Microbial food web components, bulk metabolism, and single-cell physiology of piconeuston in surface microlayers of high-altitude lakes

12 páginas, 4 tablas, 3 figuras.Sharp boundaries in the physical environment are usually associated with abrupt shifts in organism abundance, activity ,and diversity. Aquatic surface microlayers (SML) from a steep gradient between two contrasted environments, the atmosphere and surface waters, where they regulate the gas exchange between both environments. They usually harbor an abundant and active microbial life: the neuston. Few ecosystems are subjected to such a high UVR regime as high altitude lakes during summer. Here, we measured bulk estimates of heterotrophic activity, community structure and single-cell physiological properties by flow cytometry in 19 high-altitude remote Pyrenean lakes and compared the biological processes in the SML with those in the underlying surface waters. Phototrophic picoplankton (PPP) populations, were generally present in high abundances and in those lakes containing PPP populations with phycoerythrin (PE), total PPP abundance was higher at the SML .Heterotrophic nanoflagellates (HNF) were also more abundant in the SML. Bacteria in the SML had lower leucine incorporation rates, lower percentages of “live” cells, and higher numbers of highly-respiring cells ,likely resulting in a lower growth efficiency. No simple and direct linea rrelationships could be found between microbial abundances or activities and environmental variables, but factor analysis revealed that, despite their physical proximity ,microbial life in SML and underlyingwaters was governed by different and independent processes. Overall, we demonstrate that piconeuston in high altitude lakes has specific features different from those of the picoplankton ,and that they are highly affected by potential stressful environmental factors, such as high UVR radiation.This work was supported by grants 2009SGR/1177 “Grup d’estructura i funcio de xarxes tròfiques microbianes planctòniques” and 2009SGR/361 “Grup d’Ecologia dels Canvis Ambientals, GECA” from Generalitat de Catalunya, AERBAC-2 178/2010 (to EOC) and EGALA 124/2010 (MF, LC) from the Ministerio de Medio Ambiente- Red de Parques Nacionales, and PIRENA CGL2009-13318 (EOC) and NITROPIR CGL2010-19373 (MF, LC) from MINECO. HS’s work was supported by CNPq and FAPESP (Process: 2014/ 14139-3).Peer reviewe

Acoustic evaluation of modular greenery noise barriers

Green noise barriers have become an alternative means of reducing urban traffic noise. In this paper, the acoustic performance of a modular greenery noise barrier is evaluated. In situ measurements of noise reflection were performed using an experimental prototype to estimate the sound absorption coefficients. These coefficients were found to have values of approximately 0.7, higher than those previously found in laboratory measurements for a similar system with a lower vegetation density. The obtained values were input into software for predicting environmental noise to analyse the expected performance of such barriers, particularly in the case of a pair of parallel barriers. A comparison with the results for reflective barriers indicates a significant improvement in sound attenuation of up to 4 dBA. The values are similar and even superior to results reported by other authors regarding the effectiveness of absorptive treatments applied to parallel barriers, and furthermore, the proposed barriers offer an aesthetic element for environmental integration.Peer ReviewedPostprint (published version

Retinol binding Protein-4 circulating levels were higher in nonalcoholic fatty liver disease vs. histologically normal liver from morbidly obese women.

We aimed to analyze the retinol binding protein-4 (RBP4) messenger RNA (mRNA) expression profiles in adipose tissues and liver of morbidly obese (MO) women with or without nonalcoholic fatty liver disease (NAFLD), and to study the relationships with other pro- and anti-inflammatory adipokines in vivo and in vitro. We performed a cross-sectional analysis of subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT) and liver samples from four lean and 45 MO women with or without NAFLD by enzyme-linked immunosorbent assay and real-time reverse transcription-PCR. We also studied RBP4 expression in HepG2 hepatocytes under various inflammatory stimuli. Circulating RBP4 levels were higher in MO women, and specifically, in MO subjects with NAFLD compared with normal liver controls (lean and MO). RBP4 liver expression was higher in nonalcoholic steatohepatitis (NASH)-moderate/severe than in NASHmild. Overall RBP4 gene expression was higher in liver than in adipose tissues. Among them, the higher expression corresponded to SAT. VAT expression was lower in the MO cohort. In HepG2, RBP4 mRNA expression was reduced by tumor necrosis factor (TNF)-α and increased by adiponectin treatment. In conclusion, the results obtained in MO women with NAFLD, brings up the use of RBP4 and other adipokines as a panel of noninvasive molecular biomarkers when NAFLD is suspected. Further studies are needed with other obesity groups.Fil: Terra, Ximena. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; EspañaFil: Auguet, Teresa. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; España. Hospital Universitari Joan XXIII. Servei Medicina Interna,; EspañaFil: Broch, Montserrat. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; EspañaFil: Sabench, Fátima. Hospital Sant Joan de Reus. Servei de Cirurgia,; EspañaFil: Hernandez, Mercè. Hospital Sant Joan de Reus. Servei de Cirurgia,; EspañaFil: Pastor, Rosa M.. Hospital Universitari Joan XXIII. Laboratori de Bioquímica; EspañaFil: Quesada, Isabel María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentina. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; EspañaFil: Lunna, Ana. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; EspañaFil: Aguilar, Carmen. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; EspañaFil: Del Castillo, Daniel. Hospital Sant Joan de Reus. Servei de Cirurgia, ; EspañaFil: Richard, Cristobal. Universitat Rovira i Virgil. Departament de Medicina i Cirurgia; España. Hospital Universitari Joan XXIII. Servei Medicina Interna,; Españ

