Browsing Ciencias básicas by Title
Now showing items 198-217 of 3100
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Alkaloid contents in members of Lycopodiales
(2001)The composition of alkaloids in fifteen species that belong to the Lycopodiales, which grow wild in Costa Rica were analysed by gas chromatography coupled with mass spectrometry. Several alkaloids were identified, ... -
Alkaloids from Crinum erubescens Aiton
(2016-09)Eight alkaloids have been identified from fresh leaves of Crinum erubescens (Amaryllidaceae) collected in Costa Rica. The alkaloid 1-epidemethylbowdensine, detected by means of GC–MS as part of a global Amaryllidaceae ... -
All-offspring natal philopatry in a Neotropical bat
(2011-11)Natal dispersal is a strategy employed by individuals to avoid reproducing with close relatives. In most bats, incestuous matings are prevented by the departure of one sex; thus, all-offspring philopatry has rarely been ... -
Allometry and stilt root structure of the Neotropical palm Euterpe precatoria (Arecaceae) across sites and successional stages
(2010)The lack of secondary meristems shapes allometric relationships of the palms, infl uencing species segregation according to their capacity to adjust form and function to spatial and temporal changes in environmental ... -
La alometría estática de estructuras bajo selección sexual.
(2012-04-24)El proyecto se diseñó para determinar la alometría del tamaño de las estructuras genitálicas y otras no-genitálicas en varias especies de Coleoptera. El informe es una lista de las publicaciones generadas a partir de la ... -
Alta capacidad de autofecundación y baja visitación de polinizadores en la epífita polinizada por colibríes Pitcairnia heterophylla (Bromeliaceae) en un bosque montano en Costa Rica
(2017)La subfamilia Pitcairnioideae es la segunda más diversa de las bromelias (Bromeliaceae), un grupo exclusivo de la región Neotropical. Las bromelias pitcairnioideas poseen rasgos florales que se asume promueven el exo-cruzamiento ... -
Alternative approaches to determine the efficiency of biomixtures used for pesticide degradation in biopurification systems
(2018)Biopurification systems were developed for the biological treatment of pesticide-containing wastewaters originated from agricultural production. They are aimed at reducing point-source contamination related to the ... -
Alternative principal components regression procedures for dendrohydrologic reconstructions
(2000-11)Streamflow reconstruction using tree ring information (dendrohydrology) has traditionally used principal components analysis (PCA) and stepwise regression to form a transfer function. However, PCA has several procedural ... -
Ammonium and phosphate removal using batch laboratory cultures by microalgae and cyanobacteria isolated from Costa Rica water bodies
(2018)This research analyzed three green microalgae (Scenedesmus sp., Chlamydomonas sp., and Chlorella sp.) and two cyanobacteria (Synechocystis sp. as unicellular strain and Nostoc sp. as filamentous strain) native from Costa ... -
Amphibians and Reptiles of the Tirimbina Biological Reserve: a baseline for conservation, research and environmental education in a lowland tropical wet forest in Costa Rica
(2020-11-30)The Tirimbina Biological Reserve is located in the lowlands on the Atlantic versant of Costa Rica. This study provides an updated comprehensive herpetofauna species list and summarizes the results of all the herpetofauna ... -
An 800-year high-resolution black carbon ice core record from Lomonosovfonna, Svalbard, Atmos
(2018)Produced by the incomplete combustion of fossil fuel and biomass, black carbon (BC) contributes to Arctic warming by reducing snow albedo and thus triggering a snow-albedo feedback leading to increased snowmelt. Therefore, ... -
An adaptive choice of primal constrains for BDDC domain decomposition algorithms
(2016-12-12)An adaptive choice for primal spaces based on parallel sums is developed for BDDC deluxe methods and elliptic problems in three dimensions. The primal space, which forms the global, coarse part of the domain decomposition ... -
An augmented mixed–primal finite element method for a coupled flow–transport problem
(2015)In this paper we analyze the coupling of a scalar nonlinear convection-diffusion problem with the Stokes equations where the viscosity depends on the distribution of the solution to the transport problem. An augmented ... -
An eccentric new species of Stelis from Peru (Orchidaceae: Pleurothallidinae)
(2017)Stelis hualluapampensis, a new species from the cloud forests of Hualluapampa, in the Tayacaja province, Peru, is described and illustrated. Information on its distribution, habitat, phenology, and conservation status, ... -
An improved stereospecific synthesis of (Z,E)-9, 11, 13-Tetradecatrienal. Sex pheromone component of Stenoma cecropia
(2000)(Z,E)-9,11,13-tetradecatrienal, a pheromone component of Stenoma cecropia, was prepared in 61% overall yield from 1-nonyne. The synthesis involved two palladium-catalyzed cros-couplings to afford a 1,3-dien5-yne, which was ... -
An Improved stereospecific synthesis of (Z,E)-tetradecadienal. Sex pheromone component of Stenoma cecropia
(1998)(Z,E)-9, 11-Tetradecadienal, a sex pheromone component of Stenoma cecropia, has been synthesized in 7 steps and 61% overall yield. The synthesis utilized a palladium catalyzed coupling between 9-decynyl tert-butyldinethylsilyl ... -
An Insect Herbivore Microbiome with High Plant Biomass-Degrading Capacity
(PLoS Genetics. September 2010. Volume 6, Issue 9. e1001129, 2010-09)Herbivores can gain indirect access to recalcitrant carbon present in plant cell walls through symbiotic associations with lignocellulolytic microbes. A paradigmatic example is the leaf-cutter ant (Tribe: Attini), which ... -
An overlapping preconditioner for 2D virtual problems posed in H(rot) with irregular subdomains
(2022)We present a two-level overlapping Schwarz preconditioner for problems posed in H(rot) in two dimensions, that extends previous methods for Nédélec elements (triangular meshes) to general polygonal partitions (virtual ... -
An overlapping Schwarz method for virtual element discretizations in two dimensions
(2019)A new coarse space for domain decomposition methods is presented for nodal ellipticproblems in two dimensions. The coarse space is derived from the novel virtual elementmethods and therefore can accommodate quite irregular ... -
An overview of bird records committees in the Neotropics
(2018)Neotropical bird records committees have been growing in numbers, remit and prominence in recent years. This feature – by members of those committees – explains how and why committees were established and encourages birders ...