• Clustering binary data by application of combinatorial optimization heuristics 

  Trejos Zelaya, Javier; Amaya Briceño, Luis Eduardo; Jiménez Romero, Alejandra; Murillo Fernández, Alex; Piza Volio, Eduardo; Villalobos Arias, Mario Alberto (2019-08-09)

  We study clustering methods for binary data, first defining aggregation criteria that measure the compactness of clusters. Five new and original methods are introduced, using neighborhoods and population behavior combinatorial ...

• The primary freshwater crabs of Guatemala (Decapoda: Brachyura: Pseudothelphusidae), with comments on their conservation status 

  Wehrtmann, Ingo S.; Magalhães, Célio; Orozco, Mónica N. (2016)

  The freshwater crabs of the family Pseudothelphusidae Ortmann, 1893 are restricted to the Neotropics and many species have an elevated risk of extinction. The majority of pseudothelphusids is considered to be data-deficient, ...

• Freshwater crabs as predators and prey: the case of Ptychophallus uncinatus Campos & Lemaitre, 1999 (Brachyura, Pseudothelphusidae) from Costa Rica, Central America 

  Wehrtmann, Ingo S.; Hernández Díaz, Dayan; Cumberlidge, Neil (2019)

  Primary freshwater crabs are an important component of the food web in aquatic ecosystems, but our knowledge about the role of these decapods as predators and as prey is far from complete. Here we report observations of ...

• Effects of temperature on the embryonic development and hatchling size of Betaeus emarginatus (Decapoda: Caridea: Alpheidae) 

  Wehrtmann, Ingo S.; López, Gastón A. (2003)

  Betaeus emarginatus is an alpheid shrimp inhabiting rock pool environments characterized by strong fluctuations of ambient factors. Here we describe the embryonic development of B. emarginatus, and analyse the effects of ...

• Grado de vulnerabilidad ante la presencia del cocodrilo americano (Crocodylus acutus) en cinco comunidades costeras de la Región Pacifico Central de Costa Rica, 2017 - 2018 

  Durán Apuy, Alejandro Alberto (2020-09)

  El conflicto entre seres humanos y animales silvestres es un fenómeno recurrente a nivel mundial y que se origina desde que ambos comparten los mismos hábitats y recursos. Entre el 2017 y el 2018, se evaluó el grado de ...

• Neotropical freshwater crabs (Decapoda: Pseudothelphusidae) shred leaves 

  Yang, Carol; Wehrtmann, Ingo S.; Wenger, Seth J.; Rugenski, Amanda T. (2020)

  Freshwater crabs are macroconsumers that are commonly found in Neotropical headwater streams that may play a key role in energy flow and nutrient cycling in detrital food webs. Although studies have examined the feeding ...

• Estimation of the yield curve for Costa Rica using combinatorial optimization metaheuristics applied to nonlinear regression 

  Quirós Granados, Andrés; Trejos Zelaya, Javier (2020-09-20)

  The term structure of interest rates or yield curve is a function relating the interest rate with its own term. Nonlinear regression models of Nelson-Siegel and Svensson were used to estimate the yield curve using a sample ...

• Crustacean fauna (Stomatopoda: Decapoda) associated with the deepwater fishery of Heterocarpus vicarius (Decapoda: Pandalidae) along the Pacific coast of Costa Rica 

  Wehrtmann, Ingo S.; Echeverría Sáenz, Silvia (2007)

  Commercial bottom trawling is a successful and commonly used method to catch marine shrimps. However, the shrimp fishing gears are poorly selective, and in addition to the target species they catch and retain large quantities ...

• Air-exposure behavior: a restricted or a common conduct among intertidal hermit crabs? 

  Perez Miguel, Marta; Wehrtmann, Ingo S.; Drake, Pilar; Cuesta, José (2020)

  A new behavior related to shell care was recently reported for the intertidal hermit crab Clibanarius erythropus (Latreille, 1818) in the Gulf of Cádiz (southwestern Europe). It also has been observed in other species of ...

• Distribution and reproduction of Ambidexter panamense and Palaemonetes schmitti in Pacific Costa Rica (Crustacea, Decapoda) 

  Wehrtmann, Ingo S. (1990)

  Este constituye el primer registro de las especies de carídeos P. schmitti y A. panamense para Costa Rica. Adultos de ambas especies fueron colectados en el estero de Punta Morales, Golfo de Nicoya, de enero a diciembre ...

