87 research outputs found

    On the way to specificity ‐ Microbiome reflects sponge genetic cluster primarily in highly structured populations

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    Most animals, including sponges (Porifera), have species-specific microbiomes. Which genetic or environmental factors play major roles structuring the microbial community at the intraspecific level in sponges is, however, largely unknown. In this study, we tested whether geographic location or genetic structure of conspecific sponges influences their microbial assembly. For that, we used three sponge species with different rates of gene flow, and collected samples along their entire distribution range (two from the Mediterranean and one from the Southern Ocean) yielding a total of 393 samples. These three sponge species have been previously analysed by microsatellites or single nucleotide polymorphisms, and here we investigate their microbiomes by amplicon sequencing of the microbial 16S rRNA gene. The sponge Petrosia ficiformis, with highly isolated populations (low gene flow), showed a stronger influence of the host genetic distance on the microbial composition than the spatial distance. Host-specificity was therefore detected at the genotypic level, with individuals belonging to the same host genetic cluster harbouring more similar microbiomes than distant ones. On the contrary, the microbiome of Ircinia fasciculata and Dendrilla antarctica - both with weak population structure (high gene flow) - seemed influenced by location rather than by host genetic distance. Our results suggest that in sponge species with high population structure, the host genetic cluster influence the microbial community more than the geographic location

    Influence of Minor Alloying Element Additions on the Crack Susceptibility of a Nickel Based Superalloy Manufactured by LPBF

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    Inconel 738LC (IN738LC) is a nickel-based superalloy specially used in the hot section components of turbine engines. One of its main drawbacks relies on the cracking susceptibility when it is manufactured by laser powder bed fusion (LPBF). This paper analyzes the influence of minor alloying element concentration on cracking tendency of IN738LC superalloy manufactured by LPBF. For that objective, samples were manufactured using two powders, which presented different minor alloying elements concentration (Si, Zr and B). It was shown that the samples crack tendency was very different depending on the powder used for their manufacturing. In fact, the measured crack density value was 2.73 mm/mm2 for the samples manufactured with the powder with higher minor alloying elements concentration, while 0.25 mm/mm2 for the others. Additionally, a special emphasis has been put on elemental composition characterization in cracked grain boundaries in order to quantify possible Si or Zr enrichment. It has been also studied the differences of solidification ranges and grain structures between both samples as a consequence of different minor alloying elements concentration in order to analyze their effect on crack susceptibility. In this sense, Scheil-Gulliver simulation results have shown that samples with higher Si and Zr contents presented higher solidification range temperature. This fact, as well as an increase of the presence of high angle grain boundaries (HAGB), leaded to an increment in the crack formation during solidification. Therefore, in this research work, an understanding of the factors affecting crack phenomenon in the LPBF manufactured IN738LC was accomplished.This research was funded by the Elkartek Programme, Grant Number KK-2020/00042

    Characterization of Leptoglossus occidentalis eggs and egg glue

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    Producción CientíficaSimple Summary: This study explored the chemical components of the egg glue used by the Western Conifer Seed Bug (Leptoglossus occidentalis Heidemann, 1910) to agglutinate eggs and adhere to pine needles. Results showed that the adhesive secretion includes plasticizers and thermoplastic elastomer resins with semiochemical properties in an oily matrix containing proteins. This knowledge of the egg glue composition can be used to develop new control strategies for L. occidentalis, potentially limiting the economic impact caused by this pest insect that reduces the production of pine nuts by up to 25%.The western conifer seed bug (Leptoglossus occidentalis Heidemann, 1910, Heteroptera: Coreidae) has a significant economic impact due to the reduction in the quality and viability of conifer seed crops; it can feed on up to 40 different species of conifers, showing a clear predilection for Pinus pinea L. in Europe. Its incidence is especially relevant for the pine nut-producing industry, given that the action of this pest insect can reduce the production of pine nuts by up to 25%. As part of ongoing efforts aimed at the design of control strategies for this insect, this work focuses on the characterization (by scanning electron microscopy–energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, and gas chromatography–mass spectroscopy, GC–MS) of the compounds released by these insects during oviposition, with emphasis on the adhesive secretion that holds L. occidentalis eggs together. Elemental analysis pointed to the presence of significant amounts of compounds with high nitrogen content. Functional groups identified by infrared spectroscopy were compatible with the presence of chitin, scleroproteins, LNSP-like and gelatin proteins, shellac wax analogs, and policosanol. Regarding the chemical species identified by GC–MS, eggs and glue hydromethanolic extracts shared constituents such as butyl citrate, dibutyl itaconate, tributyl aconitate, oleic acid, oleamide, erucamide, and palmitic acid, while eggs also showed stearic and linoleic acid-related compounds. Knowledge of this composition may allow advances in new strategies to address the problem caused by L. occidentalis.Unión Europea, LIFE MycoRestore - (project LIFE18 CCA/ES/001110

