Comparison of cubesat and microsat catastrophic failures in function of radiation and debris impact risk.

Occurrence level comparison of catastrophic failures due to radiation effects on electronic components or collision with space debris are studied in two types of satellites: cubesats and microsats. Low Earth Orbit (LEO) case studies are proposed, and the level of catastrophic failure occurrence is quantified for the same mission duration. The variation in the occurrence of failures is studied and there is a determination of which is more likely. Emphasis is placed on examining how an increase in space debris would affect the reliability of future space missions.

Identificación genética del orégano de Putre (Origanum vulgare L) mediante ITS y microsatélites, una especie reconocida en Chile con Sello de Origen / Genetic identification of the Putre's oregano (Origanum vulgare L) by ITS and microsatellites, a species recognized in Chile with Seal of Origin

Putre ́s oregano (Origanum vulgare L.) is a variety of oregano that grown in the Arica-Parinacota Region. Its organoleptic attributes and unique production conditions have earned it a certification with Geographical Indication (GI). However, the demands of the markets require a scientific-technological support for identification and authentication of materials. In this context, was proposed to identify Putre's oregano by phylogenetic relationships based on the use of molecular markers SSR and "DNA Barcode". The results showed that when comparing materials from different sources of Putre ́s oregano versus information from certified germplasms and GenBank sequences, added to the analysis with nuclear genetic markers, Putre ́s oregano corresponds to the species Origanum vulgare L. subsp virens. This precise identification will support the correct differentiation and authentication of this genotype, serving in addition to supporting the GI.

El orégano de Putre (Origanum vulgare L.) es una variedad de orégano que se cultiva en la Región de Arica y Parinacota. Sus atributos organolépticos y condiciones únicas de producción lo han hecho acreedor de una certificación con Indicación Geográfica (IG). Sin embargo, las exigencias de los mercados requieren de un respaldo científico-tecnológico de identificación y autenticación de materiales. En este contexto, se propuso identificar el orégano de Putre mediante relaciones filogenéticas a partir del uso de marcadores moleculares SSR y "DNA Barcode". Los resultados demostraron que al comparar los materiales de distintas procedencias de orégano de Putre versus la información desde germoplasmas certificados y secuencias de GenBank, sumado al análisis con marcadores genéticos nucleares, el orégano de Putre corresponde a la especie Origanum vulgare L. subsp virens. Esta identificación precisa dará soporte a la correcta diferenciación y autenticación de este genotipo, sirviendo además de apoyo a la IG.

Comparative transcriptional profiling analysis of olive ripe-fruit pericarp and abscission zone tissues shows expression differences and distinct patterns of transcriptional regulation.

BACKGROUND: In fleshy fruit, abscission of fully ripe fruit is a process intimately linked to the ripening process. In many fruit-tree species, such as olive (Olea europaea L. cv. Picual), there is a coupling of the full ripening and the activation of the abscission-zone (AZ). Although fully ripe fruit have marked physiological differences with respect to their AZs, dissimilarities in gene expression have not been thoroughly investigated. The present study examines the transcriptome of olive fruit and their AZ tissues at the last stage of ripening, monitored using mRNA-Seq. RESULTS: Roche-454 massive parallel pyrosequencing enabled us to generate 397,457 high-quality EST sequences, among which 199,075 were from ripe-fruit pericarp and 198,382 from AZ tissues. We assembled these sequences into 19,062 contigs, grouped as 17,048 isotigs. Using the read amounts for each annotated isotig (from a total of 15,671), we identified 7,756 transcripts. A comparative analysis of the transcription profiles conducted in ripe-fruit pericarp and AZ evidenced that 4,391 genes were differentially expressed genes (DEGs) in fruit and AZ. Functional categorization of the DEGs revealed that AZ tissue has an apparently higher response to external stimuli than does that of ripe fruit, revealing a higher expression of auxin-signaling genes, as well as lignin catabolic and biosynthetic pathway, aromatic amino acid biosynthetic pathway, isoprenoid biosynthetic pathway, protein amino acid dephosphorylation, amino acid transport, and photosynthesis. By contrast, fruit-enriched transcripts are involved in ATP synthesis coupled proton transport, glycolysis, and cell-wall organization. Furthermore, over 150 transcripts encoding putative transcription-factors (TFs) were identified (37 fruit TFs and 113 AZ TFs), of which we randomly selected eight genes and we confirmed their expression patterns using quantitative RT-PCR. CONCLUSION: We generated a set of EST sequences from olive fruit at full ripening, and DEGs between two different olive tissues, ripe fruit and their AZ, were also identified. Regarding the cross-talk between fruit and AZ, using qRT-PCR, we confirmed a set of TF genes that were differentially expressed, revealing profiles of expression that have not previously been reported, this offering a promising beginning for studies on the different transcription regulation in such tissues.

