39 research outputs found

    High selfing capability and low pollinator visitation in the hummingbird-pollinated epiphyte Pitcairnia heterophylla (Bromeliaceae) at a Costa Rican mountain forest

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    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 a través de sistemas de polinización biótica; sin embargo, la biología reproductiva de la mayoría de especies de este grupo no se ha documentado. Pitcairnia heterophylla es una bromelia epífita (raramente saxícola) que se encuentra en el sur de México, América Central y el norte de los Andes. Se estudió la polinización y el sistema de apareamiento de una población P. heterophylla en un bosque montano en Costa Rica entre enero y abril 2013. Se realizaron cuatro experimentos de polinización (agamospermia, auto-polinización espontánea, auto-polinización manual, exo-polinización manual) en 89 flores de 23 individuos (3-6 flores por individuo). Se cuantificó la producción de néctar de 18 flores en seis individuos con un refractómetro. Simultáneamente, se registraron los visitantes florales de ocho individuos en el campo con ayuda de cámaras trampa por un total de 918 horas (115 ± 52 horas por individuo, promedio ± ES). Bajo condiciones naturales la producción de semillas fue similar (540.4 ± 55.2) a la producción de las flores auto-polinizadas manualmente (516.3 ± 41.5) y las flores auto-polinizadas espontáneamente (521.1 ± 29.0), pero fue menor a las flores exo-cruzadas (670.2 ± 31.3). Las flores de P. heterophylla son auto-compatibles, con alta capacidad de polinización espontánea y sin capacidad de agamospermia. La auto-polinización intra-floral es facilitada por la ausencia de dicogamia y hercogamia floral. Las flores rojas, sin aroma, con corola tubular y con producción de néctar sugirieron polinización por ornitofilia, lo que se confirmó con el registro de 46 visitas por colibríes (Apodiformes: Trochilidae). El visitante floral más común fue Lampornis calolaemus (78 % de las visitas). A pesar de esto, la tasa de visitas durante el periodo de estudio fue baja (0.6 visitas por día por planta). La capacidad de autofecundación de P. heterophylla puede ser explicada como un mecanismo de aseguramiento reproductivo, así como para reducir el flujo de polen inter-específico de plantas taxonómicamente no relacionadas.Pitcairnioideae is the second most diverse subfamily of bromeliads (Bromeliaceae), a group exclusive to tropical regions of the New World. Pitcairnioid bromeliads have floral traits assumed to promote outcrossing through biotic pollination systems; however, the reproductive biology of most of the species of this group has not been documented. Pitcairnia heterophylla is an epiphytic (seldom saxicolous) bromeliad occurring from Southern Mexico, into the Northern Andes. We studied the pollination and breeding system of P. heterophylla in an epiphytic population at a mountain forest in Costa Rica from January to April 2013. We performed hand pollination experiments (agamospermy, autonomous self-pollination, hand self-pollination and hand cross-pollination) on 89 flowers from 23 individuals (3-6 flowers per individual) in 2013 flowering season. Nectar production was measured on 18 unvisited flowers of six individuals with a hand-held refractometer. Simultaneously, floral visitors were recorded on eight individuals with trail cameras for a total of 918 hours (115 ± 52 hours per individual, mean ± SE). Under natural conditions, seed set (540.4 ± 55.2) was similar to manually selfed flowers (516.3 ± 41.5) and autonomously selfed flowers (521.1 ± 29.0), but lower to manually outcrossed flowers (670.2 ± 31.3). The flowers of P. heterophylla are self-compatible, capable of autonomous pollination, and non-agamospermous. Intrafloral self-pollination is facilitated by adichogamy and lack of floral herkogamy. The scentless red flowers of P. heterophylla with tubular corollas and nectar production suggested ornithophilic pollination which was confirmed by video recording of 46 hummingbird visits. The most common floral visitor was the short-billed hummingbird Lampornis calolaemus which accounted for 78 % of the visits. However, the visitation rate during the flowering season was low (0.6 visits per day per plant). Selfing in P. heterophylla might be explained as a mechanism of reproductive assurance and to reduce interspecific pollen flow with taxonomically unrelated plants.Vicerrectoría de Investigación, Universidad de Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

    Current status of the peach palm (Bactris gasipaes) germoplasm bank, Guapiles, Costa Rica.

