2,220 research outputs found

    Seasonal rather than spatial variability drives planktonic and benthic bacterial diversity in a microtidal lagoon and the adjacent open sea

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    Coastal lagoons are highly productive ecosystems, which are experiencing a variety of human disturbances at increasing frequency. Bacteria are key ecological players within lagoons, yet little is known about the magnitude, patterns and drivers of diversity in these transitional environments. We carried out a seasonal study in the Venice Lagoon (Italy) and the adjacent sea, to simultaneously explore diversity patterns in different domains (pelagic, benthic) and their spatio-temporal variability, and test the role of environmental gradients in structuring assemblages. Community composition differed between lagoon and open sea, and between domains. The dominant phyla varied temporally, with varying trends for the two domains, suggesting different environmental constraints on the assemblages. The percentage of freshwater taxa within the lagoon increased during higher river run-off, pointing at the lagoon as a dynamic mosaic of microbial taxa that generate the metacommunity across the whole hydrological continuum. Seasonality was more important than spatial variability in shaping assemblages. Network analyses indicated more interactions between several genera and environmental variables in the open sea than the lagoon. Our study provides evidences for a temporally dynamic nature of bacterial assemblages in lagoons and suggests that an interplay of seasonally influenced environmental drivers shape assemblages in these vulnerable ecosystems

    Lossy mode resonance enabling ultra-low detection limit for fibre-optic biosensors (INVITED)

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    The combination of optical fibre-based biosensors with nanotechnologies is providing the opportunity for the development of in situ, portable, lightweight, versatile and high-sensitivity optical sensing platforms. We report on the generation of lossy mode resonances (LMRs) by means of the deposition of nm-thick SnO2 film on optical fibres. This allows measuring precisely and accurately the changes in refractive index of the fibre-surrounding medium with very high sensitivity compared to other optical technology platforms, such as long period grating or surface plasmon resonance. This approach, mixed with the use of specialty fiber structures such as Dshaped fibres, allows improving the light-matter interaction in strong way. Different imaging systems, i.e. SEM and TEM along with X-EDS tool, have been used to study the optical features of the fiber coating. The shift of the LMR has been monitored in real-time thanks to conventional wavelength interrogation system and ad hoc developed microfluidics. A big leap in performance has been attained by detecting femtomolar concentrations in human serum. The biosensor reusability has been also tested by using a solution of sodium dodecyl sulphate.This work was supported by the National Research Council of Italy (CNR) for the Short Term Mobility program 2017, by the Government of Navarra (project no. 72/2015) and by the Spanish Agencia Estatal de Investigacion (AEI) and European Regional Development Fund (FEDER) (TEC2016-78047-R,TEC2016-79367-C2-2-R)

    Serum protein levels following surgery in breast cancer patients: A protein microarray approach

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    Este artículo ha sido publicado en INTERNATIONAL JOURNAL OF ONCOLOGY No hemos podido encontrar infomración sobre si permite depositar conlicencia creative Commons El archivo solicitado a la editorial como postprint que nos ha remitido es el que depositamosSurgery is the primary treatment for non-metastatic breast cancer. However, the risk of early recurrence remains after surgical removal of the primary tumor. Recurrence is suggested to result from hidden micrometastatic foci, which are triggered to escape from dormancy by surgical resection of the primary tumor. In this study, we focused on the differential impact of breast surgery on the serum profiles of early breast cancer patients and healthy women. Serum samples from invasive breast cancer patients, in situ carcinoma breast cancer patients and healthy women were analyzed using reverse phase protein array technology. Samples were collected prior to breast surgery and 24 h following breast surgery. Both the expression level and the velocity of 42 serum proteins were quantified and compared among groups. We found that surgery increased the concentration of several proteins (CSF1, THSB2, IL6, IL7, IL16, FasL and VEGF-B) in the overall population. Compared with healthy women and patients with non-invasive tumors, invasive tumor patients exhibited higher preoperative levels of several serum proteins, such as αFP, IFNβ1, VEGF-A, IL18, E-cadherin or CD31, and lower postoperative levels of TNFα and IL5. Similarly, we detected significant surgery-induced changes in the velocity of VEGF-A and IL16 accumulation in samples derived from invasive breast cancer patients. In conclusion, breast surgery induced distinct changes in the concentrations and dynamics of serum proteins in invasive breast cancer patients compared with healthy women and noninvasive tumor patients.The authors acknowledge support through grants from the Junta de Andalucia (0199/2006 and TIC-4026), the Fundacion Mutua Madrileña and the Spanish MINECO (TIN2010-16556)

