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Las bibliotecas y los centros de documentación carecen de una guía metodológica para transformar sus datos RDF en grafos de conocimiento, lo que impide que puedan aprovechar las facilidades de esta herramienta en la búsqueda y recuperación de información. El artículo propone una metodología para la transformación de datos bibliográficos en grafos de conocimiento. Se presenta ANCORP, a partir del análisis de las técnicas de incrustación, limpieza y chequeo de grafos de conocimiento. Esta metodología se divide en dos partes: la parte 1, dedicada a la construcción del grafo de conocimiento, y la parte 2, dedicada a resolver los procesos de recuperación de información. Con la implementación de la metodología se corroboran saltos cualitativos en la recuperación de información y en la calidad de los datos(AU)

Libraries and documentation centers haven't a methodology guide to transform their RDF data into knowledge graphs, which prevents them from taking advantage of the facilities of this tool in the search and retrieval of information. This methodology was proposed for the transformation of bibliographic data in knowledge graphs. ANCORP was presented from the analysis of the techniques of incrustation, cleaning and checking of knowledge graphs. This methodology was divided into two parts: part I dedicated to the construction of the knowledge graph, and part II dedicated to solving the processes of information retrieval. With the implementation of the methodology, qualitative leaps in the information retrieval and in the quality of the data are corroborated(AU)

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Islands have played a key role in understanding species formation ever since Darwin's work on the Galapagos and Wallace's work in the Malay Archipelago. Like oceanic islands, habitat 'islands', such as mountaintops and caves similarly may drive diversification. Here we examine patterns of diversification in the tailless whip spider genus Phrynus Larmarck, 1809 (Amblypygida: Phrynidae) a system that shows evidence of diversification under the influence of 'islands within islands'. We estimate phylogeographic history and measure genetic diversity among representatives of three nominal Phrynus species from epigean and cave systems of Puerto Rico and nearby islands. Data from five loci (mitochondrial 12S, 16S, Cox1; nuclear H3, 28S) were used to generate phylogenetic hypotheses and to assess species monophyly and phylogeographic relationships. Genetic divergences and population limits were estimated and assessed using the Geneious barcoding plugin and the genealogical sorting index. We find that mtDNA sequence divergences within each of the three Phrynus species range between 15% and 20%. Genetic divergence is structured at three spatial scales: among islands in a manner consistent with the GAARlandia hypothesis, among bedrock formations within Puerto Rico, and among caves within these formations. Every isolated cave system contains a unique mtDNA genetic lineage of Phrynus, with divergence among cave systems far exceeding that within. In some localities epigean specimens nest among cave taxa, in others caves are monophyletic. Remarkably, clades that show up to 20% mtDNA sequence divergence show little or no variation in the nuclear markers. We interpret this pattern as resulting from extreme conservation of our nuclear markers rather than male sex-biased dispersal, based on high conservation of 28S and H3 between our individuals and other amblypygid genera that are restricted to Africa. While this study includes but a tiny fraction of Caribbean caves, our findings suggest Phrynus may be much more diverse than hitherto thought, at least in terms of mtDNA diversity, and that the arthropod fauna of caves may represent a dimension of biodiversity that is yet to be discovered in the Caribbean biodiversity hotspot.

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Barriers persist in the development and delivery of effective cancer therapies to under-represented minority populations. In Puerto Rico, cancer is the second leading cause of death, yet cancer research awareness and training opportunities remain somewhat limited on the island. These limitations hinder progress toward decreasing the cancer health disparities that exist within the Puerto Rican population. The predominantly Hispanic population of Puerto Rico is the focus of a partnership between the Ponce Health Sciences University-Medical School and Ponce Research Institute (PHSU) in Ponce, Puerto Rico and the H. Lee Moffitt Cancer Center in Tampa, Florida. The Partnership goals are to reduce these barriers through an integrated, multipronged approach of training and education alongside outreach and research components. This report describes the approaches, successes and challenges of enhancing clinical cancer research capacity on the island and the unique challenges of a partnership between two institutes physically separated by long distances. Once fully developed this model may be exportable to other Latin American countries where the need is even greater.

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The design and synthesis of fullerene-steroid hybrids by using Prato's protocol has afforded new fullerene derivatives endowed with epiandrosterone, an important naturally occurring steroid hormone. Since the formation of the pyrrolidine ring resulting from the 1,3-dipolar cyloaddition reaction takes place with generation of a new stereogenic center on the C2 of the five-membered ring, the reaction proceeds with formation of a diastereomeric mixture [compounds 6 and 7 in 70:30 ratio, 8 and 9 in 26:74 ratio (HPLC)] in which the formation of the major diasteroisomers 6 and 9 is consistent with an electrophilic attack of [60]fullerene on the Re face of the azomethine ylide directed by the steroidic unit. The chiroptical properties of these conjugates reveal typical Cotton effects in CD spectra that have been used to assign the absolute configuration of the new fulleropyrrolidines. The electrochemical study of the new compounds reveals the presence of four quasi-reversible reduction waves which are cathodically shifted in comparison with the parent C60, thus ascertaining the proposed structures.

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We report a facile protocol to obtain 22-substituted furostans and pseudosapogenins in high yields from (25R)- and (25S)-sapogenins. This method involves the treatment of the sapogenin with acetic-trifluoroacetic mixed anhydride and BF(3)·OEt(2) at room temperature, followed by the addition of a nucleophile (H(2)O, MeOH or KSeCN). In the case of 22-hydroxyfurostans, they can be transformed to pseudosapogenins by treatment with p-toluensulfonic acid.

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(1)H and (13)C NMR spectroscopic data for 5alpha-androstanes and halo-5alpha-androstanes with different substituents at positions C-3, C-9, C-11 and C-17 were examined and assigned by a combination of 1D and 2D NMR experiments. The substituent effects on the (13)C chemical shifts were compared with those of epi-androsterone, used as a reference compound. The coupling constants (n)J((19)F,(13)C) were measured for compounds 6, 8, 11 and 14.

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La concentración de calcio sérico ionizado es indispensable para el control del metabolismo celular y otros procesos biológicos. Diferentes factores tales como control hormonal, concentración de albúmina sérica y alteraciones hidro-electrolíticas pueden alterar las concentraciones del calcio sérico ionizado, que representa la forma libre y activa de este ión. En diferentes estados patológicos se puede observar una disminución del calcio sérico y es importante detectar y manejar tempranamente la hipocalcemia en el paciente críticamente enfermo.

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Se describe un método para la obtención de 9(11)-dehidrotigogenina a partir de hecogenina, técnica aislada de bulbos de azucena (Polianthes tuberosa) con elevado contenido de 9(11)- dehidrohecogenina. Se demuestra que la presencia de cantidades considerables del derivado insaturado en la hecogenina empleada no interfiere en la obtención de la 9(11)- dehidrotigogenina, según el esquema de síntesis que se propone. Se señala la eliminación directa del átomo de bromo en la posición 23 durante la reducción de Wolff-Kishner del grupo 12-cetónico(AU)

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