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Genotypic differences in vase life of Anthurium andraeanum (Hort.) cut-flowers are associated with differences in spathe chlorophyll content
No full textAnthurium (Anthurium andraeanum (Hort.)) is an important crop in the worldwide cut-flower industry, valued in particular for its showy colors and long vase life, which varies from a few days to several weeks depending on the cultivar. Previous work suggested that long vase life is associated with the chlorophyll content of the spathe, especially when more light is available. Here we compare the vase life of ten anthurium cultivars covering a range of chlorophyll contents, using two light intensities: low light (40 µmol m −2 s −1) and high light (400 µmol m −2 s −1). The experiment was arranged in a factorial design with six replicate cut-flowers per cultivar per light intensity, and measurements were recorded weekly for cut-flower degradation, water uptake, spathe chlorophyll content and spathe hyperspectral reflectance. Cultivar differences in vase life were positively associated with differences in the initial spathe chlorophyll content (accounting for > 60 % of the variation). The use of high light also significantly increased vase life in three of the high chlorophyll cultivars. Chlorophyll content increased over time in some cultivars, and this increase was associated with extended vase life under high light (accounting for 69 % of the variation). In both cases chlorophyll content provided a better indicator of vase life than the red dip index (R800 nm – R685 nm) derived from hyperspectral reflectance. The results show that cultivars with a high initial chlorophyll content often have an ability to ‘re-green’ by increasing chlorophyll content while in the vase. Both high initial chlorophyll content and the ability to perform re-greening are associated with a longer vase life suggesting that chlorophyll activity in the spathe helps to maintain the cut-flowers. </p
The impact of light on vase life in (Anthurium andraeanum Hort.) cut flowers
No full textThe impact of light quality and quantity on vase life was investigated using Anthurium (Anthurium andraeanum Hort.). Cultivars ‘Spirit’ and ‘Honduras’, were chosen based on their contrasting vase life in previous studies, and designated as ‘Vshort’ and ‘Vlong’ respectively. Both cultivars were kept under three light regimes at 12 h day length: fluorescent lights of 40 μmol m-2 s-1, low intensity LEDs producing light at 40 μmol m-2 s-1 and high intensity LEDs producing light at 400 μmol m-2 s-1. Degradation, water uptake and hyperspectral reflectance were measured three times a week as the cut flowers degraded. Spadix necrosis was used to quantify cut flower degradation over time and to determine the vase life for each cultivar. Light regime had a significant impact on vase life and water uptake in Vlong but not in Vshort, with high intensity LEDs resulting in a marked increase in the vase life of Vlong. The rate of water uptake was higher for Vshort, while Vlong maintained moderate and steady water uptake over time, particularly under high intensity LEDs. The reflectance spectrums changed during spathe degradation, with different responses seen in each cultivar. Reflectance spectrums showed consistent changes in the ‘red dip index’ (R800-R685), with Vshort demonstrating an increase in reflectance of red light over time while Vlong increased its absorption of red light over time. Extension of vase life under high intensity light was cultivar-dependent, revealing a previously unknown interaction between light and vase life. The absence of any interaction in the short vase life cultivar suggests that this mechanism is linked to genotypic differences in vase life, while the contrasting reflectance profiles suggest that pigment turnover is important for regulating this mechanism
A study of the genetics of resistance to bacterial blight disease (C.A. Xanthomonas Campestris PV. dieffenbachiae) and other horticultural characteristics in the anthurium andraeanum (hort.)
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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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