    Reciclado de escorias de fondo de central térmica para su uso como áridos en la elaboración de componentes prefabricados de hormigón

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    The need to eliminate waste generates costs. When considering the preservation of the environment, the minimization of the consumption of natural resources and energy savings criteria, the need and advisability of studying the feasibility of waste re-use seems clear. However, waste re-use depends on whether they are economically competitive. Therefore, the aim of this study is to evaluate the possible use of slag from a steam power station as aggregate in the manufacture of concrete. This study included the determination of the physical, chemical and thermal properties of the material, comparing the results to those required by the Spanish structural concrete code (EHE) in determining their acceptance or rejection as a concrete component. The ultimate aim of the research was to determine the highest slag content that could be added to concrete without modifying its strength or durability, with a view to obtaining savings in the manufacture of precast structures.La necesidad de eliminar residuos genera gastos. Considerando criterios de conservación ambiental, minimización del consumo de recursos naturales y ahorro de energía parece claro la necesidad y conveniencia de estudiar la viabilidad del uso de residuos. Sin embargo la utilización de residuos depende de que sean competitivos económicamente. Por tanto el propósito de esta investigación es evaluar el posible uso de las escorias de fondo de una central térmica como áridos para la fabricación de hormigón. En este estudio se incluye la determinación de características físicas, químicas y térmicas y se han comparado los resultados a los requeridos por la EHE para determinar su aceptación o rechazo como componente de un hormigón. El objetivo final de la investigación responde a la utilización de hormigón con el máximo contenido en escorias sin modificar las condiciones de resistencia y durabilidad, consiguiendo un ahorro económico en la fabricación de estructuras prefabricadas

    Intra-islet insulin synthesis defects are associated with endoplasmic reticulum stress and loss of beta cell identity in human diabetes

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    Aims/hypothesis: Endoplasmic reticulum (ER) stress and beta cell dedifferentiation both play leading roles in impaired insulin secretion in overt type 2 diabetes. Whether and how these factors are related in the natural history of the disease remains, however, unclear. Methods: In this study, we analysed pancreas biopsies from a cohort of metabolically characterised living donors to identify defects in in situ insulin synthesis and intra-islet expression of ER stress and beta cell phenotype markers. Results: We provide evidence that in situ altered insulin processing is closely connected to in vivo worsening of beta cell function. Further, activation of ER stress genes reflects the alteration of insulin processing in situ. Using a combination of 17 different markers, we characterised individual pancreatic islets from normal glucose tolerant, impaired glucose tolerant and type 2 diabetic participants and reconstructed disease progression. Conclusions/interpretation: Our study suggests that increased beta cell workload is accompanied by a progressive increase in ER stress with defects in insulin synthesis and loss of beta cell identity. Graphical abstract: [Figure not available: see fulltext.

    Non-linear effects of drought under shade: reconciling physiological and ecological models in plant communities

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    The combined effects of shade and drought on plant performance and the implications for species interactions are highly debated in plant ecology. Empirical evidence for positive and negative effects of shade on the performance of plants under dry conditions supports two contrasting theoretical models about the role of shade under dry conditions: the trade-off and the facilitation hypotheses. We performed a meta-analysis of field and greenhouse studies evaluating the effects of drought at two or more irradiance levels on nine response variables describing plant physiological condition, growth, and survival. We explored differences in plant response across plant functional types, ecosystem types and methodological approaches. The data were best fit using quadratic models indicating a humped-back shape response to drought along an irradiance gradient for survival, whole plant biomass, maximum photosynthetic capacity, stomatal conductance and maximal photochemical efficiency. Drought effects were ameliorated at intermediate irradiance, becoming more severe at higher or lower light levels. This general pattern was maintained when controlling for potential variations in the strength of the drought treatment among light levels. Our quantitative meta-analysis indicates that dense shade ameliorates drought especially among drought-intolerant and shade-tolerant species. Wet tropical species showed larger negative effects of drought with increasing irradiance than semiarid and cold temperate species. Non-linear responses to irradiance were stronger under field conditions than under controlled greenhouse conditions. Non-linear responses to drought along the irradiance gradient reconciliate opposing views in plant ecology, indicating that facilitation is more likely within certain range of environmental conditions, fading under deep shade, especially for drought-tolerant species
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