1,720,969 research outputs found
Vicia: a green bridge to clean up polluted environments
No full textVicia species, commonly known as vetches, include legume plants which nowadays can be found in many countries around the world. Their use to improve soil health and productivity is crucial in management schemes that make sustainable agriculture possible, but they can also play a part in the phytoremediation of polluted environments. Furthermore, they harbor a large community of rhizospheric microorganisms, such as biodegradative bacteria and plant growth–promoting rhizobacteria, which can help to increase phytoremediation efficiency. Their mutualistic association with Rhizobium sp. has also been proposed as an attractive bioremediation tool. Thus, Vicia species could make a remarkable difference in the ecological restoration of polluted soils, thanks to their dual role as cover crops and phytoremediator plants. This mini-review discusses recent advances in the use of Vicia. Challenges and opportunities connect with the application of these species will also be revised, as well as aspects that remain to be explored.Fil: Ibañez, Sabrina Guadalupe. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Medina, Maria Ines. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentin
Phenol tolerance, changes of antioxidative enzymes and cellular damage in transgenic tobacco hairy roots colonized by arbuscular mycorrhizal fungi
Full text linkPhytoremediation has been recognized as a cheap and eco-friendly technology which could be used for the remediation of organic pollutants, such as phenolic compounds. Besides, the extent to which plants react to environmental pollution might depend on rhizosphere processes such as mycorrhizal symbiosis. In the present work, phenol tolerance of transgenic tobacco hairy roots (HR), namely TPX1, colonized with an arbuscular mycorrhizal fungus (AMF) was studied. However, the question is whether AMF symbiosis can moderate adverse effects of phenol to the plant tissues. Thus, the antioxidative response as well as parameters of oxidative damage, like malondialdehyde (MDA) content, were determined. Antioxidative enzymes such as peroxidase, superoxide dismutase, ascorbate peroxidase were higher in TPX1 HR colonized with AMF, compared to wild type HR colonized by AMF, in the presence of increasing concentrations of the pollutant. Besides, MDA levels remained unaltered in TPX1 HR associated with AMF treated with the xenobiotic. These results, suggested that this culture could tolerate phenol and moreover, it has an efficient protective mechanism against phenol-induced oxidative damage, which is of great importance in the selection of species with remediation capacities. Thus, transgenic HR colonized with AMF could be considered as an interesting model system to study different processes which play a key role in the phytoremediation of organic pollutants.Fil: Ibañez, Sabrina Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Medina, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin
Phytoremediation of Phenol at pilot scale by tobacco hairy roots
Full text linkPhenol is a toxic compound commonly found in the wastewater released from several industries. In the present work, we optimized the use of tobacco hairy roots (HRs), wild type (WT) and double transgenic (DT) for two peroxidases, as an alternative strategy for the treatment of this pollutant. The optimal conditions for the removal process were evaluated using different phenol (100-800 mg L-1) and H2O2 (2,5-10 mM) concentrations. Tobacco HRs were able to remove solutions with increasing phenol concentrations. Regarding the effect of exposition time, prolonged time of treatment improved phenol remediation when high pollutant concentrations were used. A decrease in basic peroxidase (Px) isoenzymes was detected after phenol treatment. Kinetic studies were performed using different Px extracts, such as soluble Px (SPx) and ionically bound Px (IBPx) from WT and DT HRs. SPx and IBPx extracts from DT HRs, showed high affinity towards phenol as substrate and higher catalytic efficiency than extracts derived from WT HRs. Moreover, IBPx extract from DT HRs, showed the highest catalytic efficiency, demonstrating that these HRs could provide an adequate matrix for the successful phenol removal.Fil: Sosa Alderete, Lucas Gastón. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Ibañez, Sabrina Guadalupe. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Medina, Maria Ines. Universidad Nacional de Río Cuarto; Argentin
Vicia sativa–rhizospheric bacteria interactions to improve phenol remediation
Full text linkThe aim of this study was to evaluate whether the interaction of Vicia sativa with a bacterial strain capable of using phenol as sole carbon and energy sources can moderate adverse effects of this pollutant in plant tissues. A bacterial strain identified as Bacillus sp., isolated from a heavily polluted environment, was inoculated at different stages of growth. In root elongation assay, inoculated seeds showed higher values of relative root elongation and germination index than uninoculated ones in the presence of high phenol concentrations. Thus, common vetch–Bacillus sp. association could be important at the first stages of development allowing this plant to grow in highly polluted environments. Besides, phenol removal was largely accelerated in phenol-spiked soils, after 48 h of treatment with uninoculated/inoculated plants rather than by adsorption or biodegradation of the bacterial strain. Peroxidase and ascorbate peroxidase activities increased significantly in uninoculated plants, while superoxide dismutase activity, chlorophyll, malondialdehyde, and H2O2 levels of aerial parts remained unaltered in uninoculated/inoculated plants treated with the pollutant, demonstrating that the efficient response to oxidative damage did not depend on the inoculation.Fil: Ibañez, Sabrina Guadalupe. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Merini, Luciano Jose. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología Industrial y Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barros, Germán Gustavo. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Medina, Maria Ines. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Transgenic plants and hairy roots: exploiting the potential of plant species to remediate contaminants
Full text linkPhytoremediation has emerged as an attractive methodology to deal with environmental pollution, which is a serious worldwide problem. Although important advances have been made in this research field, there are still some drawbacks to become a widely used practice, such as the limited plant's metabolic rate and their difficulty to break down several organic compounds or to tolerate/accumulate heavy metals. However, biotechnology has opened new gateways in phytoremediation research by offering the opportunity for direct gene transfer to enhance plant capabilities for environmental cleanup. In this context, hairy roots (HRs) have emerged as an interesting model system to explore the potential of plants to remove inorganic and organic pollutants. Besides, their use in rhizoremediation studies has also been explored. In this minireview we will discuss the most recent advances using genetic engineering for enhancing phytoremediation capabilities of plants and HRs.Fil: Ibañez, Sabrina Guadalupe. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Ontañon, Ornella Mailén. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Suman, Jachym. University of Chemistry and Technology; República ChecaFil: Medina, Maria Ines. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Macek, Tomas. University of Chemistry and Technology; República ChecaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentin
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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