1,721,031 research outputs found
A bacterial consortium for treatment of Fat, Oil, and Grease (FOGs) in wastewater treatment plants
Full text linkFats, oils and greases (FOG), CER 190809, in wastewater create problems including the
production of foul odours, the blockage of sewer lines and interference with the proper operation
of sewage treatment works. Removal of FOG is thus critically important to ensure that wastewater
is disposed of efficiently and economically. In this study, 232 bacterial strains were isolated and
screened for the ability to degrade lipids from a specialized treatment plant, where a enhanced
FOG degradation activity had been detected. Enrichment cultures on oily substrates, followed by
isolation on selective media for lipase producing bacteria, and enzymatic methods were used to
screen lipolytic microorganisms. In a second step, the lipolytic bacteria were analyzed using a
colorimetric assay to detect the transesterification activity of para-nitrophenyl-palmitate. Four best
performing lipid-degrading bacteria were identified by 16SrDNA sequencing, and investigated for
application in treatment of lipids-contaminated wastewater, in Sequencing Batch Reactor (SBR)
pilot plant. The FOG biodegradation efficiency was evaluated after 10 days using the gravimetric
method for quantitative determination of total oily substances. The bacterial strains were Gram
negative affiliated to Serratia, Aeromonas, Pedobacter genera. The Bacterial consortium was
able to degrade 76% of FOG in 10 days treatment. The strains are be of great interest at industrial
scale to increase the removal of FOG in wastewater treatment plants, and directly in the waste
storage tanks at catering establishments, to reduce the polluting load before transfer to the
disposal plan. The process of bioaugmentation using the FOG degrading consortium was recently
patented (n°812021000056699
Innovative ready to use carrier-bacteria devices for bioremediation of oil contaminated water
Full text linkBioremediation, that uses microorganisms to remove environmental pollutants, is the best way of restoring
the environment due to its low cost and sustainability. Immobilization of microorganisms capable of
degrading specific contaminants significantly promotes bioremediation processes. An innovative ready to
use bioremediation system to clean up oil-contaminated water was developed immobilizing highly
performant marine and soil HC degrading bacteria, on biodegradable oil-absorbing carriers. Two soil
Actinobacteria (Gordonia sp. SoCg, Nocardia sp. SoB) and two marine Gammaproteobacteria (Alcanivorax
sp. SK2, Oleibacter sp.5), were immobilized on biopolymeric membranes prepared by electrospinning
(polylactic acid, PLA and polycaprolactone, PCL). These carriers are characterized by high uptake capacity,
oil retention, buoyancy, durability, reusability and recoverability of the oil absorbed. The morphology of the
carriers and microbial adhesion and proliferation were evaluated using scanning electron microscopy (SEM).
A high capacity of adhesion and proliferation of bacterial cells was observed on membranes after 5 days. The
bioremediation efficiency of the carrier-bacteria systems was tested on crude oil by GC-FID analysis and
compared whit planktonic cells. The bacterial immobilization on PLA and PCL membranes was a
promoting factor for biodegradation, increasing hydrocarbon removal up to 20%, in respect to planktonic
cells. Biofilm-mediated bioremediation is a versatile tool to be developed for in situ and ex situ
bioremediation of aquatic systems. Several applications can be designed to exploit both the high oil uptake
capacity of the carriers, and the biodegradation potential of autochtonous microrganisms and/or of selected
microorganisms that are immobilized on the carriers before exposure to the contaminated site
DIVERSITY OF ARBUSCULAR MYCORRHIZAL FUNGI (AMF) OF ZELKOVA SICULA (DI PASQUALE GARFÌ & QUÉZEL 1992), AN ENDANGERED AND ENDEMIC TREE FROM SICILY, ITALY
No full textHigh-Performance PCR for Alleles Discrimination of Chromo-Helicase-DNA Binding Protein (CHD1) Gene in Bird Sexing
Full text linkGenetic analyses aiming at assessing the presence of specific sequences or alleles are often carried out by PCR. Sexing of most birds is nowadays based on PCR with “universal” primers and relies on the assessment of the presence of the sex-linked CHD1-Z and -W alleles. The entire workflow is relatively time-consuming, especially for batch analyses, whereas methods that allow carrying out the entire procedure in a short time are highly desirable. The only method for outdoor analyses reported so far relies on LAMP; however; it fails to work properly in Procellariiformes. Besides improving the LAMP test; we have developed a PCR-based DNA amplification procedure (named high-performance PCR); whose unique features allow it to outperform standard PCR; making possible the direct, in-tube visual reading of results. We tested it with specifically designed Procellariiformes-targeted primer sets for rapid sexing of the birds using fluorimetric detection. The protocol, combined with rapid DNA extraction, allows for fast reading of results without electrophoresis within less than 1 h from sampling. The technique could be extended to other species, as well as to many other applications
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
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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