1,723,001 research outputs found
NS H 7822, hibrid suncokreta
No full textNS H 7822 je hibrid suncokreta (Helianthus annuus L.) priznat od strane Uprave za zaštitu bilja Ministarstva poljoprivrede, šumarstva i vodoprivrede Republike Srbije.NS H 7822 is a registered newly-developed sunflower (Helianthus annuus L.) hybrid released by the Plant Protection Directorate of the Ministry of Agriculture, Forestry and Water Management of the Republic of Serbia.Rešenje broj 320-44-2848/2/2020-11 od 20.01.2022
The exopolysaccharide production by Cyanothece sp. PCC 7822 through an adapted metabolism
Get PDFThe research is a part of the Algotech project based on the production by Cyanobacteria of high-added value products. In details, we investigate exopolysaccharide production by Cyanobacteria because of their properties and applications in cosmetics, medicine or food industries. Cyanothece sp. PCC 7822 was selected due to its ability to produce high rate of EPS. This study focuses on the impact of culture conditions such as light intensity and cycle, nitrogen source, temperature on the EPS production. Cyanothece sp. PCC 7822 grows similarly in presence of N2 or NO3- (17.6mM). Microscopic EPS examination with alcian blue shows the production of large amount of EPS and suggests the presence of sulphated and carboxylic groups in their composition. This bacterium Cyanothece sp. PCC 7822 shows its full potential by its EPS composed of carboxylic and especially sulphated group which is not the case with microalgae.Plateforme intégrée pour l'étude de la filière microalgue - Région wallonn
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
EPS production by Cyanobacteria: First insight in Cyanothece sp. PCC 7822 metabolism
Get PDFThe present research is a part of the Algotech project based on high-added value compounds production by Microalgae/Cyanobacteria. In this context, we investigate exopolysaccharide production by Cyanobacteria because of their properties and applications in cosmetics, medicine or food industries. In addition, the use of these organisms for EPS production has numerous positive aspects compared to microalgae or plants as high growth rate, easier manipulation by genetic engineering or economical costs of production.
Cyanothece sp. PCC 7822, an unicellular diazotrophic cyanobacterium, was selected due to its ability to produce high rate of EPS. This study focuses on the impact of culture conditions on the bacterium metabolism and EPS production. Four different N sources (NaNO3, NH4Cl, Urea and atmospheric N2 at 17 mM in term of N) are tested in continuous light or in 12h/12h light/dark cycle.
First results indicate that NaNO3 as N source induces the best growth in the 2 light conditions tested. The strain is also able to growth in presence of ammonium but not urea even if urease genes are presents in the genome. Observation of EPS by alcian blue staining indicates the presence of carboxylic and sulphated groups in their composition. Variation of EPS configuration according light parameters and N sources is highlighted which could be related to changes in exopolysaccharide composition. Moreover, EPS configuration seems also to change over the growth in a same condition. Furthermore, pigments profile has been done in order to characterize the strain PCC 7822 and standardize EPS concentration.
In the frame of a project implicated in microalgal energetics and biomass promotion, this work targets the EPS production by Cyanothece sp. PCC 7822 by using innovative processes. This bacterium Cyanothece sp. PCC 7822 shows its full potential by its EPS composed of carboxylic and especially sulphated group which is not the case with microalgae. In fine, this particular composition leads to saccharides with interesting industrial properties.Plateforme intégrée pour l'étude de la filière microalgue - Région wallonn
The exopolysaccharide production by Cyanothece sp. PCC 7822 through an adapted metabolism
Get PDFIntroduction
The present research is a part of the Algotech project based on the production by Microalgae/Cyanobacteria in order to obtain high-added value products. In this context, we investigate exopolysaccharide production by Cyanobacteria because of their properties and applications in cosmetics, medicine or food industries.
Methods
Cyanothece sp. PCC 7822 was selected due to its ability to produce high rate of EPS. This cyanobacterium is an unicellular diazotrophic bacterium able to grow in continuous light or in light/dark cycle. This study focuses on the impact of culture conditions such as light intensity and cycle, nitrogen source, temperature on the EPS production. The effects on the bacterial metabolism and the EPS composition are analysed through different axes: phenotypical, biochemical, proteomics (mass spectrometry) and metabolomics (metabolic flux, NMR). Firstly, bacterial growth under light/dark cycles with different nitrogen sources was tested (N2, NO3-, NH4Cl and urea). Simultaneously, EPS production demonstrated by two types of alcian blue staining was analysed.
Results
As shown in the figure 1, Cyanothece sp. PCC 7822 grows similarly in presence of N2 or NO3- (17.6mM).
Microscopic EPS examination with both specific dyes shows the production of large amount of extracellular EPS and suggests the presence of sulphated and carboxylic groups in EPS composition (Figure 2).
Moreover, optimisations of EPS alkaline extraction and colorimetric quantitation protocols (phenol sulfuric and anthrone method) have been achieved.
Discussion
In the frame of a project implicated in microalgal energetics and biomass promotion, this work targets the EPS production by Cyanothece sp. PCC 7822 by using innovative processes. This bacterium Cyanothece sp. PCC 7822 shows its full potential by its EPS composed of carboxylic and especially sulphated group which is not the case with microalgae. In fine, this particular composition leads to saccharides with interesting industrial properties.Plateforme intégrée pour l'étude de la filière microalgue - Région wallonn
The exopolysaccharide production by Cyanothece sp. PCC 7822 through an adapted metabolism
Get PDFThe present research is a part of the Algotech project based on high-added value compounds production by Microalgae/Cyanobacteria. In this context, we investigate exopolysaccharide production by Cyanobacteria because of their properties and applications in cosmetics, medicine or food industries. In addition, the use of these organisms for EPS production has numerous positive aspects compared to microalgae or plants as high growth rate, easier manipulation by genetic engineering or economical costs of production.
Cyanothece sp. PCC 7822, an unicellular diazotrophic cyanobacterium, was selected due to its ability to produce high rate of EPS. This study focuses on the impact of culture conditions on the bacterium metabolism and EPS production. Four different N sources (NaNO3, NH4Cl, Urea and atmospheric N2 at 17 mM in term of N) are tested in continuous light or in 12h/12h light/dark cycle.
First results indicate that NaNO3 as N source induces the best growth in the 2 light conditions tested. The strain is also able to growth in presence of ammonium but not urea even if urease genes are presents in the genome. Observation of EPS by alcian blue staining indicates the presence of carboxylic and sulphated groups in their composition. Variation of EPS configuration according light parameters and N sources is highlighted which could be related to changes in exopolysaccharide composition. Moreover, EPS configuration seems also to change over the growth in a same condition. Furthermore, pigments profile has been done in order to characterize the strain PCC 7822 and standardize EPS concentration.
In the frame of a project implicated in microalgal energetics and biomass promotion, this work targets the EPS production by Cyanothece sp. PCC 7822 by using innovative processes. This bacterium Cyanothece sp. PCC 7822 shows its full potential by its EPS composed of carboxylic and especially sulphated group which is not the case with microalgae. In fine, this particular composition leads to saccharides with interesting industrial properties.Plateforme intégrée pour l'étude de la filière microalgue - Région wallonn
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
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