    Strain driven migration of In during the growth of InAs/GaAs quantum posts

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    Using the mechano-optical stress sensor technique, we observe a counter-intuitive reduction of the compressive stress when InAs is deposited on GaAs (001) during the growth of quantum posts. Through modelling of the strain fields, we find that such anomalous behaviour can be related to the strain-driven detachment of In atoms from the crystal and their surface diffusion towards the self-assembled nanostructures.We acknowledge the financial support by Spanish MINECO through Grant Nos. ENE2012-37804-C02-02 and TEC2011-29120-C05-04, and by Spanish CAM through Grant Nos. S2009/ESP-1503 and S2009/ENE-1477.Peer Reviewe

    When Red Turns Black: Influence of the 79 AD Volcanic Eruption and Burial Environment on the Blackening/Darkening of Pompeian Cinnabar

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    It is widely known that the vivid hue of red cinnabar can darken or turn black. Many authors have studied this transformation, but only a few in the context of the archeological site of Pompeii. In this work, the co-occurrence of different degradation patterns associated with Pompeian cinnabar-containing fresco paintings (alone or in combination with red/yellow ocher pigments) exposed to different types of environments (pre- and post-79 AD atmosphere) is reported. Results obtained from the in situ and laboratory multianalytical methodology revealed the existence of diverse transformation products in the Pompeian cinnabar, consistent with the impact of the environment. The effect of hydrogen sulfide and sulfur dioxide emitted during the 79 AD eruption on the cinnabar transformation was also evaluated by comparing the experimental evidence found on paintings exposed and not exposed to the post-79 AD atmosphere. Our results highlight that not all the darkened areas on the Pompeian cinnabar paintings are related to the transformation of the pigment itself, as clear evidence of darkening associated with the presence of manganese and iron oxide formation (rock varnish) on fragments buried before the 79 AD eruption has also been found.The research leading to these results has received funding from “la Caixa” Foundation (Silvia Pérez-Diez, ID 100010434, Fellowship code LCF/BQ/ES18/11670017). A.P.M. is a Serra Húnter fellow. A.P.M’s research was supported by a Beatriu de Pinós postdoctoral grant (2017 BP-A 00046) of the Government of Catalonia’s Secretariat for Universities & Research of the Ministry of Economy and Knowledge. This work has been supported by the project MADyLIN (BIA2017-87063-P) funded by the Spanish Agency for Research AEI (MINECO-FEDER/UE). The authors thank for the funding provided by University of the Basque Country through the Institutionally Sponsored Open Access

    Repeatability of in-vitro optical quality measurements of intraocular lenses with a deflectometry technique effect of the toricity

