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Mostrando ítems 174-193 de 360

    • Fungi with history: Unveiling the mycobiota of historic documents of Costa Rica 

      Escudero Leyva, Efraín; Vieto Fonseca, Sofía; Avendaño Vega, Roberto; Rojas Gätjens, Diego; Agüero Gamboa, Paola; Pacheco Ureña, Carlos; Montero Villalobos, Mavis Lili; Chaverri Echandi, Priscila; Chavarría Vargas, Max (2022-06-12)
      Through nondestructive techniques, we studied the physicochemical characteristics and mycobiota of five key historic documents from Costa Rica, including the Independence Act of Costa Rica from 1821. We determined that for ...

    • Fusarium: more than a node or a foot-shaped basal cell 

      Willem Crous, Pedro; Lombard, Lorenzo; Sandoval Denis, ‪Marcelo; Seifert, Keith A.; Schroers, Hans Josef; Chaverri Echandi, Priscila; Gené Díaz, Josepa; Guarro Artigas, Josep; Hirooka, Yuuri; Bensch, Konstanze; Kema, Gert; Lamprecht, Sandra C.; Cai, Lei; Rossman, Amy Y.; Stadler, Marc; Summerbell, Richard C.; Taylor, John W.; Ploch, Sebastian; Visagie, Cobus Meyer; Yilmaz, Neriman; Frisvad, Jens Christian; Abdel-Azeem, Ahmed M.; Abdollahzadeh, Jafar; Abdolrasouli, Ali Reza; Akulov, Alexander; Alberts, Johanna Francina; Araújo, João P. M.; Ariyawansa, Hiran Anjana; Bakhshi, Mounes; Bendiksby, Mika; Ben Hadj Amor, A.; Bezerra, Jadson D. P.; Boekhout, Teun; Câmara, ‪Marcos Paz Saraiva; Carbia, Mauricio; Cardinali, Gianluigi; Castañeda Ruiz, Rafael Felipe; Celis Ramirez, Adriana Marcela; Chaturvedi, Vishnu; Collemare, Jérôme; Croll, Daniel; Damm‬, ‪Ulrike; Decock, Cony A.; de Vries, Ronald P.; Ezekiel, ‪Chibundu N.; Fan, ‪Xinlei; Fernández, Nicolás; Gaya, Ester; González, Cristian; Gramaje Pérez, David; Groenewald, Johannes Zacharias; Grube, Martin; Guevara Suarez, ‪Marcela; Gupta, Vijai Kumar; Guarnaccia, Vladimiro; Haddaji, A.; Hagen, Ferry; Haelewaters, Danny; Hansen, Karen; Hashimoto, Akira; Hernández Restrepo, ‪Margarita; Houbraken, Jos; Hubka, V.; Hyde, Kevin David; Iturriaga, Teresa; Jeewon, Rajesh; Johnston, Peter R.; Jurjević, Željko; Karalti, Iskender; Korsten, ‪Lise; Kuramae, ‪Eiko; Kušan, Ivana; Labuda, Roman; Lawrence, Daniel P.; Lee, H. B.; Lechat, Christian; Li, H. Y.; Litovka, Yulia A.; Maharachchikumbura, Sajeewa; Marin Felix‬, ‪Yasmina; Matio Kemkuignou, Blondelle; Matocec, N.; McTaggart, Alistair; Mlčoch, Patrik; Mugnai, Laura; Nakashima, Chiharu; Nilsson, R. Henrik; Noumeur, Sara Raouia; Pavlov, Igor N.; Peralta, M. P.; Phillips, Alan J. L.; Pitt, John L.; Polizzi, Giancarlo; Quaedvlieg, William; Rajeshkumar, K. C.; Restrepo Restrepo, Silvia; Rhaiem, Azza; Robert, J.; Robert, Vincent; Rodrigues, Anderson M.; Salgado Salazar, Catalina; Samson, Robert A.; Santos, A. C. S.; Shivas, Roger; de Souza Motta, Cristina Maria; Sun, Guang-Yu; Swart, Wijnand; Szoke, S.; Tan, Yu Pei; Taylor, Joanne; Taylor, ‪Paul W. J.; Vieira Tiago, Patrícia; Váczy, Kálmán Zoltán; van de Wiele, N.; van der Merwe, Nicolaas A.; Verkley, Gerard J. M.; Vieira, W. A. S.; Vizzini, Alfredo; Weir, Bevan; Wijayawardene, Nalin N.; Xia, Ji-Wen; Yañez Morales, Maria de Jesus; Yurkov, Andrey; Zamora Senoret, Juan Carlos; Zare, Rasoul; Zhang, Chunli; Thines, Marco (2021)
      Recent publications have argued that there are potentially serious consequences for researchers in recognising distinct genera in the terminal fusarioid clade of the family Nectriaceae. Thus, an alternate hypothesis, namely ...

