187,088 research outputs found
The Control of Casha (Acacia spp) on Native Pasture
No full textNative pastures, dominated by guineagrass (Panicum maximums and leucaena tLeucaena leucocephalai, provide the basic feed resource for the ruminant livestock industry in the Virgin Islands. However, many of these pastures are in advanced stages ofdeterioration because of overgrazing. There are currently no standard recommendations to prevent the continued ingress of malevolent plants such as ca~ha (Acacia spp.). A split plot field trial was set up to test the efficacy of mechanical and/or chemical treatments for the control of casha. Main plots, replicated three times, consisted of mechanical shredding vs. non-shredded mature plants. These treatments were applied in May, 1990. Subplots were 6 chemical foliar sprays: 2.0 and 3.0 kglha of dicamba alone; 1.28 and 2.56 kg/ha ofTrimecR Super Brush Killer (1:4:4 dicamba, 2,4-0 and 2,4-DP); 285 Llha of diesel oil; and a herbicide check. Subplot treatments were applied 12 wk after mechanical treatments to allow for sufficient regrowth on shredded plots. Chemical application was repeated 24 wk after the first application. Plant density of casha and frequency of canopy occurrence of all dominant plant species were taken initially in May, 1990, and again after 36 wk (just before second herbicide application) and 84 wk. Shreddin-e .i.lene prevented the 14% increase (P<0.05) in the initial ~ casha plant density (1.3 plants/m" ) that was observed on the nonshredded herbicide check, but did not kill any existing casha plant over the 84-wk period. However, shredding plus regrowth combined with dicarnba or Trimel,;R application synergistically induced greater (P <0.0 I) casha mortality (68 '7c) than similar herbicide-treated mature non-shredded plots (48% mortality). A significant leaf drop and canopy reduction (62 7~) followed the first application of diesel oil on shredded plus regrowth treatment but there was no long term topkill (4%) of existing cash a plants. The higher rates of both herbicides provided the best control of casha. Approximately 80% casha mortality was obtained by the initial application of 3.0 kg/ha of dicamba or by double application of 2.56 kg/ha of TrimecR to the shredded plus regrowth treatment without any deleterious effect on the associated leucaena or guineagrass. These data signify that mechanical shredding could be integrated with available herbicides for satisfactory control of casha on native pasture
DISEÑO DE UN CONCENTRADOR SOLAR PARA DESINFECCIÓN DE AGUA PARA CONSUMO HUMANO EN EL C.P. DE CASHA, DISTRITO SANTA MARÍA DEL VALLE, HUÁNUCO 2019
No full textEl presente estudio tiene como objetivo evaluar la efectividad del concentrador solar para desinfección del agua para consumo humano en el C.P. de Casha, Distrito Santa María del Valle, Huánuco 2019.
Siendo una investigación de tipo aplicada, experimental, longitudinal y analítica con un enfoque cuantitativo, la población está conformado por las viviendas del sector del C.P. de Casha del Distrito de Santa María del Valle haciendo un total de 15; La contrastación de la hipótesis fue mediante la prueba de t de student, apoyándonos en el SPSS V23.
Se obtuvo como resultados que los parámetros microbiológicos de las 15 muestras obtenidas antes de la intervención del concentrador solar en las cuales se observaron coliformes totales, coliformes termotolerantes y bacterias heterotróficas siendo indicadores de contaminación fecal lo cual no es apto para consumo humano ya que generan enfermedades diarreicas. Dada esta situación se decide diseñar un concentrador solar para lograr agua apta para consumo humano, siendo este fundamental para la vida del ser humano. Posteriormente aplicado el concentrador solar en el C.P de Casha; teniendo en cuenta la temperatura ambiente, termosifón y destilador solar se obtienen resultados microbiológicos negativos siendo cero.
Llegando a la conclusión que al analizar los parámetros de los coliformes totales se evidencio que existe un error típico de 1,155 con un valor significativo [t=3,464, p= 0,004], con lo que se rechaza a hipótesis nula dando lugar que el uso del concentrador solar fue efectivo para la eliminación de microorganismos logrando agua apta para consumo humano. Del mismo modo con los parámetros de los coliformes termotolerantes con error típico de 1,195 y valor significativo [t=5,464, p= 0,009], finalmente los parámetros de las bacterias heterotróficas se evidencio que existe un error típico de 1,104 con un valor significativo [t=5,196, p= 0,000]; de esa forma se estable que el concentrador solar fue efectivo para el tratamiento de la parte microbiológica del agua para consumo humano.Tesi
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
No full textWe 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
Dr. Edward P. Wimberly, ITC, July 2011
No full textThis video is a conversation with Dr. Edward P. Wimberly. Dr. Wimberly talks about his book, "No Shame in Wesley's Gospel: A Twenty-First Century Pastoral Gospel". Brad Ost, AUC Woodruff Library, is the interviewer
Author Rights and Scholarly Publishing
No full textOriginally posted at
http://blog.library.gsu.edu/2014/10/24/author-rights-and-scholarly-publishing/</p
Mapping the Discipline of the Olympic Games An Author-Cocitation Analysis
No full textThe authors conducted an author cocitation analysis on prominent authors writing about the Olympics during the 1990s. Author cocitation is an established bibliometric technique that can be used to measure the relative similarities of topics written about by the cited authors. This enables a visual representation of the “intellectual space” of the discipline, in this case the Olympics, to be created for the period under review. So core and peripheral research areas are identified, along with their major contributors. The representation appears as a two-dimensional cluster-enhanced map. Subject expertise was then applied to the results to place labels on the generated clusters of authors and their topics
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