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Protocol development for micropropagation of Phyllanthus niruri linn. (dukung anak) via in vitro culture
Get PDFPhyllanthus niruri, commonly known as Dukung Anak or Gale of Stone, is an herbaceous plant belonging to the family Phyllanthaceae that has commonly been distributed in tropical countries, including Malaysia. Even though this plant is considered a problematic weed for farmers, it has been used traditionally to treat various ailments such as diabetes, flu, and cough. Overexploitation in Malaysia, on the other hand, has resulted in wide destruction of this plant from its natural habitat. Besides, there is no information on the production of P. niruri in Malaysia. This study has provided a solution to this problem through in vitro technology approach. Specifically, this study's objectives were to study the growth efficiency of P. niruri with different surface sterilants, to study in vitro growth responses of P. niruri towards different growth factors, and to determine the factors affecting in vitro rooting and acclimatization of P. niruri. P. niruri explant's nodal segment was prepared for surface sterilization using Clorox® and nanosilver with 10, 20, 30 (% and ppm, respectively). The aseptic culture was established with the lowest percentage of contamination, 4.44% using 30% Clorox®. The explant from the previous experiment was multiplied by different plant growth factors, which were different types of basal media and its strength, different cytokinin and its concentrations, different carbon sources and its strength, and different initial pH of basal media. Murashige and Skoog (MS) media and Gamborg B5 (B5) with the strength of half, full and double were used in the first experiment. Full-strength MS media produced a decent number of shoots with 2.33 shoots, 3.11 cm length of shoots and 27.91 number of leaves. In a subsequent experiment, MS media was supplemented with different types of cytokinin, which were 6-benzylaminopurine (BAP), kinetin (Kn), zeatin (Zn), and 2-isopentenyl adenine (2iP) with different concentrations of 2.5, 5.0, 7.5, and 10 μM. The best treatment was obtained from MS media without cytokinin (control), which produced 5.00 number of shoots, 3.68 cm length of shoot, and 27.33 number of leaves. In the next experiment, basal media were manipulated with different carbon sources like sucrose, fructose, and glucose at different concentrations of 20, 25, 30, 35, and 40 g/L. The result showed the explant in media enriched with 30 g/L of sucrose has the highest number of shoots with an average of 3.2 shoots and shoot elongation of 2.27 cm. Lastly, the initial pH media was tested at 5.2, 5.4, 5.6, 5.8, 6, and 6.2. The highest number of shoots was recorded at a pH level of 5.6 (2.93). In the last experiment, the explant was used for root induction using different auxins at different concentrations. There were indole-3-butyric acid (IBA), 1-naphthalene acetic acid (NAA), and indole-3-acetic acid (IAA) at 1.25, 2.5, and 5 μM, respectively. Media with 2.5 μM IBA produced the highest number of the shoot and the most extended length of the root with 17.92 shoots and 1.29 cm root length. Lastly, the explant was acclimatized ex vitro in different potting media; peat moss: cocopeat, peat moss: vermiculite, peat moss: perlite at a ratio of 1:1 w/w and mixed of all media peat moss: cocopeat: vermiculite: perlite at a ratio of 1:1:1:1 w/w. The plantlet in potting media consisting of peat moss: cocopeat (1:1 ratio) showed the best performance with 88% plant survival. In conclusion, protocol for micropropagation of P. niruri has been developed in this study
The Efficient and Easy Micropropagation Protocol of Phyllanthus niruri
No full textPhyllanthus niruri (P. niruri) or Dukung Anak is a herbal plant in the Phyllanthaceae family that has been used traditionally to treat various ailments such as diabetes, jaundice, flu and cough. P. niruri contains numerous medicinal benefits such as anti-tumor and anti-carcinogenic properties and a remedy for hepatitis B viral infection. Due to its beneficial properties, P. niruri is overharvested and wild plants become scarce. This study was conducted to develop an appropriate in vitro culture protocol for the mass production of P. niruri. An aseptic culture of P. niruri was established followed by multiplication of explants using different types of basal medium and its strength and plant growth regulators manipulation. This study also established the induction of in vitro rooting utilizing various types and concentrations of auxin. Treatment of Clorox® with 30% concentration showed the lowest percentage (%) of contamination, 4.44% in P. niruri culture. Nodal segments of P. niruri were successfully induced in full-strength of Murashige and Skoog (MS) basal media with 2.33 number of shoots, 3.11 cm length of shoot and 27.91 number of leaves. In addition, explants in full-strength MS media without any additional cytokinin were recorded as the optimum results for all parameters including the number of shoots (5.0 shoots), the length of shoots (3.68 cm) and the number of leaves (27.33 leaves). Treatment of 2.5 µM indole-3-butyric acid (IBA) showed the highest number of roots (17.92 roots) and root length (1.29 cm). Rooted explants were transferred for acclimatization, and the plantlet showed over 80% of survival rate. In conclusion, plantlets of P. niruri were successfully induced and multiplied via in vitro culture, which could be a step closer to its commercialization
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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