    • Gaschromatographische Analyse des Samenfettes der mittelamerikanischen Fevillea Cordifolia (Cucurbitaceae) 

      Achenbach, Hans; Hefter Bübl, Ursula; Waibel, Reiner; Constenla Umaña, Manuel Arturo; Hahn, Horts (1992)
      The fat of the seeds of Fevillea cordifolia was extracted under exclusion of oxygen and light and then characterized by 13C-NMR in regard to the contained unsaturated acid moieties. The total fat was separated by HPLC to ...

    • General Chemistry Without Orbitals 

      Lamoureux Lamontagne, Guy; Ogilvie, John F. (2020)
      We illustrate the solutions of Schroedinger's equation for the hydrogen atom in coordinates of all four systems, and differentiate the applicability of orbitals in these four systems. We present reasons that future textbooks ...

    • Germacranolides and other constituents from ageratzna species 

      Tamayo Castillo, Giselle; Jakupovic, Jasmin; Bohlmann, Ferdinand; Rojas, A.; Castro Araya, Víctor H.; King, Robert M. (1988)
      The aerial parts of Ageratina anisochroma gave several thymol derivatives including five new ones, a hydroxypiperitol glucoside, some substituted benzyl benzoates and several germacranolides related to provincialin. From ...

    • Germacranolides from Mikania guaco 

      Rüngeler, Peter; Brecht, Volker; Tamayo Castillo, Giselle; Merfort, Irmgard (2001-03)
      Fourteen novel sesquiterpene lactones of the germacranolide type have been isolated from the aerial parts of Mikania guaco: six costunolide, two melampolide and six germacra-4-trans,10(14),11(13)-trien-12,6α-olide derivatives. ...

    • Granular Activated Carbon Treatment May Result in Higher Predicted Genotoxicity in the Presence of Bromide 

      Krasner, Stuart W.; Fen Lee, Tiffany Chih; Westerhoff, Paul; Fischer, Natalia; Hanigan, David; Karanfil, Tanju; Beita Sandí, Wilson; Taylor Edmonds, Liz; Andrews, Robert C. (2016-07-28)
      Certain unregulated disinfection byproducts (DBPs) are more of a health concern than regulated DBPs. Brominated species are typically more cytotoxic and genotoxic than their chlorinated analogs. The impact of granular ...

    • Grids II: Aromatic Acidity and Basicity 

      Lamoureux Lamontagne, Guy; Arias Álvarez, Carlos (2021)
      The effect of substituents on the acidity of benzoic acids and basicity of anilines has been organized in grids to demonstrate the inductive and resonance effects. The relation between structure and pKa is emphasized ...

    • Grids III: Hydrogen Bridges in Introductory Chemistry 

      Lamoureux Lamontagne, Guy; Chaves Carballo, Katherine; Arias Álvarez, Carlos (2021)
      Based on IUPAC recommendations for the definition of the hydrogen bond, a series of grids is presented to provide instructors of introductory chemistry courses with visual examples of H-bridged systems. The grids ...

    • Guía de lectura de la Base de Datos para el Estudio de Inteligencia Tecnológica y Científica del Cannabidiol (CBD) 

      Varela Vásquez, Stefany; Alpízar Segura, Daniel (2023)
      El Excel cuenta con 3 hojas, donde la primera corresponde a Artículos Científicos, la segunda a Patentes y la última a CIP detalle, las cuales son las siglas para Código Internacional de Patentes. De esta manera, en cada ...

    • Guía de mediación pedagógica para aprendizajes comunitarios: comités de agua transfronte- rizos, Costa Rica - Nicaragua : pedagogía social, estrategias para la optimización del uso del agua para consumo humano en las comunidades de La Trocha e Isla Chica en los Chiles, Alajuela 

      Badilla Zamora, Isabel; Barrantes Jiménez, Kenia; Chacón Jiménez, Luz María; Fuentes Schweizer, Paola; Jiménez Corrales, Rafael; Morales Mora, Eric; Segura Esquivel, Sylvia; Solís Sánchez, Gabriela; Vargas Muñoz, Rigoberto; Villalobos Vega, Patricia (2021)
      El equipo de profesores y profesoras de la Universidad Nacional y la Universidad de Costa Rica que elaboró esta guía conforma el proyecto de extensión y acción social universitaria: “Pedagogía social: estrategias para la ...