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    AIM: To evaluate the repeatability of an optical device for measuring the Zernike coefficients of toric intraocular lenses (IOLs) and assess whether its toricity has any impact in its repeatability. METHODS: An experienced technician used the NIMO TR1504 to measure the Zernike coefficients 30 times for an aperture of 4.50 mm for all lenses included. The IOLs included were divided into two group: toric and non-toric ones. The cylindrical powers of the toric lenses included in the present study were 1.00, 1.50, 2.25, 3.00 and 3.75 D. Finally, the repeatability of the NIMO TR1504 was described in terms of within subject standard deviation (Sw) and repeatability limit. RESULTS: The Sw was smaller than 0.011 µm for both lens groups and all Zernike coefficients, and the difference between both groups was smaller than 0.004 µm for all Zernike coefficients. Regarding the repeatability limit, this value was smaller than 0.025 µm for the toric lens group, and smaller than 0.031 µm for the non-toric lens one for all Zernike coefficients. Furthermore, the maximum difference between both lens groups was 0.010 µm. CONCLUSION: The repeatability of the NIMO TR1504 to measure the optical quality is high and independent of the lens toricity. These results reflect that this system is robust and could be used to measure the in-vitro optical quality of either toric or non-toric IOLs

    Theoretical modelling of quaternary GaInAsSb/GaAs self-assembled quantum dots

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    Trabajo presentado al "Quantum Dot", celebrado en Nottingham (UK) del 26 al 30 de Abril de 2010.InAs/GaAs quantum dots exposed to Sb after growth exhibit spectral changes. We study in the present paper an idealized nanostructure consisting of a homogeneous distribution of the quaternary GaInAsSb surrounded by a barrier of GaAs. We nd that the valence band o set is a critical parameter in modelling its electronic structure. Depending on this value, we predict a transition from type-I to type-II band alignment at a di erent Sb concentration. The addition of Sb to reduce the transition energy while keeping a type-I alignment is only of bene t at low Sb concentrationThis work was supported by the Spanish MICINN (projects TEC2008-06756-C03-01/02/TEC, CONSOLIDER INGENIO 2010 CSD2006-0019 and CSD2009-00013), the Junta de Andalucía (PAI research groups TEP-120 and TIC-145; project P08-TEP-03516) and Comunidad Autónoma de Madrid S2009ESP-1503.Peer reviewe

    Chemometrics and elemental mapping by portable LIBS to identify the impact of volcanogenic and non-volcanogenic degradation sources on the mural paintings of Pompeii

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    Crystallization of soluble salts is a common degradation phenomenon that threatens the mural paintings of Pompeii. There are many elements that contribute to the crystallization of salts on the walls of this archaeological site. Notably, the leachates of the pyroclastic materials ejected in 79 AD by Mount Vesuvius and local groundwater, rich in ions from the erosion of volcanic rocks. Both sources could contribute to increase the concentration of halides (fluorides and chlorides) and other salts in these walls. The distribution of volcanogenic salts and their impact on the conservation of Pompeian mural paintings have however not yet been fully disclosed. In this work, an analytical methodology useful to determine the impact of the main sources of degradation affecting the mural paintings of Pompeii is presented. This methodology combines the creation of qualitative distribution maps of the halogens (CaF and CaCl) and related alkali metals (Na and K) by portable Laser Induced Breakdown Spectroscopy (LIBS) and a subsequent Principal Component Analysis of these data. Such maps, together with the in-situ identification of sulfate salts by portable Raman spectroscopy, provided information about the migration and distribution of volcanogenic halides and the influence of ions coming from additional sources (marine aerosol and modern consolidation mortars). Additionally, the thermodynamic modeling developed using the experimentally determined ionic content of Pompeian rain- and groundwater allowed to determine their specific role in the formation of soluble salts in the mural paintings of Pompeii.The research leading to these results has received funding from “la Caixa” Foundation (Silvia P erez-Diez, ID 100010434, Fellowship code LCF/BQ/ES18/11670017). This work has been supported by the Spanish Agency for Research AEI (MINECO- FEDER /UE) through the projects MADyLIN (BIA2017-87063-P) and MINECO-17-CTQ2016-77887-C2-1-R, and the Government of the Principality of Asturias (GRUPIN IDI/2018/000186). The authors thank for technical and human support provided by the laboratory Raman-LASPEA of SGIker (UPV/EHU/ ERDF, EU)

    La integración del conocimiento sobre la Cordillera Cantábrica: hacia un observatorio inter-autonómico del cambio global