Ordering kinetics evaluation of FeAl powders

In this study, time resolved X-ray diffraction experiments using synchrotron X-ray radiation have been performed to get insight on the time and temperature dependent atomic ordering of an intermetallic Fe-40A1 (at.%) ball-milled powder. The target of the present study is to gain knowledge on the rapid heating processes occurring during Thermal Spray coating processes. Present results show that in the temperature range 400 degrees C - 550 degrees C, the evolution of the order can be followed and modelled by fitting the powder diffraction patterns collected within the first minutes after fast heating. Reasonable refinements have been obtained by assuming the presence of two domains corresponding to the ordered and disordered lattices. The lattice constant changes from 0.29165 nm in the ball-milled powder at room temperature to 0.29281 nm in the ordered phase after 3000 s at 550 degrees C. The growth of the ordered phase is proposed to be a vacancy-related process with an activation energy of 1.04 eV. Above 550 degrees C, the ordering kinetics appears too fast to be resolved using the few seconds time scale of the present experiments which is in agreement to thermal spray results conditions

Assessment of Chemical Inhibitor Addition to Improve the Gas Production from Biowaste

The coexistence of sulphate-reducing bacteria and methanogenic archaea in the reactors during the anaerobic digestion from sulphate-containing waste could favor the accumulation of sulfide on the biogas, and therefore reduce its quality. In this study, the effect of sulphate-reducing bacteria inhibitor (MoO−2 4 ) addition in a two phase system from sulphate-containing municipal solid waste to improve the quality of the biogas has been investigated. The results showed that although SRB and sulphide production decreased, the use of inhibitor was not effective to improve the anaerobic digestion in a two phase system from sulphate-containing waste, since a significant decrease on biogas and organic matter removal were observed. Before MoO−2 4 addition the average values of volatile solid were around 12 g/kg, after 5 days of inhibitor use, those values did exceed to 28 g/kg. Molybdate caused acidification in the reactor and it was according to decrease in the pH values. In relation to microbial consortia, the effect of inhibitor was a decrease in Bacteria (44%; 60% in sulphate-reducing bacteria) and Archaea (38%) population

Pharmacogenetics of efficacy and safety of HCV treatment in HCV-HIV coinfected patients: significant associations with IL28B and SOCS3 gene variants.

Background and Aims This was a safety and efficacy pharmacogenetic study of a previously performed randomized trial which compared the effectiveness of treatment of hepatitis C virus infection with pegylated interferon alpha (pegIFNα) 2a vs. 2b, both with ribavirin, for 48 weeks, in HCV-HIV coinfected patients. Methods The study groups were made of 99 patients (efficacy pharmacogenetic substudy) and of 114 patients (safety pharmacogenetic substudy). Polymorphisms in the following candidate genes IL28B, IL6, IL10, TNFα, IFNγ, CCL5, MxA, OAS1, SOCS3, CTLA4 and ITPA were assessed. Genotyping was carried out using Sequenom iPLEX-Gold, a single-base extension polymerase chain reaction. Efficacy end-points assessed were: rapid, early and sustained virological response (RVR, EVR and SVR, respectively). Safety end-points assessed were: anemia, neutropenia, thrombocytopenia, flu-like syndrome, gastrointestinal disturbances and depression. Chi square test, Student's T test, Mann-Whitney U test and logistic regression were used for statistic analyses. Results As efficacy is concerned, IL28B and CTLA4 gene polymorphisms were associated with RVR (p<0.05 for both comparisons). Nevertheless, only polymorphism in the IL28B gene was associated with SVR (p = 0.004). In the multivariate analysis, the only gene independently associated with SVR was IL28B (OR 2.61, 95%CI 1.2-5.6, p = 0.01). With respect to safety, there were no significant associations between flu-like syndrome or depression and the genetic variants studied. Gastrointestinal disturbances were associated with ITPA gene polymorphism (p = 0.04). Anemia was associated with OAS1 and CTLA4 gene polymorphisms (p = 0.049 and p = 0.045, respectively), neutropenia and thromobocytopenia were associated with SOCS3 gene polymorphism (p = 0.02 and p = 0.002, respectively). In the multivariate analysis, the associations of the SOCS3 gene polymorphism with neutropenia (OR 0.26, 95%CI 0.09-0.75, p = 0.01) and thrombocytopenia (OR 0.07, 95%CI 0.008-0.57, p = 0.01) remained significant. Conclusions In HCV-HIV coinfected patients treated with PegIFNα and ribavirin, SVR is associated with IL28B rs8099917 polymorphism. HCV treatment-induced neutropenia and thrombocytopenia are associated with SOCS3 rs4969170 polymorphism

