Deterioro del aceite durante el almacenamiento de los hígados de merluza en comparación con el del aceite extraído de ellos

Hake liver (Merluccis hubbsi) is a by-product of the fillet industry and is used as a source of oil . In the present paper the oil content of livers stored at 4ºC and -20ºC is studied compared to that of the oil extracted from livers and stored under the same conditions. Oil contained in livers stored at -20ºC was oxidized in two weeks; the oil extracted from livers and stored under the same conditions was preserved for several months. The problem is that once the oil becomes deteriorated in livers it is not possible to stabilize it by adding antioxidants. Thus it is necessary to store livers at temperatures lower than -20ºC, to extract the oil as soon as possible, to add the correct antioxidants and to store it under refrigeration, in order to obtain a high quality oil.Los hígados de merluza (Merluccius hubbsi) son un subproducto de la industria fileteadora y se utilizan como fuente de aceite. En este trabajo se estudia el aceite contenido en dichos hígados durante su almacenamiento a 4ºC y a -20ºC frente a la del aceite extraído de ellos y guardado en iguales condiciones. El aceite contenido en los hígados almacenados a -20ºC, se oxida en un par de semanas; el aceite extraído de ellos y almacenado en iguales condiciones se conserva durante varios meses. El problema principal radica en que, una vez que el aceite se deteriora en los hígados, no es posible estabilizarlo por el agregado de antioxidantes. Para obtener un aceite de buena calidad es imprescindible que los hígados se almacenen a una temperatura menor de -20ºC, que su aceite se extraiga lo antes posible, que se le adicione de antioxidantes adecuados y que se le almacene refrigerad

Constructing a biodiversity terminological inventory.

The increasing growth of literature in biodiversity presents challenges to users who need to discover pertinent information in an efficient and timely manner. In response, text mining techniques offer solutions by facilitating the automated discovery of knowledge from large textual data. An important step in text mining is the recognition of concepts via their linguistic realisation, i.e., terms. However, a given concept may be referred to in text using various synonyms or term variants, making search systems likely to overlook documents mentioning less known variants, which are albeit relevant to a query term. Domain-specific terminological resources, which include term variants, synonyms and related terms, are thus important in supporting semantic search over large textual archives. This article describes the use of text mining methods for the automatic construction of a large-scale biodiversity term inventory. The inventory consists of names of species, amongst which naming variations are prevalent. We apply a number of distributional semantic techniques on all of the titles in the Biodiversity Heritage Library, to compute semantic similarity between species names and support the automated construction of the resource. With the construction of our biodiversity term inventory, we demonstrate that distributional semantic models are able to identify semantically similar names that are not yet recorded in existing taxonomies. Such methods can thus be used to update existing taxonomies semi-automatically by deriving semantically related taxonomic names from a text corpus and allowing expert curators to validate them. We also evaluate our inventory as a means to improve search by facilitating automatic query expansion. Specifically, we developed a visual search interface that suggests semantically related species names, which are available in our inventory but not always in other repositories, to incorporate into the search query. An assessment of the interface by domain experts reveals that our query expansion based on related names is useful for increasing the number of relevant documents retrieved. Its exploitation can benefit both users and developers of search engines and text mining applications

MACSE: Multiple Alignment of Coding SEquences Accounting for Frameshifts and Stop Codons

Until now the most efficient solution to align nucleotide sequences containing open reading frames was to use indirect procedures that align amino acid translation before reporting the inferred gap positions at the codon level. There are two important pitfalls with this approach. Firstly, any premature stop codon impedes using such a strategy. Secondly, each sequence is translated with the same reading frame from beginning to end, so that the presence of a single additional nucleotide leads to both aberrant translation and alignment

Identification of Pathogenicity-Related Genes in the Vascular Wilt Fungus Verticillium dahliae by Agrobacterium tumefaciens-Mediated T-DNA Insertional Mutagenesis

Verticillium dahliae is the causal agent of vascular wilt in many economically important crops worldwide. Identification of genes that control pathogenicity or virulence may suggest targets for alternative control methods for this fungus. In this study, Agrobacteriumtumefaciens-mediated transformation (ATMT) was applied for insertional mutagenesis of V. dahliae conidia. Southern blot analysis indicated that T-DNAs were inserted randomly into the V. dahliae genome and that 69% of the transformants were the result of single copy T-DNA insertion. DNA sequences flanking T-DNA insertion were isolated through inverse PCR (iPCR), and these sequences were aligned to the genome sequence to identify the genomic position of insertion. V. dahliae mutants of particular interest selected based on culture phenotypes included those that had lost the ability to form microsclerotia and subsequently used for virulence assay. Based on the virulence assay of 181 transformants, we identified several mutant strains of V. dahliae that did not cause symptoms on lettuce plants. Among these mutants, T-DNA was inserted in genes encoding an endoglucanase 1 (VdEg-1), a hydroxyl-methyl glutaryl-CoA synthase (VdHMGS), a major facilitator superfamily 1 (VdMFS1), and a glycosylphosphatidylinositol (GPI) mannosyltransferase 3 (VdGPIM3). These results suggest that ATMT can effectively be used to identify genes associated with pathogenicity and other functions in V. dahliae

Modificaciones de la forma de la colonia de B. anthracis por acción del suero específico

Fil.: Sordelli, A. Instituto Bacteriológico. Departamento Nacional de Higiene; Argentina

Modificaciones de la forma de la colonia de B. anthracis por acción del suero específico

Fil.: Sordelli, A. Instituto Bacteriológico. Departamento Nacional de Higiene; Argentina