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    The objective of this study was to determine the current status of the peach palm germoplasm bank at Los Diamantes Experimental Station (BGPLD). Lost accessions were quantified and missing passport data for the remaining accessions was obtained. The passport data was obtained from the diary created by Jorge Mora Urpí, founder of the bank, in 1972. To complete the information of accessions without data, bibliographic resources were used. In 2013, a census was conducted to determine the number of surviving palm trees. Originally, the bank was composed of 7286 palms representing 837 accessions from nine countries. A total of 1471 individuals belonging to the western group and 1271 to the eastern group were identified. Currently, only 805 individuals survive (11.1%). A lower mortality was observed in the palms from the western group (62.2 ± 41.5%) compared to those in the eastern group (81.5 ± 19.6 %). The BGPLD is in a critical condition of deterioration. Urgent and concrete institutional policies are needed to rescue this important plant genetic resourceVicerrectoría de Investigación, Universidad de Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Plant diversity patterns in neotropical dry forests and their conservation implications

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    This is the author accepted manuscript. The final version is available from American Association for the Advancement of Science via the DOI in this record.Seasonally dry tropical forests are distributed across Latin America and the Caribbean and are highly threatened, with less than 10% of their original extent remaining in many countries. Using 835 inventories covering 4660 species of woody plants, we show marked floristic turnover among inventories and regions, which may be higher than in other neotropical biomes, such as savanna. Such high floristic turnover indicates that numerous conservation areas across many countries will be needed to protect the full diversity of tropical dry forests. Our results provide a scientific framework within which national decision-makers can contextualize the floristic significance of their dry forest at a regional and continental scale.This paper is the result of the Latin American and Caribbean Seasonally Dry Tropical Forest Floristic Network (DRYFLOR), which has been supported at the Royal Botanic Garden Edinburgh by a Leverhulme Trust International Network Grant (IN-074). This work was also supported by the U.K. Natural Environment Research Council grant NE/I028122/1; Colciencias Ph.D. scholarship 529; Synthesys Programme GBTAF-2824; the NSF (NSF 1118340 and 1118369); the Instituto Humboldt (IAvH)–Red colombiana de investigación y monitoreo en bosque seco; the Inter-American Institute for Global Change Research (IAI; Tropi-Dry, CRN2-021, funded by NSF GEO 0452325); Universidad Nacional de Rosario (UNR); and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). The data reported in this paper are available at www.dryflor.info. R.T.P. conceived the study. M.P., A.O.-F., K.B.-R., R.T.P., and J.W. designed the DRYFLOR database system. K.B.-R. and K.G.D. carried out most analyses. K.B.-R. R.T.P., and K.G.D. wrote the manuscript with substantial input from A.D.-S., R.L.-P., A.O.-F., D.P., C.Q., and R.R. All the authors contributed data, discussed further analyses, and commented on various versions of the manuscript. K.B.-R. thanks G. Galeano who introduced her to dry forest research. We thank J. L. Marcelo, I. Huamantupa, C. Reynel, S. Palacios, and A. Daza for help with fieldwork and data entry in Peru

    Anales del III Congreso Internacional de Vivienda y Ciudad "Debate en torno a la nueva agenda urbana"

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    Acta de congresoEl III Congreso Internacional de Vivienda y Ciudad “Debates en torno a la NUEVa Agenda Urbana”, ha sido una apuesta de alto compromiso por acercar los debates centrales y urgentes que tensionan el pleno ejercicio del derecho a la ciudad. Para ello las instituciones organizadoras (INVIHAB –Instituto de Investigación de Vivienda y Hábitat y MGyDH-Maestría en Gestión y Desarrollo Habitacional-1), hemos convidado un espacio que se concretó con potencia en un debate transdisciplinario. Convocó a intelectuales de prestigio internacional, investigadores, académicos y gestores estatales, y en una metodología de innovación articuló las voces académicas con las de las organizaciones sociales y/o barriales en el Foro de las Organizaciones Sociales que tuvo su espacio propio para dar voz a quienes están trabajando en los desafíos para garantizar los derechos a la vivienda y los bienes urbanos en nuestras ciudades del Siglo XXI

    Polinización en el género de palmas dioicas Chamaedorea (Arecaceae): comprendiendo la interacción entre anemofilia y entomofilia

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    Tesis (licenciatura en biología con énfasis en botánica)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

    Estado actual del banco de germoplasma de pejibaye (Bactris gasipaes), Guápiles, Costa Rica.

