Ciencias básicas
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Recent Submissions
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Validación de un método para cuantificación de acetaminofén en tabletas de 500 mg por espectrofotometría ultravioleta para la prueba de uniformidad de contenido
(2016-07-07)El presente artículo contiene los detalles de la validación del método analítico para la cuantificación de acetaminofén, en este caso para aplicar a la prueba de uniformidad de contenido a tabletas de 500 mg, por la técnica ... -
Quantum symmetry groups of noncommutative spheres
(2001-08)We show that the noncommutative spheres of Connes and Landi are quantum homogeneous spaces for certain compact quantum groups. We give a general construction of homogeneous spaces which support noncommutative spin geometries. -
Quantum electrodynamics in external fields from the spin representation
(1994-07)Systematic use of the infinite-dimensional spin representation simplifies and rigorizes several questions in quantum field theory. This representation permutes "Gaussian" elements in the fermion Fock space, and is necessarily ... -
The metaplectic representation and boson fields
(1991-12)We construct explicitly the infinite-dimensional metaplectic representation and show how its use simplifies and rigorizes several questions in bosonic Quantum Field Theory. The representation permutes Gaussian elements in ... -
Síntesis de la feromona sexual de la polilla de la papa, Scrobipalpopsis Solanivora
(1988)Se sintetizó el acetato (E) -3- dodecenilo, atrayente sexual de la polilla de la papa (Scrobipalpopsis solanivora), utilizando dos procedimientos: una ruta acetilénica y mediante la condensación de Knoevenagel. -
Regiospecific Palladium-Catalyzed Cross-Coupling Reactions Using the Operational Equivalent of 1,3-Dilithiopropyne
(2020)A regiospecific palladium-catalyzed cross-coupling reaction using the operational equivalent of the dianion 1,3-dilithiopropyne, with aromatic iodides is reported. This reaction gives high yields of 1-propyn-1-yl-benzenes ... -
A new methodology for the synthesis of δ-substituted α,β-unsaturated δ-lactones
(2020)A new protocol for the synthesis of δ-substituted-α,β-unsaturated δ-lactones was developed. Selective reaction of 1,3-dilithiopropyne with ketones, followed by addition of ethyl chloroformate formed ethyl 5-[(ethoxycarbo ... -
A new and efficient synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone component of the tomato leafminer Tuta absoluta
(2018)An efficient synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone component of the tomato leafminer moth, Tuta absoluta, was accomplished. The synthesis started with but-3-yn-1-ol and gave an ... -
Synthesis of N-[3-(prop-1-yn-1-yl)phenyl] benzene sulfonamide and Determination of its Antibacterial Activity
(2019-07-25)The synthesis of N-[3-(prop-1-yn-1-yl)phenyl] benzenesulfonamide was performed and its antibacterial activity against Staphylococcus aureus and Escherichia coli was determined. Minimalinhibitory concentrations (MIC) of ... -
Design and synthesis of n-[3-(3-oxoprop-1-yn-1-yl) phenyl] benzene sulfonamide: a highly active antimicrobial compound
(2019)The synthesis of the highly active compound N-[3-(3-oxoprop-1-yn-1-yl)phenyl] benzene sulfonamide was performed and its activity against Gram (+), Gram (-), mold and yeast was determined. -
Desarrollo de un sistema de modificación genética en caoba (Swietenia macrophylla King) mediante la evaluación de la expresión transitoria y estable del gen reportero GUS
(2023)La caoba (Swietenia macrophylla King) (Meliaceae) es una especie forestal muy valiosa y comercializada a nivel mundial, pero su sobreexplotación ocasionó que se convirtiera en una especie amenazada (Apéndice II, CITES). ... -
Anolis insignis (Decorated anole). Predation attempt
(2019)Two jays attacking an A. insignis on a liana 10 m above the ground. -
Frequency and synchronisation features of a highly overlapped duet changes according to the context
(2019)Territorial defence and maintaining contact are two hypotheses of duet functions. Nevertheless, the acoustic characteristics of duets in these contexts have been poorly quantified. This work aimed to compare the spectrotemporal ... -
Geographic variation in the duets of the Rufous-naped Wren (Campylorhynchus rufinucha) complex
(2020)Acoustic signals used in animal communication play a key role in mate attraction, species recognition, and territory defense. Variation in acoustic signals may reflect population structure, lack of gene flow, and phylogenetic ... -
Territory size, population density, and natural history of Cabanis’s Ground Sparrow, an endemic species found in urban areas
(2021)Worldwide urban expansion threatens biodiversity inhabiting the original natural environments now being transformed, especially range-restricted species. Here, we provide estimates of population density, population size, ... -
Intruder familiarity and not duet similarity influences the territory defense in a year-round territorial bird species
(2022)To avoid unnecessary energy expenditures in territorial defense, many species (e.g., insects, amphibians, birds, and mammals) have developed the capability to distinguish between different intruder types using visual, ... -
The use of artificial substrate and materials for nest building in 2 ground-finches (Geospiza spp.) under human-altered conditions
(2021)Urbanization is one of the main problems for biodiversity around the world, associated with a decrease of natural habitats and its resources. In contrast, urbanization can also provide new resources that could be used by ... -
A test of the Acoustic Adaptation Hypothesis in three types of tropical forest: degradation of male and female Rufous-and-white Wren songs
(2016)Many animals produce complex vocalizations that show pronounced variation between populations. The Acoustic Adaptation Hypothesis helps to explain this variation, suggesting that acoustic signals are optimized for transmission ... -
First record of Lesson's Seedeater Sporophila bouvronides in Costa Rica
(2022)We report the first record of Lesson’s Seedeater Sporophila bouvronides, a South American species, in Costa Rica. It was seen at Tortuguero, in the lowlands of north-east Costa Rica in June 2022. The record is perhaps ... -
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 ...
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