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DIFERENCIACION FENOTIPICA EN POBLACIONES DE ANODA CRISTATA CON DIFERENTE GRADO DE MANEJO
No full textEstructura comunitaria de microcosmos en un ecosistema semiárido intertropical en México
Get PDFThis thesis evaluates the community structure of protégé organisms within the Prosopis laevigata’s microcosm in the Zapotitlan valley, Puebla, Mexico in “Helia Bravo Hollis” Botanical Garden. The study of community structure required a meta-community approach that considered temporal and spatial factors. Using methodologies derived from multivariate analysis, assembly patterns of plant communities within 70 microcosms are described, and a general description of arthropods associated with microcosms is given. First, a floristic checklist of protégé species under the nurse plant P. laevigata is presented, and the influence of mesquite size (i.e., canopy cover and height) on the richness and diversity of plant species were analyzed. This work contributes to the registration of 48 protégé plant species that had not been previously reported beneath P. laevigata. In addition, it was observed that diversity of plant communities in microcosms was greater during the rainy season compared to the dry season, whereas the size of mesquite had a positive influence on richness, diversity, and abundance of protégé plants. Secondly, results to discontinuous functional diversity of protégé species at the study site are shown. Functional groups were considered as a parameter of functional diversity, that is, functional richness. Grouping of protégé species was complemented with analyzes that evaluated the separation between groups. Thus, a high measure of functional richness was detected, which does not change throughout seasonality, and it is inferred that there may be compensation between functionally equivalent species. Likewise, dispersal syndromes apparently are an important functional trait at the meta-community level, because species small propagules can be dispersed by wind in the dry season and by water during the rainy season. The third instance showed that intraspecific phenotypic nurse variation in a continuous gradient instead of architecture types is relevant for the analysis of protégé plants metacommunity structure. The results suggest that the patterns of similarity in the composition of species vary throughout seasonally, whereas deterministic and stochastic processes probably occur simultaneously, because protégé species turnover is related both to their geographic location and to the microenvironmental characteristics. Finally, a general patterns of terrestrial arthropods communities are descripted. Six arthropod trophic guilds were found, and an intermediate richness of families was found, in which Formicidae stands out for its larger number of morphospecies. No close relationships between trophic guilds and environmental factors were detected. Keywords: diversity, facilitation, microcosm, microenvironment, nurse plant, seasonality, semiarid ecosystem.En la presente tesis se abordó el análisis de la estructura comunitaria de organismos protegidos dentro de microcosmos formados por Prosopis laevigata en el valle de Zapotitlán, Puebla, México, dentro del área de conservación del Jardín Botánico “Helia Bravo Hollis”. El estudio de la estructura de comunidades requirió una aproximación desde un enfoque metacomunitario que consideró factores temporales y espaciales. Mediante el uso de metodologías derivadas de análisis multivariados, se describen los patrones de ensamble de comunidades vegetales dentro de 70 microcosmos y se da una descripción general de las comunidades de artrópodos asociadas a diez microcosmos. Primero se presenta un listado florístico de las especies protegidas bajo la cobertura de la planta nodriza P. laevigata y se analiza la influencia de la talla de los mezquites (i.e., cobertura y la altura) sobre la riqueza y diversidad de especies vegetales. Se contribuye con el registro de 48 especies vegetales protegidas que no habían sido reportadas anteriormente bajo la cobertura de mezquites. Además, se observó que la diversidad de las comunidades de plantas en los microcosmos fue mayor durante la temporada de lluvias respecto a secas y que el tamaño de los mezquites tiene una influencia positiva sobre la riqueza, diversidad y abundancia de plantas protegidas. Segundo, se muestran los resultados de un primer acercamiento a la diversidad funcional discontinua de especies protegidas en el sitio de estudio. Como parámetro de la diversidad funcional se consideró a los grupos funcionales, es decir, la riqueza funcional. El agrupamiento de las especies protegidas fue complementado con análisis que evaluaron la separación entre grupos. Así, se encontró que existe una medida alta de riqueza funcional, que no cambia entre estaciones, y se infiere que puede haber compensación entre especies funcionalmente equivalentes. Asimismo, o, los síndromes de dispersión parecen ser un rasgo importante a nivel metacomunitario, ya que las especies con propágulos pequeños pueden ser dispersadas por el viento en época seca y por agua durante las lluvias. Tercero, se estimó que la variación fenotípica intraespecífica de las nodrizas es relevante para el análisis de la estructura metacomunitaria de la vegetación protegida en un gradiente continuo y no en tipos de arquitectura. Los resultados sugieren que los patrones de similitud en la composición de especies varían estacionalmente y que probablemente se estarían produciendo simultáneamente procesos determinísticos y estocásticos, ya que el recambio de especies entre microcosmos está relacionado tanto con su ubicación geográfica, como con las características microambientales en ambas estaciones. Finalmente, se hace una descripción general de los artrópodos terrestres dentro del sistema de microcosmos. Se encontraron seis gremios tróficos de artrópodos y se halló una riqueza de familias intermedia con respecto a estudios previos, en la que Formicidae sobresale por su mayor cantidad de morfoespecies. No se detectaron relaciones estrechas entre los gremios tróficos y los factores ambientales, por lo que sería necesario ampliar el muestreo de la artropofauna y realizar nuevos análisis para descubrir patrones más claros y concluyentes. Palabras clave: diversidad, estacionalidad, facilitación, microcosmos, microambiente, planta nodriza, ambiente semiárido