• Salinity effect on embryonic development and survival of the first zoeal stage of Macrobrachium tenellum (Smith, 1871) (Crustacea, Palaemonidae) 

  Vargas Ceballos, Manuel A.; Vega Villasante, Fernando; García Guerreo, Marcelo U.; Chong Carrillo, Olimpia; Badillo Zapata, Daniel; López Uriarte, Ernesto; Wehrtmann, Ingo S. (2018)

  The objective of this work is to provide information to understand the effect of different salinities on the survival of embryos and newly-hatched larvae of Macrobrachium tenellum. The survival of M. tenellum embryos was ...

• Description of a new species of Pagurus Fabricius, 1775 (Crustacea: Paguroidea: Paguridae) from the Pacific coast of Costa Rica, Central America, with notes on Pagurus albus (Benedict, 1892) 

  Ayón Parente, Manuel; Wehrtmann, Ingo S. (2019)

  A redescription of Pagurus albus (Benedict, 1892) is presented together with a description of a new species of hermit crab, Pagurus pseudoalbus sp. n., from the Pacific coast of Costa Rica. Pagurus pseudoalbus sp. n. differs ...

• Análisis de la metilación del ADN en las especies forestales Sideroxylon capiri e Hyeronima alchorneoides y su posible relación con los factores climatológicos de la región del pacífico en Costa Rica 

  Muñoz Flores, Carolina (2020-07-02)

  Las investigaciones sobre la metilación del ADN en plantas se han enfocado, hasta el momento, en cultivos anuales de gran importancia económica o en especies modelo cultivadas, en su mayoría, bajo condiciones artificiales ...

• Caracterización de diversidad genética en poblaciones cultivadas de Cas (Psidium friedrichsthalianum (O. Berg) Nied) utilizando descriptores citogenéticos y moleculares para fines de mejoramiento genético 

  Rojas Gómez, Mónica María (2020-07)

  Psidium friedrichsthalianum (O. Berg) Nied es una especie cultivable de origen tropical de la familia Myrtaceae, subfamilia Myrtoideae, tribu Myrteae (Lucas et al. 2019).Actualmente, no hay información sobre la cantidad ...

• Síntesis y evaluación de complejos de cobre (I/II) con ligandos polipiridínicos como mediadores redox en celdas solares sensibilizadas con tintes 

  Ledezma Gairaud, Marisol; Pineda Cedeño, Leslie William; Solera Rojas, José Andrés (2020)

  En las celdas solares sensibilizadas con tintes (DSSCs), el mediador redox en el electrolito permite la transferencia de cargas al regenerar las moléculas del tinte durante su operación. Se sintetizaron y caracterizaron ...

• Tetra­aqua­bis­(2,3-di­hydro-1,4-benzodioxine-2-carboxyl­ato)calcium(II) 

  Camargo Cortés, Esmit B.; Acosta, Mirna; Martínez, Juan C.; Pineda Cedeño, Leslie William (2020)

  The acid–base reaction of 1,4-benzodioxane 2-carb­oxy­lic acid with calcium carbonate furnished the centrosymmetric title compound, [Ca(C9H7O4)2(H2O)4], in which the metal ion is octa­hedrally coordinated by two monodentate ...

• Bis(μ2-benzoato-κ2O,O′)bis­(benzoato-κO)bis(ethanol-κO)bis­(μ3-hydroxido)hexa­kis­(μ-pyrazol­ato-κ2N,N′)hexa­copper(II) ethanol disolvate 

  Ledezma Gairaud, Marisol; Pineda Cedeño, Leslie William (2019)

  Trinuclear copper–pyrazolate entities are present in various Cu-based enzymes and nanojar supra­molecular arrangements. The reaction of copper(II) chloride with pyrazole (pzH) and sodium benzoate (benzNa) assisted by ...

• 1,3-Bis{[(2,6-di­methyl­phen­yl)sulfan­yl]meth­yl}benzene 

  Garita Salazar, Bruno; Pineda Cedeño, Leslie William (2019)

  The structure of the title compound, C24H26S2, an example of a pincer ligand with an SCS-chelation motif, illustrates the steric effects of the methyl groups in the thio­phenyl rings at the 2- and 6-positions, forcing a ...

• Revisión sistemática del género Myoxanthus (Orchidaceae: Pleurothallidinae) en Costa Rica 

  Rojas Alvarado, Gustavo (2020)

  The ten Costa Rican species of Myoxanthus are discussed, described and illustrated based mainly on native living material. a key for the species, notes on history, ecology, diagnostic features, taxonomy and distribution ...

• Crystal structures and biological activity of 1,1,4-tri­phenyl-substituted 1,3-enyne com­pounds 

  Pineda Cedeño, Leslie William; Arias Echandi, María Laura; Cabezas Pizarro, Jorge A. (2019)

  1,3-Enyne structural motifs are versatile building blocks in organic synthesis and occur widely in various natural products with many of them being highly active as cytotoxic macrolides and antitumour antibiotics. This ...

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