    • Harnessing titanium dioxide surface toward novel functional materials 

      Solera Rojas, José Andrés; Rapp, Christin K.; Rivera Martínez, M. Cinthya; Pineda Cedeño, Leslie William (2015)
      The ever-increasing worldwide energy consumption has led the society to quest for novel and functional materials that can be used in the development of solar fuels to some extent lessen the dependence on fossil fuels. In ...

    • Heliangolides from Viguiera sylvatica 

      Tamayo Castillo, Giselle; Jakupovic, Jasmin; Bohlmann, Ferdinand; Castro Araya, Víctor H. (1989)
      The extract of the aerial parts of Viguiera sylvatica gave, in addition to known heliangolides, four new heliangolides related to 1-desoxyniveusin A and one to 11,13-dihydrofuroheliangolide as well as three guaianolides, ...

    • Heterogeneous Water Oxidation: Surface Activity versus Amorphization Activation in Cobalt Phosphate Catalysts 

      González Flores, Diego; Sánchez Villalobos, Irene; Zaharieva, Ivelina; Klingan, Katharina; Heidkamp, Jonathan; Chernev, Petko; Menezes, Prashanth W.; Driess, Matthias; Dau, Holger; Montero Villalobos, Mavis Lili (2015)
      Is water oxidation catalyzed at the surface or within the bulk volume of solid oxide materials? This question is addressed for cobalt phosphate catalysts deposited on inert electrodes, namely crystallites of pakhomovskyite ...

    • High and low affinity sites of ferrihydrite for metal ion adsorption: Data and modeling of the alkaline-earth ions Be, Mg, Ca, Sr, Ba, and Ra 

      Méndez Fernández, Juan Carlos; Hiemstra, Tjisse (2020-10-01)
      The alkaline-earth metal ion series comprises Be, Mg, Ca, Sr, Ba, and Ra. Calcium (Ca) and magnesium (Mg) are the most abundant alkaline-earth metal ions in nature and their interaction with the mineral surfaces of metal ...

    • Homopropargyl alcohol 1,1-diphenylbut-3-yn-1-ol 

      Umaña, Christian A.; Pineda Cedeño, Leslie William; Cabezas Pizarro, Jorge A. (2018)
      The asymmetric unit of the title compound, C16H14O, contains one mol­ecule with a central carbon atom having a distorted tetra­hedral geometry made of a propargylic fragment, a hy­droxy group and two aromatic rings. ...

    • Homopropargyl alcohol 5,5-diphenylpent-2-yne-1,5-diol 

      Umaña, Christian A.; Pineda Cedeño, Leslie William; Cabezas Pizarro, Jorge A. (2018)
      In the title compound, C17H16O2, the central carbon atom has a distorted tetra­hedral geometry [spread of angles = 105.71 (8)–112.75 (9)°] for its bonds to a homopropargylic but-2-yn-1-ol moiety, a hy­droxy group and two ...

    • Identification of Anziaic Acid, a Lichen Depside from Hypotrachyna sp., as a New Topoisomerase Poison Inhibitor 

      Cheng, Bokun; Cao, Shugeng; Vásquez Chaves, Víctor; Annamalai, Thirunavukkarasu; Tamayo Castillo, Giselle; Clardy, Jon; Tse-Dinh, Yuk-Ching (2013)
      Topoisomerase inhibitors are effective for antibacterial and anticancer therapy because they can lead to the accumulation of the intermediate DNA cleavage complex formed by the topoisomerase enzymes, which trigger cell ...

    • Identification of polyphenols from antiviral Chamaecrista nictitans extract using high-resolution LC–ESI–MS/MS 

      Mateos Martín, María Luisa; Fuguet, Elisabet; Jiménez Ardón, Allan Miguel; Herrero Uribe, Libia; Tamayo Castillo, Giselle; Torres, Josep Lluís (2014)
      Chamaecrista nictitans (L) extract possesses antiviral properties; it acts against the herpes simplex virus, and this may be attributed to its constituent phenolics. Here, high-resolution LC–ESI–MS/MS is used to identify ...

    • Identification of Protein Kinase C Activation as a Novel Mechanism for RGS2 Protein Upregulation through Phenotypic Screening of Natural Product Extracts 

      Raveh, Avi; Schultz, Pamela J.; Aschermann, Lauren ; Carpenter, Colleen; Tamayo Castillo, Giselle ; Cao, Shugeng; Clardy, Jon; Neubig, Richard R.; Sherman, David H.; Sjögren, Benita (2014)
      Biochemical high-throughput screening is widely used in drug discovery, using a variety of small molecule libraries. However, broader screening strategies may be more beneficial to identify novel biologic mechanisms. In ...