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    The objective of this study was to determine the current status of the peach palm germoplasm bank at Los Diamantes Experimental Station (BGPLD). Lost accessions were quantified and missing passport data for the remaining accessions was obtained. The passport data was obtained from the diary created by Jorge Mora Urpí, founder of the bank, in 1972. To complete the information of accessions without data, bibliographic resources were used. In 2013, a census was conducted to determine the number of surviving palm trees. Originally, the bank was composed of 7286 palms representing 837 accessions from nine countries. A total of 1471 individuals belonging to the western group and 1271 to the eastern group were identified. Currently, only 805 individuals survive (11.1%). A lower mortality was observed in the palms from the western group (62.2 ± 41.5%) compared to those in the eastern group (81.5 ± 19.6 %). The BGPLD is in a critical condition of deterioration. Urgent and concrete institutional policies are needed to rescue this important plant genetic resource.El objetivo del presente estudio fue determinar el estado actual del banco de germoplasma de pejibaye en la Estación Experimental Los Diamantes (BGPLD). Se cuantificaron las accesiones perdidas y se obtuvo la información faltante en las boletas pasaporte para las accesiones sobrevivientes. Los datos de pasaporte se obtuvieron en parte del diario elaborado por Jorge Mora Urpí, fundador del BGPLD en el año 1972. Para aquellas accesiones sin datos se utilizaron fuentes bibliográficas para complementar la información. Se realizó un censo en el año 2013 para determinar la cantidad de palmeras en pie. El banco estaba originalmente compuesto por 7286 palmeras representando 837 accesiones de nueve países. Se identificaron 1471 individuos pertenecientes al grupo occidental y 1271 al grupo oriental. Actualmente solo sobreviven 805 individuos (11,1%). Se observó una menor mortalidad en las palmeras del grupo occidental (62,2 ± 41,5%) que en el grupo oriental (81,5 ± 19,6%). El BGPLD se encuentra en un estado crítico de deterioro. Se deben llevar a cabo políticas concretas y urgentes para rescatar este importante recurso fitogenético

    Libro para entender las estrategias del fútbol

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    Han pasado algunas semanas desde que la copa del mundo de futbol término, sin embargo, este deporte siempre está presente en nuestras vidas, y mucho más en los reales fanáticos del deporte. Si usted es uno de esos fanáticos, debe conocer el libro de los docentes Oscar Milton Rivas Borbón y Erick Sánchez Alvarado: Táctica del fútbol: teoría y entrenamiento. Una de las novedades editoriales que la Editorial de la Universidad del Rosario trae al mundo académico porque desde este deporte también se muestran lógicas, estrategias, y enseñanzas que están en la actividad física

    Neither insects nor wind: ambophily in dioecious Chamaedorea palms (Arecaceae)

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    Pollination of Neotropical dioecious trees is commonly related to generalist insects. Similar data for non‐tree species with separated genders are inconclusive. Recent studies on pollination of dioecious Chamaedorea palms (Arecaceae) suggest that species are either insect‐ or wind‐pollinated. However, the wide variety of inflorescence and floral attributes within the genus suggests mixed pollination mode involving entomophily and anemophily. To evaluate this hypothesis, we studied the pollination of Chamaedorea costaricana, C. macrospadix, C. pinnatifrons and C. tepejilote in two montane forests in Costa Rica. A complementary morphological analysis of floral traits was carried out to distinguish species groups within the genus according to their most probable pollination mechanism. We conducted pollinator exclusion experiments, field observations on visitors to pistillate and staminate inflorescences, and trapped airborne pollen. A cluster analysis using 18 floral traits selected for their association with wind and insect pollination syndromes was carried out using 52 Chamaedorea species. Exclusion experiments showed that both wind and insects, mostly thrips (Thysanoptera), pollinated the studied species. Thrips used staminate inflorescences as brood sites and pollinated pistillate flowers by deception. Insects caught on pistillate inflorescences transported pollen, while traps proved that pollen is wind‐borne. Our empirical findings clearly suggest that pollination of dioecious Chamaedorea palms is likely to involve both insects and wind. A cluster analysis showed that the majority of studied species have a combination of floral traits that allow for both pollination modes. Our pollination experiments and morphological analysis both suggest that while some species may be completely entomophilous or anemophilous, ambophily might be a common condition within Chamaedorea. Our results propose a higher diversity of pollination mechanisms of Neotropical dioecious species than previously suggested.Vicerrectoría de Investigación, Universidad de Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí
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