Mature fruit abscission is associated with up-regulation of polyamine metabolism in the olive abscission zone.

This study investigates whether, and how, polyamines (PAs) are involved in mature fruit abscission of olive (Olea europaea L.). Physiological abscission was studied in relation to the activation of the abscission zone (AZ), located between fruit and peduncle, from two olive cultivars where the breakstrength profiles and the scanning electron micrographs illustrated differences in the abscission program, under natural conditions, of mature fruit. The localization and activities of diamine oxidase (DAO), polyamine oxidase (PAO) and PA biosynthetic enzymes, together with PA content were investigated in the fruit AZ during development and abscission. The activities of arginine decarboxylase and S-adenosyl-l-methionine decarboxylase in the fruit AZ were significantly increased and decreased, respectively, by mature fruit abscission, in good agreement with the rise in free putrescine (Put), and content in uncommon PAs there, such as homospermidine and cadaverine, while no significant differences in free spermidine (Spd) and spermine (Spm) contents were detected. By contrast, an abscission-induced decrease was noted in the contents of insoluble conjugated Put, Spd and Spm. The maximum activity of PAO coincided with the maximum content of Spd and Spm, and it was localized mainly in parenchyma cells of pith, while DAO was present mainly in parenchyma cells of pith and cortex as well as at the base of the vascular tissue. These results suggest a clear correlation between the PA distribution and mature fruit abscission. The regulation of PA metabolism is discussed in relation to mature fruit abscission.

Tissue-specific expression of olive S-adenosyl methionine decarboxylase and spermidine synthase genes and polyamine metabolism during flower opening and early fruit development.

Polyamines (PAs) are required for cell growth and cell division in eukaryotic and prokaryotic organisms. The present study is aimed at understanding the developmental regulation of PA biosynthesis and catabolism during flower opening and early fruit development in relation to fruit size and shape. Two full-length cDNA clones coding for S-adenosyl methionine decarboxylase (SAMDC) and spermidine synthase (SPDS) homologs, key steps in the PA biosynthesis pathway, in the stone-fruit of olive (Olea europaea L.) were identified and the spatial and temporal organization of these genes were described. In olive flowers, OeSAMDC gene transcripts were highly expressed in ovary wall, placenta and ovules, while OeSPDS transcript was confined to the ovules of ovary at anthesis stage. A correlation was detected between the SAMDC enzyme activity/accumulation transcript and spermidine (Spd) and spermine (Spm) levels during flower opening, implying that the synthesis of decarboxylated SAM might be a rate-limiting step in Spd and Spm biosynthesis. OeSAMDC and OeSPDS transcripts were co-expressed in fruit mesocarp and exocarp at all developmental stages analyzed as well as in nucellus, integuments and inner epidermis tissues of fertilized ovules. In contrast, the OeSAMDC and OeSPDS genes had different expression patterns during early fruit development. The results provide novel data about localization of PA biosynthesis gene transcripts, indicating that transcript levels of PA biosynthesis genes are all highly regulated in a developmental and tissue-specific manner. The differences between the two olive cultivars in the fruit size in relation to the differences in the accumulation patterns of PAs are discussed.

Aguas cada vez más turbias

El informe originado en la Universidad de Belgrano, afirma que los efectos de la polución de los cursos hídricos son cada vez más alarmantes, especialmente en lo relativo a la contaminación industrial

Aguas cada vez más turbias

El informe originado en la Universidad de Belgrano, afirma que los efectos de la polución de los cursos hídricos son cada vez más alarmantes, especialmente en lo relativo a la contaminación industrial