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Subcritical water extraction of antioxidant compounds from canola mealHassas Roudsari, Majid 04 December 2007
Antioxidant compounds were extracted from canola meal by subcritical water extraction (SWE), hot water (80°C) extraction and ethanolic (95%) extraction. The highest extract yields were obtained with SWE at 160°C, and the lowest with ethanolic extraction (SWE 160°C > SWE sequential > SWE 135°C > SWE 110°C = hot water extraction > ethanolic extraction). Ethanolic extracts exhibited the highest total phenolics contents and Trolox equivalent antioxidant capacity (TEAC) values on a per gram of extract basis, and hot water extracts, the lowest (ethanolic extraction > SWE 110°C > SWE 160°C > hot water extraction). Extraction pressure (3.44-6.89 MPa) had no effect on the yields, total phenolics contents or TEAC values of extracts from SWE. The use of buffered water (pH 2-8) for SWE increased extract yield but had adverse effects on the total phenolics contents and TEAC values of extracts. No increase in efficacy of SWE at 110 or 160°C was observed at extraction times longer than 25-30 min.
The total phenolics contents and antioxidant capacities of extracts were assessed by the total phenolics assay, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method, TEAC method, the β-carotene-linoleic acid (linoleate) model system, the reducing power assay and the stripped oil model system. Ethanolic extracts exhibited the highest total phenolic contents and antioxidant capacities on a per gram of extract basis. Subcritical water extraction at 160°C exhibited the highest total phenolic contents and antioxidant capacities on a per gram of meal basis. Results from the total phenolics assay and the antioxidant capacity assays were significantly correlated, with the exception of those from the stripped oil model system.
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A Framework for Logical Structure Extraction from Software Requirements DocumentsRauf, Rehan January 2011 (has links)
General purpose rich-text editors, such as MS Word are often used to author software requirements specifications. These requirements specifications contain many different logical structures, such as use cases, business rules and functional requirements. Automated recognition and extraction of these logical structures is necessary to provide useful automated requirements management features, such as automated traceability, template conformance checking, guided editing and interoperability with sophisticated requirements management tools like Requisite Pro. The variability among instances of these logical structures and their attributes poses many challenges for their accurate recognition and extraction. The thesis provides a framework for the extraction of logical structures from software requirements documents. The framework models information about style, structure, and attributes of the logical structures and uses the defined meta-model to extract instances of logical structures. A meta-model also incorporates information about the variability present in the instances. The framework includes an extraction tool, ET, that reads the meta-model and extracts instances of modelled logical structures from the documents. The framework is evaluated on a collection of real-world software requirements documents. Using the framework, different logical structures can be extracted with high precision and recall, each close to 100%. The performance of the extraction tool is acceptable for fast extraction of logical structures from documents with extraction times ranging from a few milliseconds to a few seconds.
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Subcritical water extraction of antioxidant compounds from canola mealHassas Roudsari, Majid 04 December 2007 (has links)
Antioxidant compounds were extracted from canola meal by subcritical water extraction (SWE), hot water (80°C) extraction and ethanolic (95%) extraction. The highest extract yields were obtained with SWE at 160°C, and the lowest with ethanolic extraction (SWE 160°C > SWE sequential > SWE 135°C > SWE 110°C = hot water extraction > ethanolic extraction). Ethanolic extracts exhibited the highest total phenolics contents and Trolox equivalent antioxidant capacity (TEAC) values on a per gram of extract basis, and hot water extracts, the lowest (ethanolic extraction > SWE 110°C > SWE 160°C > hot water extraction). Extraction pressure (3.44-6.89 MPa) had no effect on the yields, total phenolics contents or TEAC values of extracts from SWE. The use of buffered water (pH 2-8) for SWE increased extract yield but had adverse effects on the total phenolics contents and TEAC values of extracts. No increase in efficacy of SWE at 110 or 160°C was observed at extraction times longer than 25-30 min.
The total phenolics contents and antioxidant capacities of extracts were assessed by the total phenolics assay, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method, TEAC method, the β-carotene-linoleic acid (linoleate) model system, the reducing power assay and the stripped oil model system. Ethanolic extracts exhibited the highest total phenolic contents and antioxidant capacities on a per gram of extract basis. Subcritical water extraction at 160°C exhibited the highest total phenolic contents and antioxidant capacities on a per gram of meal basis. Results from the total phenolics assay and the antioxidant capacity assays were significantly correlated, with the exception of those from the stripped oil model system.
