1,720,959 research outputs found
Micología en Bolivia: Un tema Latente
Get PDFEl reino de los hongos es uno de los más diversos grupos de organismos en el planeta, están ampliamente distribuidos en la naturaleza, principalmenteen ambientes terrestres y en menor proporción en ambientes acuáticos. Muchos científicos sugieren que el Reino de los Hongos seria hiperdiverso ypodría superar los 3.5 M de especies (O’Brien et al. 2005). Muchas especies aun no fueron descritas y podrían estar presentes en ecosistemas tropicales,en ambientes no explorados, aunque también existirían especies cripticas. Bolivia es considerada como uno de los países megadiversos a nivel mundialen riqueza animal, vegetal, insectos y microorganismos, en su amplio territorio contiene diversos ecosistemas que ofrecen una amplia variedad dehábitats de esta riqueza
Recursos genéticos de hongos
Get PDFSr. Editor.El reino de los hongos (Fungi) es uno de los grupos de mayor diversidad en el planetatierra, estimaciones sugieren que la diversidad de este grupo es hiperdiverso. Estimaciones como 1.5 M de especies (Hawksworth 1991) que fueron aceptadas y que actualmente con las técnicas de moleculares este valor fue subestimado. Últimas estimacionessugieren que existiera entre 3.5 a 5.1 M de especies (O’Brien et al. 2005), sin embargoalgunos autores mencionan que podría existir 9.9 M de especies de hongos (Cannon1997). Hasta la fecha aproximadamente se han descrito 100000 especies (Kirk et al. 2008) que equivaldría a 2.8% (en base a 3.5) descubiertos a nivel mundial
Recursos genéticos de hongos
Get PDFSr. Editor.El reino de los hongos (Fungi) es uno de los grupos de mayor diversidad en el planetatierra, estimaciones sugieren que la diversidad de este grupo es hiperdiverso. Estimaciones como 1.5 M de especies (Hawksworth 1991) que fueron aceptadas y que actualmente con las técnicas de moleculares este valor fue subestimado. Últimas estimacionessugieren que existiera entre 3.5 a 5.1 M de especies (O’Brien et al. 2005), sin embargoalgunos autores mencionan que podría existir 9.9 M de especies de hongos (Cannon1997). Hasta la fecha aproximadamente se han descrito 100000 especies (Kirk et al. 2008) que equivaldría a 2.8% (en base a 3.5) descubiertos a nivel mundial
Sistemas de producción biointensiva y tradicional sobre parámetros agronómicos de hortalizas
No full textResumen El altiplano de Bolivia afronta sequias, heladas frecuentes debido al cambio climático, que afecta los rendimientos y la productividad de las hortalizas, Pro Rural conjuntamente con la Universidad Técnica de Oruro, ha desarrollado e implementado Unidades Familiares Agroecológicas Biointensivas (UFABs) como una alternativa a la producción agrícola familiar en el altiplano, caracterizado por el uso eficiente del agua, mejorando las propiedades del suelo mediante la fertilización localizada y la sustitución de agro-químicos por insumos agroecológicos. El objetivo de esta investigación fue determinar dos sistemas producción agrícola sobre parámetros agronómicos de seis hortalizas. Se estableció un área experimental en arreglo factorial dispuestas en un diseño bloques completos al azar con seis tratamientos (especies de hortalizas) y dos sistemas de producción (bio intensivo y sistema tradicional), riego por goteo sistema biointensivo e inundación en el sistema tradicional. Según los resultados obtenidos sobre parámetros agronómicos se aprecia que existe diferencia estadística en rendimiento y variables agronómicas (peso planta, longitud raíz, y altura planta) apreciándose una superioridad en el sistema biointensivo, similares resultados se aprecia en las hortalizas de hoja, el volumen de agua consumido se aprecia que existe mayor eficiencia en el uso del sistema de riego por goteo con un 90 %, la cantidad de microorganismos del suelo es más de un 50 % es sistema biointensivo, resultados similares se aprecia en los análisis químicos del suelo.Abstract The Altiplano of Bolivia faces droughts and frequent frosts due to climate change, which affect yields and productivity of vegetables. Pro Rural, together with the Technical University of Oruro, has developed and implemented Biointensive Agroecological Family Units (UFABs) as an alternative to family agricultural production in the Altiplano, characterized by the efficient use of water, improving soil properties through localized fertilization and the substitution of agrochemicals for agro ecological inputs. The objective of this research was to determine two agricultural production systems on agronomic parameters of six vegetables. An experimental area was established in a factorial arrangement arranged in a randomized complete block design with six treatments (vegetable species) and two production systems (biointensive and traditional system), drip irrigation in the biointensive system and flooding in the traditional system. According to the results obtained on agronomic parameters, there is a statistical difference in yield and agronomic variables (plant weight, root length, and plant height) showing a superiority in the biointensive system, similar results are seen in leafy vegetables, the volume of water consumed shows that there is greater efficiency in the use of drip irrigation system with 90%, the amount of soil microorganisms is more than 50% in the biointensive system, similar results are seen in the chemical analysis of the soil
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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