
2011
The aim of this article was to test the way in which geographical factors influence island floras in the Mediterranean basin, using ferns as target organisms, and the islands surrounding Sicily as location. A matrix with presence/absence data concerning fern taxa in the 16 islands studied was compiled. Cluster analysis, principal co-ordinates analysis (PCoA), principal components analysis (PCA) and a Bayesian analysis were performed. For each island, the total number of fern taxa was regressed against three factors: island area, island elevation and isolation. All the analyses pointed to affinities between islands according to their different geological composition, independently from their…
Nediferencējamu funkciju optimizācijas problēmas
2021
Bakalaura darba nolūks ir izpētīt optimizācijas metodes nediferencējamām funkcijām, lai veiksmīgi spētu tās pielietot dažādu problēmu risināšanā. Lielākoties darbs tiek balstīts uz trīs optimizācijas metodēm, tas ir, gradienta metodi, saišķa metodi un metodi, kuras pamatā nediferncējamu funkciju aizstāj ar diferencējamu. Darba gaitā apskatītās risināšanas tehnikas tiks aprakstītas gan teorētiski, gan arī parādīti prakstiski piemēri ar programmā Wolfram Mathamatica veidotiem grafikiem. Ir aprakstītas metožu pielietošanas iespējas un arī to trūkumi. Bakalaura darbā tiks iepazīstināts ar optimizācijas metožu vēsturi, minēti to pielietojumi dažādās profesionālajās sfērās, kā arī aprakstīti opti…
The extrabasinal elements in Lower Pennsylvanian floras of the Maritime Provinces, Canada: Description of Adiantites, Pseudadiantites and Rhacopterid…
2021
Adiantites adiantoide s (Lindley and Hutton) Kidston, Pseudadiantites sessilis (Roehl) Gothan and Pseudadiantites rhomboideus (Ettingshausen) comb. nov. are figured and described as well as Rhacopteridium speciosum (Ettingshausen) Hirmer, as part of a revision of lower Pennsylvanian floras of Nova Scotia. These species show a foliar branching structure which is described as "pseudopinnate" as against the fully planated pinnate structure of the Palaeozoic fern and pteridosperm fronds. Their systematic affinity is unknown. A discussion is presented of the genera A diantites, Pseudadiantites, Aneimites , Palaeopteridium , and Triphyllopteris , and the problematic nature of the history of Adian…
La construcción ideológica de la Restauración en Nueva España (1814-1816)
2020
La vuelta de Fernando VII en 1814 a la península y el golpe de Estado por el que procedió a anular la Constitución de Cádiz no supusieron, a ambos lados del Atlántico, un retorno a la situación previa a la crisis de 1808. Este trabajo examina dicho problema en el virreinato de la Nueva España desde el ámbito de los discursos para el periodo que transcurre entre 1814 y 1816. Para ello se relacionan tres perspectivas. En primer lugar, se confrontan algunos de los distintos proyectos que se plantearon dentro del absolutismo para efectuar la Restauración. Seguidamente, examinamos aquellos componentes teóricos que los intelectuales de la contrarrevolución utilizaron para legitimarla. Este proyec…
M. A. CORONEL RAMOS, Juan Luis Vives. El humanista y su entorno, Institució Alfons el Magnànim, Valencia, 2017. [ISBN 978-84-7822-702-0]
2019
Current distribution of Pilularia globulifera L. in Poland – changes of geographical range and habitat preferences
2013
<em>Pilularia globulifera </em>is a subatlantic European fern threatened with extinction. In Poland, it reaches the eastern border of its continuous range. Up to the end of the 20th century, it was observed here in 21 stands; only 2 of them existed by the second half of the century, so the species was categorized as critically endangered. Five new locations have been found in western and northwestern Poland during the last 10 years. Abundant and permanent populations grow in 3 locations, while 2 stands were ephemeral. All the current stands are situated in anthropogenic habitats with spontaneous vegetation, in oligotrophic to eutrophic waters. One of the new localities is about …
Un contrato de los Hernandos para la capilla de les Febres de la Seo de Xàtiva en 1511
2006
The contract dated 1511 signed by Fernando Llanos and Fernando Yáñez de la Almedina, Castillian painters known as “the Hernandos,” for the termination of an altarpiece in the chapel of the “Virgen de les Febres” is presented here. This chapel was founded in 1497 in the collegiate church of Jàtiva (Valencia) by Francisco de Borja, Bishop of Teano and Cardinal of Cosenza. Based on this document, a series of hypotheses are put forth concerning the trajectory and works of “the Hernandos” following their execution of the doors of the main altarpiece of the Cathedral of Valencia.<br><br>Se presenta el contrato firmado en 1511 por Fernando Llanos y Fernando Yañez de la Almedina, pintor…