Diferenciación fenotípica en poblaciones de Anoda cristata con diferente grado de manejo
Get PDFAnoda cristata es una Malvácea de amplia distribución en México, utilizada como recurso alimenticio en la zona centro del país, siendo las hojas anchas, suaves y poco pubescentes el rasgo de interés. En la región de la Montaña de Guerrero (Copanatoyac y Tlapa) se encuentran poblaciones ruderales de A. cristata creciendo a orillas de los caminos y como elemento de la vegetación perturbada. También hay poblaciones sometidas a distintos tipos de manejo, que incluyen a las arvenses toleradas en los campos de cultivo y arvenses fomentadas, promoviendo su establecimiento y crecimiento en las milpas y huertos. En este estudio se aplicaron encuestas a 71 personas para documentar los usos y el manejo de las poblaciones. Para evaluar si la selección humana ha modificado algunos rasgos fenotípicos, particularmente aquellos de interés, se diseñó un experimento de jardín común, en donde se midieron diferentes atributos vegetativos y reproductivos de individuos provenientes de los tres tipos de manejo. También se realizó un análisis de componentes nutricionales en las mismas poblaciones. Los resultados de las encuestas confirmaron que es un recurso ampliamente usado y apreciado en la región durante todo el año y que la gente diferencia claramente características morfológicas que tienen que ver con el uso. El experimento reveló una fuerte diferenciación entre las poblaciones, asociada con las preferencias de consumo y el tipo de manejo, resaltando ciertos atributos de las hojas, como pubescencia y área foliar, así como aquellos rasgos correlacionados que forman parte de la historia de vida de la especie (fenología y reproducción) y que no se encuentran bajo selección consciente. Se encontraron diferencias significativas en los componentes nutricionales entre arvenses y ruderales, donde los elementos con mayor aporte nutricional se encontraron en la población Fomentada, mientras que los elementos de estructura y soporte físico están en la Ruderal. Los mecanismos de defensa también mostraron variación fenotípica relacionada con el tipo de manejo. Así la población Ruderal muestra tendencias hacia la resistencia, mientras que en la población Tolerada es hacia la tolerancia. A diferencia de lo que se esperaba no se encontró nada claro en la población Fomentada. Tal como se esperaba, la variación en las características fenotípicas mostradas por las poblaciones es resultado de la intensidad de manejo a las que fueron y están siendo sometidas, confirmando que esta especie se encuentra en un proceso de domesticación en la región de estudio.Anoda cristata is a Malvaceae of wide distribution in Mexico, which tender and glabrous leaves are considered important for food consumption in the central region of this country. In the Mountain of Guerrero region (municipalities of Copanatoyac and Tlapa), ruderal populations of A. cristata are growing roadsides, and as a frequent element of secondary vegetation. Also, populations with different types of management are found elsewhere, which correspond to agrestal category with two types of management: tolerated growing in crop fields, and fomented populations, which are growing in “milpas”, and orchards. In the present study 71 interviews were applied to local people, in order to document the uses, as well as the different types of management that people have developed to the populations. To evaluate if human selection has modified some phenotypic attributes, in particular those related with local uses and are important to people, different vegetative and reproductive attributes were measured in individuals corresponding to the three types of management growing in a common garden experiment. Also, nutritional composition was evaluated in the same populations. Interviews confirmed that this plant resource is widely used and appreciated in this region throughout the year, and people recognize morphological differences associated with use. Results of the experiment exhibited a strong differentiation between populations, related with use and type of management. Those attributes related with leaves, pubescence and foliar area, as well as some correlated attributes of life history (phenology and reproduction), which are not the target of human selection, exhibited statistical differences. Differences between ruderal and agrestal populations where also detected in the nutritional compounds, where higher nutritional composition was recorded in the fomented population, and structural and physical support elements were higher in ruderal population. Phenotypic variation in mechanisms of defense exhibited statistical differences related with type of management. Ruderal population exhibited higher levels of resistance, while agrestal tolerated exhibited higher levels of tolerance. In contrast with theory, agrestal fomented population didn´t exhibited either of both responses. As expected, variation in phenotypic attributes among populations is the result of the variation in the intensity of management in the past and present. These results confirm that A. cristata is under a domestication process in the area of study
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
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
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