1,720,968 research outputs found
Impacto de las gramíneas invasoras en el medio ambiente, biodiversidad y los cultivos en Irán
No full text[EN] The high number of alien grasses in Iran makes it necessary to prioritize species for mitigating their negative consequences on the environment and agricultural production. We classified 34 alien grasses in Iran based on the IUCN Environmental Impact Classification of Alien Taxa (EICAT-IUCN) to assess their risks on native species and mapped their distributions in Iran’s ecological zones. We also discussed their impacts on agriculture and management options. Rottboellia cochinchinensis, Paspalum distichum and Microstegium vimineum have the potential to cause massive impacts, while Cenchrus longispinus, Eragrostis curvula, Panicum repens, Paspalum urvillei, Cortaderia jubata and Phyllostachys reticulatacan cause major impacts on native species. Competition, transmission of disease and ecosystem structural impact accounted for over 49% of the mechanisms leading to environmental impacts. The Fisher's exact test indicates a significant association between the EICAT-IUCN score and life cycle. Of the 23 grasses invading crops, 60% have infested rice fields; and P. repens, P. distichum, Paspalum dilatatum and Leptochloa chinensis have the highest potential impact on yield losses (>60% in some cases in worldwide). P. distichum and P. repens can have the greatest potential impacts on both the environment and agriculture. Conservation priorities must be established to address the potential environmental impacts caused by alien grass species in Iran.[ES] El elevado número de gramíneas invasoras en Irán hace necesario priorizar las especies para mitigar sus consecuencias negativas sobre el medio ambiente y la producción agrícola. Clasificamos 34 gramíneas invasoras en Irán basándonos en la Clasificación de Impacto Ambiental de Taxones Exóticos (EICAT-IUCN) de la UICN para evaluar sus riesgos sobre las especies autóctonas y cartografiamos su distribución en las zonas ecológicas de Irán. También analizamos sus repercusiones en la agricultura y las opciones de gestión. Rottboellia cochinchinensis,Paspalum distichum y Microstegium vimineum pueden causar importantes repercusiones, mientras que Cenchrus longispinus, Eragrostis curvula, Panicum repens,Paspalum urvillei, Cortaderia jubata y Phyllostachys reticulata pueden causar repercusiones importantes en las especies autóctonas. La competencia, la transmisión de enfermedades y el impacto en la estructura de los ecosistemas representaron más del 49 % de los mecanismos que provocan impactos ambientales. La prueba exacta de Fisher indicó una asociación significativa entre la puntuación EICAT-UICN y el ciclo de vida. De las 23 gramíneas que invaden los cultivos, el 60 % ha infestado los arrozales; yP. repens, P. distichum, Paspalum dilatatum y Leptochloa chinensis tienen el mayor impacto potencial en las pérdidas de rendimiento (>60 % en algunos casos). P. distichum y P. repens pueden tener los mayores impactos potenciales tanto en el medio ambiente como en la agricultura. Es necesario establecer prioridades de conservación para abordar los posibles impactos ambientales causados por las especies de gramíneas invasoras en Irán.Gorgan University of Agricultural Sciences and Natural Resources (GUASNR), Iran supported this research (project no. GAU-03-508-20).Peer reviewe
Factors Influencing the Variation of Plants' Cardinal Temperature: A Case Study in Iran. In: Ecology and Management of Invasive Plants
No full textThe book is a reprint of articles from the Special Issue published online in the open access journal Plants
(ISSN 2223-7747) (available at: www.mdpi.com/journal/plants/special issues/FVE66LN620).Plants 13(20): 2848 (2024) https://doi.org/10.3390/plants13202848The establishment and spread of plants in their native or alien geographical ranges are determined by their germination. This study investigated the impact of different factors on variations in cardinal temperatures. We used the lm procedure and measured the effect size by the Eta-square approach to find the association of different factors (species, ecotypes, origin (native/alien), year, and life cycle) with the cardinal temperatures of 31 species. Our results showed that the base, optimum, and maximum temperatures responded differently to these factors. The base temperature was less impacted by ecotypes compared with the optimum and maximum temperatures, whereas the species had a higher impact on the variation in the base temperature. The effect of the origin of weedy plants on the base temperature was higher than the optimum and maximum temperatures. The effect of the year on the optimum temperature was more prominent than that on the base and maximum temperatures. The results confirmed that weedy alien plants preferred high and narrow ranges of base, optimum, and maximum temperatures and probably will be more problematic in summer crops. The results indicate that alien plants can benefit from warmer conditions in invaded areas at the germination stage. These findings lay the foundation for further studies to elucidate which factors are more important.This work was funded by the Gorgan University of Agricultural Sciences and Natural Resources (GUASNR), Iran (project no. 02-490-49).Peer reviewe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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