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    Producción CientíficaLa Cordillera Cantábrica presenta una serie de singularidades que le convierten en un excelente enclave para el seguimiento de los efectos del cambio global. Este estudio analiza la necesidad de generar un observatorio inter-autonómico del cambio global, que permitiría integrar el conocimiento actual sobre estas montañas y determinar las prioridades en la generación de nuevo conocimiento. Para cumplir este objetivo, se presentan dos aproximaciones complementarias. La primera consiste en la revisión de la literatura científica publicada sobre la Cordillera Cantábrica y su comparación con otros enclaves geográficos de la Península Ibérica. La segunda consiste en la síntesis de información de un seminario titulado “La Cordillera Cantábrica como Centinela de los Efectos del Cambio Global”, celebrado en Santander en agosto de 2015. El análisis bibliográfico muestra que el número de publicaciones científicas sobre la Cordillera Cantábrica es similar al de otros enclaves geográficos de la Península Ibérica, pero con menor riqueza de disciplinas. La producción científica está dominada por los centros de investigación más próximos y tiene una alta participación internacional. Las conclusiones del seminario evidencian que este sistema es un candidato ideal para el seguimiento de los efectos del cambio global sobre multitud de elementos biofísicos. Se considera que la generación de un seminario permanente, junto con la consolidación de las redes de seguimiento actuales, la coordinación de nuevos trabajos, y la mejora de la comunicación entre administraciones y comunidad científico-técnica son elementos esenciales en la futura generación de un observatorio del cambio global en la Cordillera Cantábrica

    Incidence, associated factors and clinical impact of severe infections in a large, multicentric cohort of patients with systemic lupus erythematosus

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    OBJECTIVES: To estimate the incidence of severe infection and investigate the associated factors and clinical impact in a large systemic lupus erythematosus (SLE) retrospective cohort. METHODS: All patients in the Spanish Rheumatology Society Lupus Registry (RELESSER) who meet ?4 ACR-97 SLE criteria were retrospectively investigated for severe infections. Patients with and without infections were compared in terms of SLE severity, damage, comorbidities, and demographic characteristics. A multivariable Cox regression model was built to calculate hazard ratios (HRs) for the first infection. RESULTS: A total of 3658 SLE patients were included: 90% female, median age 32.9 years (DQ 9.7), and mean follow-up (months) 120.2 (±87.6). A total of 705 (19.3%) patients suffered ?1 severe infection. Total severe infections recorded in these patients numbered 1227. The incidence rate was 29.2 (95% CI: 27.6-30.9) infections per 1000 patient years. Time from first infection to second infection was significantly shorter than time from diagnosis to first infection (p < 0.000). Although respiratory infections were the most common (35.5%), bloodstream infections were the most frequent cause of mortality by infection (42.0%). In the Cox regression analysis, the following were all associated with infection: age at diagnosis (HR = 1.016, 95% CI: 1.009-1.023), Latin-American (Amerindian-Mestizo) ethnicity (HR = 2.151, 95% CI: 1.539-3.005), corticosteroids (?10mg/day) (HR = 1.271, 95% CI: 1.034-1.561), immunosuppressors (HR = 1.348, 95% CI: 1.079-1.684), hospitalization by SLE (HR = 2.567, 95% CI: 1.905-3.459), Katz severity index (HR = 1.160, 95% CI: 1.105-1.217), SLICC/ACR damage index (HR = 1.069, 95% CI: 1.031-1.108), and smoking (HR = 1.332, 95% CI: 1.121-1.583). Duration of antimalarial use (months) proved protective (HR = 0.998, 95% CI: 0.997-0.999). CONCLUSIONS: Severe infection constitutes a predictor of poor prognosis in SLE patients, is more common in Latin-Americans and is associated with age, previous infection, and smoking. Antimalarials exerted a protective effect.Spanish Foundation of Rheumatology. FIS/ISCIII (grant number PI11/02857). Dr. Pego-Reigosa is supported by Grant 316265 (BIOCAPS) from the European Union 7th Framework Programme (FP7/REGPOT-2012–2013.1)
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