1,720,963 research outputs found
Gene expression profiling in zebrafish embryos exposed to diclofenac, an environmental toxicant
No full textPharmaceuticals are continually released in the
environment and therefore pollution from drugs is a
pressing problem in the environment. Diclofenac, 2-[(2,6-
dichlorophenyl)amino]phenylacetic acid is a FDA
approved non-steroidal anti-inflammatory drug (NSAID)
for the treatment of inflammation. This pharmaceutical has
been found as pollutant in superficial waters. Danio rerio
(zebrafish) embryo has been used as a model organism for
acute pollutant toxicity tests in order to identify morphological
alterations in development and death rate. Through
the combination of mRNA differential display and quantitative
Real Time experiments, we analyzed the alterations
of gene expression in zebrafish embryos left to develop in
the presence of diclofenac and thereby assess the molecular
mechanism involved in ecotoxicity of diclofenac polluted
waters. This approach, in embryos exposed to 1.25 mg/l
drug for 48 h, allowed identifying 36 different genes, with
both known and unknown functions, whose transcription is
differentially regulated. The identity and ontological classification
of these genes is presented. The wide variety of
functional classes of transcripts isolated in this screen
reflects the diverse spectrum of influences operating across
diclofenac exposure. Of these 36 genes, several have been
selected for detailed quantitative Real Time analysis to
validate the screen. Our results, for the first time, provide
an insight into some of the varied and novel molecular networks following zebrafish exposure to diclofenac polluted
waters
Gene expression profiling in zebrafish embryos exposed to diclofenac, an environmental toxicant
No full textPharmaceuticals are continually released in the environment and therefore pollution from drugs is a pressing problem in the environment. Diclofenac, 2-[(2,6-dichlorophenyl) amino] phenylacetic acid is a FDA approved non-steroidal anti-inflammatory drug (NSAID) for the treatment of inflammation. This pharmaceutical has been found as pollutant in superficial waters. Danio rerio (zebrafish) embryo has been used as a model organism for acute pollutant toxicity tests in order to identify morphological alterations in development and death rate. Through the combination of mRNA differential display and quantitative Real Time experiments, we analyzed the alterations of gene expression in zebrafish embryos left to develop in the presence of diclofenac and thereby assess the molecular mechanism involved in ecotoxicity of diclofenac polluted waters. This approach, in embryos exposed to 1.25 mg/l drug for 48 h, allowed identifying 36 different genes, with both known and unknown functions, whose transcription is differentially regulated. The identity and ontological classification of these genes is presented. The wide variety of functional classes of transcripts isolated in this screen reflects the diverse spectrum of influences operating across diclofenac exposure. Of these 36 genes, several have been selected for detailed quantitative Real Time analysis to validate the screen. Our results, for the first time, provide an insight into some of the varied and novel molecular networks following zebrafish exposure to diclofenac polluted waters
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
Uranium groundwater monitoring and seismic analysis: a case study of the Gran Sasso hydrogeological basin, Italy
No full textAn Ecotoxicological Approach to Evaluate the Environmental Quality of Inland Waters.
No full textWater is traditionally considered a renewable resource as the quantity theoretically available
depends essentially on meteoric water contributions. Modern theories consider river
ecosystem as a central element of the environment but, actually, water ecosystems are more
and more polluted because of agricultural and industrial activities. In Italy, where there is a
widespread urbanization, most part of river ecosystems are exposed to a severe risk of
damage, with consequent loss of biodiversity. The institution of national and regional parks
makes possible the preservation of significant natural value areas. In 1974, the UNESCO
established a “World Network of Biosphere Reserves” (WNBR) aimed to preserve areas,
where there is a close relation between man and nature, through environmental preservation
and sustainable development (UNESCO,2010). Nevertheless, a constant monitoring along the
whole watercourse (from spring to mouth) is needed as, even in a protected area, human
activities could cause, directly or indirectly, damages to valuable ecosystems
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
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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