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Dinámica poblacional de Dactylopius opuntiae (Cockerell) y sus enemigos naturales en Tlalnepantla, Morelos
No full textLas ―cochinillas del nopal‖ (Hemiptera: Dactylopiidae), son plagas primarias en los cultivo de nopal verdura
(Opuntia ficus-indica) en la parte central de México y no hay un método satisfactorio para su manejo. Los
estudios sobre su identidad taxonómica y sus enemigos naturales son escasos yno existen trabajos sobre su
dinámica poblacional y factores de regulación. En el presente trabajo se planteó conocer las especies
presentes de Dactylopius y sus enemigos naturales, además de conocer sus dinámicas poblacionales y el
efecto de los enemigos naturales y factores climáticos en una de las áreas de mayor producción de nopal
verdura en México (Tlalnepantla, Morelos). Se seleccionaron 30 sitios distribuidos en esta región para
conocer las especies de cochinilla presentes. Además, se establecieron cinco sitios de muestreo
sistemático,cada dos semanas,de enemigos naturales durante un periodo anual (febrero 2008 a 2009). Se
consideraron los factores abióticos: temperatura (máxima y mínima) y precipitación para el análisis de
correlación con la presencia de la cochinilla y sus enemigos naturales. Ejemplares de la cochinilla y sus
enemigos se enviaron a expertos de cada grupo para su determinación. La cochinilla Dactylopius opuntiae fue
la única especie en la región y se observó durante todo el periodo de muestreo, sus poblaciones se
incrementaron en febrero y alcanzaron su mayor infestación entre marzo y mayo, posteriormente
disminuyeron hasta alcanzar su nivel más bajo en enero. Los enemigos naturales en orden de abundancia (%)
fueron: Leucopis bellula (44.74), Sympherobius barberi (25.12), Laetilia coccidivora (17.89), Hyperaspis
trifurcata (12.25), Salpingogaster cochenillivorus (0.18), Sympherobius angustus (0.03) y Chilocorus cacti
(0.03), de los cuales L. bellula y S. barberi sobresalieron por su abundancia . La temperatura máxima fue un
factor que se correlacionó positivamente con el incremento de D. opuntiae, la lluvia en conjunto con otros
factores, inherentes al manejo heterogéneo de los cultivos, fueron elementos relevantes en las fluctuaciones
poblacionales de la cochinilla y sus enemigos naturales._____In Central Mexico cochineals (Hemiptera: Dactylopiidae) are primary pest of ―nopalitos‖, which are
immature edible cactus pads (Opuntia ficus-indica), and there is not an important tool for its management. On
the other hand, taxonomic identity, natural enemies and populations dymamics about this pest are rare in
many places in Mexico, including those where the crop has an economic impact on the population such as
Tlalnepantla, Morelos. The objective of this work was to identify Dactylopius species, its natural enemies and
population dynamics at Tlalnepantla. We also wanted to correlate some climatic factors on the insect
population. We selected 30 sites all along that region to collect an to identify Dactylopius species. In order to
monitor its natural enemies we visited and collected them systematically at five places, every other week,
from February 2008 to February 2009. Specimens of pest and natural enemies were sent to identify with
specialists of each group. We collected data on temperature and precipitation and we did some correlations on
abiotic factors and insect population dynamics. Dactylopius opuntiae was the only species recovered. It was
present any time of the year, but it began to increase on February, it reached its highest populations between
March and May, and it declined on January. Following abundanceDactylopius predators (%), we found
Leucopis bellula (44.74), Sympherobius barberi (25.12), Laetilia coccidivora (17.89), Hyperaspis trifurcata
(12.25), Salpingogaster cochenillivorus (0.18), Sympherobius angustus (0.03) y Chilocorus cacti (0.03). L.
bellula y S. barberi were the most abundant any time the year. High temperatures correlated with high
populations of D. opuntiae, but rain and management practices, such as pesticides used and pruning, were
important to affect the pest and natural enemies populations.Tesis ( Maestría en Ciencias, especialista en Entomología y Acarología).- Colegio de Postgraduados, 2009.CONACY
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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