Spectral information to get beyond color in the analysis of water‑soluble varnish degradation

Spectral images were captured of paper samples varnished with two water-soluble materials: gum arabic and egg white. The samples were submitted to degradation processes that partially or totally eliminated the varnish from the substrate (water immersion and ageing). The spectral information was used to obtain average color data and to characterize the spatial and color inhomogeneity across pixels, showing that the pixel spectral data are critical for an accurate characterization of the degradation process of the varnishes. Since the varnishes typically become yellower with ageing, this study introduces two novel and simple-to-compute yellowness indices based on the spectral information, which are validated against a standard colorimetric index (ASTM-E313 2015). The potential uses of spectral information are demonstrated with several pieces of a real antique map sample by comparing the spectral information measured before and after cleaning the sample. To sum up, the main contributions of this study are the characterization of the spatial homogeneity through pixel-based spectral and color information and the proposal of spectral-based yellowing indices for two critical applications (ageing process follow-up and effect of cleaning), as demonstrated with synthetic and historical samples of varnished paper respectively.Spanish Ministry of Economy and Competitiveness, under research Grant DPI2015-64571-R. Spanish State Agency of Research (AEI) and the Ministry for Economy, Industry and Competitiveness (MIMECO) by means of the Grant Number FIS2017-89258-P with European Union FEDER (European Regional Development Funds) support

Estimación de la radiación global diaria en zonas de topografía compleja utilizando modelos digitales del terreno e imágenes de Meteosat: comparación de los resultados

Ponencia presentada en: XXIX Jornadas Científicas de la AME y el VII Encuentro Hispano Luso de Meteorología celebrado en Pamplona, del 24 al 26 de abril de 2006.El conocimiento de la radiación solar es muy importante a la hora de diseñar sistemas solares tanto térmicos, como fotovoltaicos. En escalas locales, la topografía es el factor más importante modulador de la radiación solar en superficie. En este trabajo se estima la radiación global diaria en todo tipo de condiciones de cielo, en zonas que presentan una topografía compleja. Para ello se utilizará una metodología basada en Modelos Digitales del Terreno (MDT) a partir, por un lado, de medidas piranométricas y, por otro, de imágenes de satélite. Se pone de manifiesto que la aplicación del MDT sobre medidas piranométricas proporciona mejores resultados que las estimaciones a partir de imágenes de satélite, si bien la precisión obtenida (RMSE & MBE) es del mismo orden de magnitud en ambos casos

Bacteria associated with Copestylum (Diptera, Syrphidae) larvae and their cactus host Isolatocereus dumortieri

We describe the gut bacterial diversity inhabiting two saprophagous syrphids and their breeding substrate (decayed tissues of the columnar cactus Isolatocereus dumortieri). We analyzed the gut microbiota of Copestylum latum (scooping larvae that feed on decayed cactus tissues) and Copestylum limbipenne (whose larvae can also feed on semiliquid tissues) using molecular techniques. DNA was extracted from larval guts and cactus tissues. The V1-V3 region of the 16S rRNA genes was amplified and sequenced. A total of 31079 sequences were obtained. The main findings are: C. limbipenne is dominated by several Enterobacteriaceae, including putative nitrogen-fixing genera and pectinolitic species and some denitrifying species, whereas in C. latum unclassified Gammaproteobacteria predominate. Decayed tissues have a dominant lactic acid bacterial community. The bacterial communities were more similar between larval species than between each larva and its breeding substrate. The results suggest that the gut bacterial community in these insects is not strongly affected by diet and must be dependent on other factors, such as vertical transmission, evolutionary history and host innate immunity.This research was funded by AECID (project A/020305/08), FOMIX CONACYT-Hidalgo (project 95828) and SEP-CONACYT (project 84127) to M. A. M.-G., and BFU2009-12895-C02-01 from the Ministerio de Ciencia e Inovación to A.L. A.P.M. acknowledge the scholarship provided by The Alβan programme, the European Union Programme of High Level Scholarships for Latin America, No. E07D401138MX and CONACYT program (207522) for doctoral fellowship. A.D. is recipient of a fellowship from the Instituto de Salud Carlos III, Spain

Virus-Viroid Interactions: Citrus Tristeza Virus Enhances the Accumulation of Citrus Dwarfing Viroid in Mexican Lime via Virus-Encoded Silencing Suppressors

An assay to identify interactions between Citrus Dwarfing Viroid (CDVd) and Citrus Tristeza Virus (CTV) showed that viroid titer was enhanced by the coinfecting CTV in Mexican lime but not in etrog citron. Since CTV encodes three RNA silencing suppressors (RSSs), p23, p20 and p25, an assay using transgenic Mexican limes expressing each RSS revealed that p23 and, to a lesser extent, p25 recapitulated the effect observed with coinfections of CTV and CDVd