Microbial food web components, bulk metabolism, and single-cell physiology of piconeuston in surface microlayers of high-altitude lakes

Sharp boundaries in the physical environment are usually associated with abrupt shifts in organism abundance, activity, and diversity. Aquatic surface microlayers (SML) form a steep gradient between two contrasted environments, the atmosphere and surface waters, where they regulate the gas exchange between both environments. They usually harbor an abundant and active microbial life: the neuston. Few ecosystems are subjected to such a high UVR regime as high altitude lakes during summer. Here, we measured bulk estimates of heterotrophic activity, community structure and single-cell physiological properties by flow cytometry in 19 high-altitude remote Pyrenean lakes and compared the biological processes in the SML with those in the underlying surface waters. Phototrophic picoplankton (PPP) populations, were generally present in high abundances and in those lakes containing PPP populations with phycoerythrin (PE), total PPP abundance was higher at the SML. Heterotrophic nanoflagellates (HNF) were also more abundant in the SML. Bacteria in the SML had lower leucine incorporation rates, lower percentages of "live" cells, and higher numbers of highly-respiring cells, likely resulting in a lower growth efficiency. No simple and direct linear relationships could be found between microbial abundances or activities and environmental variables, but factor analysis revealed that, despite their physical proximity, microbial life in SML and underlying waters was governed by different and independent processes. Overall, we demonstrate that piconeuston in high altitude lakes has specific features different from those of the picoplankton, and that they are highly affected by potential stressful environmental factors, such as high UVR radiation

Differential scanning calorimetry and elasticity of textured, heat set and mechanical strained polylactide multifilaments

Industrially textured PLA multifilaments were heat set under different conditions at 110 ºC for 1 min and subjected to one cycle of deformation up to 20%. Thermal transitions of the original textured, heat set and cyclic strained filaments were measured using differential scanning calorimetry from 25 to 250 ºC. Cyclic deformation induces an endo-exo transition at peak temperatures between 55 - 60 ºC that is not observed in the original textured and heat set multifilaments. There is another endo-exo transition with peak temperatures between 67 and 72 ºC in all filaments, the intensity of which varies according to texturing conditions, heat setting and cycle strain. Texturing conditions, heat setting and cyclic strain play a role in thermal transitions, the strain at breaking and elastic properties of the filaments. The crystallinity and magnitude of the endo-exo thermal events detected by DSC are related to the strain at breaking and elasticity of polylactide textured multifilamentsPostprint (published version

Skin microbiome of coral reef fish is highly variable and driven by host phylogeny and diet

Background The surface of marine animals is covered by abundant and diversified microbial communities, which have major roles for the health of their host. While such microbiomes have been deeply examined in marine invertebrates such as corals and sponges, the microbiomes living on marine vertebrates have received less attention. Specifically, the diversity of these microbiomes, their variability among species, and their drivers are still mostly unknown, especially among the fish species living on coral reefs that contribute to key ecosystem services while they are increasingly affected by human activities. Here, we investigated these knowledge gaps analyzing the skin microbiome of 138 fish individuals belonging to 44 coral reef fish species living in the same area. Results Prokaryotic communities living on the skin of coral reef fishes are highly diverse, with on average more than 600 OTUs per fish, and differ from planktonic microbes. Skin microbiomes varied between fish individual and species, and interspecific differences were slightly coupled to the phylogenetic affiliation of the host and its ecological traits. Conclusions These results highlight that coral reef biodiversity is greater than previously appreciated, since the high diversity of macro-organisms supports a highly diversified microbial community. This suggest that beyond the loss of coral reefs-associated macroscopic species, anthropic activities on coral reefs could also lead to a loss of still unexplored host-associated microbial diversity, which urgently needs to be assessed