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Optimized procedures for extractioin, purification and characterization of exopolymeric substances (eps) from two bacteria (sagittula stellata and pseudomonas fluorescens biovar ii) with relevance to the study of actinide binding in aquatic environmentsXu, Chen 15 May 2009 (has links)
The extracellular polymeric substances (EPS) of marine bacterium Sagittula stellata
and soil bacterium Pseudomonas fluorescens Biovar II, were extracted by six methods
referred to the bibliography, efficacies of which were compared based on the EPS yield,
composition as well as cell disturbance. Purification methods on these EPS were also
improved, which proved to be more cost-effective and involve less interference from
broth, compared to previous methods. Size exclusion chromatography (SEC) proved to
be a useful tool, providing the “fingerprints” of the EPS extracted by different methods
or after each purification step. Studies of the EPS production and composition at
different growth stages provided abundant information and a basis for further in-depth
studies. Results from SEC demonstrated that bacterial EPS had a constant molecular
weight distribution all through the life but with various polymers in different proportions.
Three fractions were successfully isolated by a combination of SEC and anion exchange
chromatography for “non-attched” EPS produced by Pseudomonas flurorescens Biovar
II. Protein turned out to be a major component of EPS in their native states, which was mixed with the broth material and couldn’t be recognized previously. The EPS harvested
at the optimal time of the bacterial life was purified according to the improved method
and was more enriched in polysaccharides, with small amounts of proteins, giving the
molecules amphiphilic properties. In addition, simultaneous determination of neutral
sugars and uronic acids by GC-EI-MS provided more information on the
monosaccharide composition of the exopolysaccharides. Isoelectric focusing (IEF)
spectra of the bacterial EPS spiked with Pu/Th, and Pu-enriched Rocky Flats
Environmental Technology Site (RFETS) soil organic colloid spiked with Th showed
similar activity distributions of both actinides along the pH gradient, with the activities
of both actinides focusing on the low pH region. Characterizations of this Pu-enriched
IEF extract from RFETS soil by spectrophotometric methods and ATR-FTIR indicated
the co-presence of lipids, proteins and polysaccharides, in contrast to the bacterial EPS,
which showed a simpler composition. This suggests that Th/Pu binding to organic
macromolecules is more determined by the availability of binding functional groups
rather than the exact specific compounds.
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Representing Information Collections for Visual CognitionKoh, Eunyee 15 May 2009 (has links)
The importance of digital information collections is growing. Collections are
typically represented with text-only, in a linear list format, which turns out to be a
weak representation for cognition. We learned this from empirical research in cognitive
psychology, and by conducting a study to develop an understanding of current
practices and resulting breakdowns in human experiences of building and utilizing collections.
Because of limited human attention and memory, participants had trouble
finding specific elements in their collections, resulting in low levels of collection utilization.
To address these issues, this research develops new collection representations
for visual cognition. First, we present the image+text surrogate, a concise representation
for a document, or portion thereof, which is easy to understand and think
about. An information extraction algorithm is developed to automatically transform
a document into a small set of image+text surrogates. After refinement, the average
accuracy performance of the algorithm was 90%. Then, we introduce the composition
space to represent collections, which helps people connect elements visually in a
spatial format. To ensure diverse information from multiple sources to be presented
evenly in the composition space, we developed a new control structure, the ResultDis-
tributor. A user study has demonstrated that the participants were able to browse
more diverse information using the ResultDistributor-enhanced composition space.
Participants also found it easier and more entertaining to browse information in this
representation. This research is applicable to represent the information resources in contexts such as search engines or digital libraries. The better representation will enhance
the cognitive efficacy and enjoyment of people’s everyday tasks of information
searching, browsing, collecting, and discovering.
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Caractérisation de la production et optimisation du processus d'extraction des colorants de la plante de An̆il (Indigofera suffruticosa Mill)Sandoval-Salas, Fabiola Vilarem, Gérard Gschaedler Mathis, Anne. January 2006 (has links)
Reproduction de : Thèse de doctorat : Sciences des agroressource : Toulouse, INPT : 2005. / Titre provenant de l'écran-titre. Bibliogr. 122 réf.
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Etude des facteurs de risque d'échec d'extraction instrumentale par la ventouse obstétricaleBarré, Maxime Boog, Georges. January 2008 (has links)
Reproduction de : Thèse d'exercice : Médecine. Gynécologie Obstétrique : Nantes : 2008. / Bibliogr.
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Méthodologie pour le passage en continu d'extraction de solute à partir de matière végétalePoirot, Rachel Gourdon, Christophe January 2008 (has links)
Reproduction de : Thèse de doctorat : Génie des procédés et de l'environnement : Toulouse, INPT : 2007. / Titre provenant de l'écran-titre. Bibliogr. 50 réf.
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Que faire après un échec de ventouse ?Puren, Milène Boog, Georges. January 2008 (has links)
Reproduction de : Mémoire de Sage-femme : Médecine : Nantes : 2008. / Bibliogr.
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The effect of solvents and processing conditions on the solvent extraction of coalBhole, Manish R. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xiii, 122 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 100-103).
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