1,721,025 research outputs found
RETRACTED: Water hyacinth a potential source for value addition: An overview
No full textWater hyacinth a fresh water aquatic plant is considered as a noxious weed in many parts of the world since it grows very fast and depletes nutrients and oxygen from water bodies adversely affecting the growth of both plants and animals. Hence conversion of this problematic weed to value added chemicals and fuels helps in the self-sustainability especially for developing countries. The present review discusses the various value added products and fuels which can be produced from water hyacinth, the recent research and developmental activities on the bioconversion of water hyacinth for the production of fuels and value added products as well as its possibilities and challenges in commercialization. (C) 2017 Elsevier Ltd. All rights reserved.GR-G
Recent advances in the production of value added chemicals and lipids utilizing biodiesel industry generated crude glycerol as a substrate - Metabolic aspects, challenges and possibilities: An overview
No full textOne of the major ecological concerns associated with biodiesel production is the generation of waste/
crude glycerol during the trans-esterification process. Purification of this crude glycerol is not economically
viable. In this context, the development of an efficient and economically viable strategy would be
biotransformation reactions converting the biodiesel derived crude glycerol into value added chemicals.
Hence the process ensures the sustainability and waste management in biodiesel industry, paving a path
to integrated biorefineries. This review addresses a waste to wealth approach for utilization of crude glycerol
in the production of value added chemicals, current trends, challenges, future perspectives, metabolic
approaches and the genetic tools developed for the improved synthesis over wild type
microorganisms were described
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
Climate change and diatoms
No full textClimate change has triple-pronged effects – warming, deoxygenation, and acidification – in freshwater and marine environments, effects which have a full spectrum of impacts on primary producers. Diatoms are an appropriate model for indicating climate change effects because they are ubiquitous in aquatic ecosystems and are the most important primary producers in marine ecosystems (i.e., 40% of productivity) and contribute 20% of atmospheric oxygen, but have not been adequately studied in relation to climate change. Diatoms have numerous characteristics that can be used to measure the effects of climate change. For example, climate change may increase the relative abundance of dinoflagellates compared to diatoms, leading to more frequent occurrences of harmful algal blooms in marine ecosystems, where diatoms and dinoflagellates dominate blooms. Such blooms can have far-reaching impacts on ecosystems and can impact on humans by affecting fisheries, tourism, and other economic losses. These changing climatic scenarios may be accompanied by a change in the various life-forms of diatoms, such as a shift from mixed life-forms (undisturbed) to the dominance of pioneer and adnate diatoms (disturbed by an increase in carbon dioxide concentration) in the community. Diatoms store excess energy as lipids, and the number and biovolume of lipid bodies can be a valuable diagnostic tool for stress, including climate change. At the molecular level, organic lipid biomarkers can provide information to help decipher past and present climatic conditions, such as glaciation and deglaciation processes in polar regions. Reductions in diatom size and silica availability for frustule formation have been linked to increasing temperatures, such as those from global warming, in both freshwater and oceanic ecosystems – although not all studies are supportive. Finally, diatoms are excellent experimental organisms for indicating potential impacts of climate change on living organisms
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
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