2,064 research outputs found
An innovative, fast and facile soft-template approach for the fabrication of porous PDMS for oil-water separation
Oil wastewater and spilled oil caused serious environmental pollution and
damage to public health in the last years. Therefore, considerable efforts are
made to develop sorbent materials able to separate oil from water with high
selectivity and sorption capacity. However most of them are low reusable, with
low volume absorption capacity and poor mechanical properties. Moreover, the
synthesis is time-consuming, complex and expensive limiting its practical
application in case of emergency. Here we propose an innovative approach for
the fabrication of porous PDMS starting from an inverse water-in-silicone
procedure able to selectively collect oil from water in few seconds. The
synthesis is dramatically faster than previous approaches, permitting the
fabrication of the material in few minutes independently from the dimension of
the sponges. The porous material evidenced a higher volume sorption capacity
with respect to other materials already proposed for oil sorption from water
and excellent mechanical and reusability properties.This innovative fast and
simple approach can be successful in case of emergency, as oil spill accidents,
permitting in situ fabrication of porous absorbents
On the key role of droughts in the dynamics of summer fires in Mediterranean Europe
Summer fires frequently rage across Mediterranean Europe, often intensified by high temperatures and droughts. According to the state-of-the-art regional fire risk projections, in forthcoming decades climate effects are expected to become stronger and possibly overcome fire prevention efforts. However, significant uncertainties exist and the direct effect of climate change in regulating fuel moisture (e.g. warmer conditions increasing fuel dryness) could be counterbalanced by the indirect effects on fuel structure (e.g. warmer conditions limiting fuel amount), affecting the transition between climate-driven and fuel-limited fire regimes as temperatures increase. Here we analyse and model the impact of coincident drought and antecedent wet conditions (proxy for the climatic factor influencing total fuel and fine fuel structure) on the summer Burned Area (BA) across all eco-regions in Mediterranean Europe. This approach allows BA to be linked to the key drivers of fire in the region. We show a statistically significant relationship between fire and same-summer droughts in most regions, while antecedent climate conditions play a relatively minor role, except in few specific eco-regions. The presented models for individual eco-regions provide insights on the impacts of climate variability on BA, and appear to be promising for developing a seasonal forecast system supporting fire management strategies.We thank the European Forest Fire Information System-EFFIS (http://effis.jrc.ec.europa.eu) of the European
Commission Joint Research Centre for the fire data. We acknowledge the SPEI data providers (http://sac.csic.
es/spei/database.html). Special thanks to Joaquín Bedia, Esteve Canyameras, Xavier Castro and Andrej Ceglar
for helpful discussions on the study. This work was partially funded by the Project of Interest “NextData” of the Italian Ministry for Education, University and Research and by the EU H2020 Project 641762 “ECOPOTENTIAL: Improving Future Ecosystem Benefits through Earth Observations”. Ricardo Trigo was supported by IMDROFLOOD funded by Portuguese FCT (WaterJPI/0004/2014).Peer ReviewedPostprint (published version
Trajetória da pesquisa cafeeira no Brasil - 1932 a 2012.
A mensuração dos impactos das inovações tecnológicas é relevante para a revisão das diretrizes dos programas das Instituições de Pesquisa e Desenvolvimento, bem como para as Instituições relacionadas à assistência técnica e extensão rural. Para avaliar os impactos das inovações, sejam ambientais ou socioeconômicos, é necessário estudar a evolução da pesquisa e identificar as tecnologias que resultaram em pontos de ruptura para o desenvolvimento setorial. Tendo em vista a relevância histórica do setor cafeeiro para a economia brasileira, este estudo identificou as tecnologias que representaram pontos de ruptura no desenvolvimento da cafeicultura nacional, delineou a trajetória da pesquisa com o café no Brasil, no período 1932 a 2012, e identificou regionalmente a evolução do emprego das tecnologias desenvolvidas para o setor
Evidence for the Existence of an Effective Interfacial Tension between Miscible Fluids: Isobutyric Acid-Water and 1-Butanol-Water in a Spinning-Drop Tensiometer
We report definitive evidence for an effective interfacial tension between two types of miscible fluids using spinning-drop tensiometry (SDT). Isobutyric acid (IBA) and water have an upper critical solution temperature (UCST) of 26.3 degrees C. We created a drop of the IBA-rich phase in the water-rich phase below the UCST and then increased the temperature above it. Long after the fluids have reached thermal equilibrium, the drop persists. By plotting the inverse of the drop radius cubed (r(-3)) vs the rotation rate squared (omega(2)), we confirmed that an interfacial tension exists and estimated its value. The transition between the miscible fluids remained sharp instead of becoming more diffuse, and the drop volume decreased with time. We observed droplet breakup via the Rayleigh-Tomotika instability above the UCST when the rotation rate was decreased by 80%, again demonstrating the existence of an effective inter-facial tension. When pure IBA was injected into water above the UCST, drops formed inside the main drop even as the main drop decreased in volume with time. We also studied 1-butanol in water below the solubility limit. Effective interfacial tension values measured over time were practically constant, while the interface between the two phases remains sharp as the volume of the drop declines. The effective interfacial tension was found to be insensitive to changes in temperature and always larger than the equilibrium interfacial tension. Although these results may not apply to all miscible fluids, they clearly show that an effective interfacial tension can exist and be measured by SDT for some systems
Estimativa e espacialização da umidade relativa do ar no Estado do Piauí.
Este trabalho teve como objetivo obter uma equação de regressão a fim de se estimar a umidade relativa do ar, através da correlação dos dados existentes desse parâmetro com os elementos do balanço hídrico climático e, apresentar a distribuição espacial da umidade relativa do ar para o estado do Piauí
Produção de matéria seca do capim-aruana irrigado e adubado com diferentes doses de nitrogênio.
Zoneamento agroclimático para o cultivo da acerola no Estado da Bahia.
Com os valores médios de temperatura do ar e de precipitações mensais de 437 localidades do Estado da Bahia, efetuaram-se os balanços hídricos climáticos pelo método de "Thornthwaite & Mather (1955)" para uma capacidade de retenção de água no solo de 125 mm
Activation of NF-kappaB/Rel transcription factors in human primary peripheral blood mononuclear cells by interleukin 7.
Pathways that regulate the activation of NF-kappaB/Rel transcription factors are known to include signaling through a number of cytokine receptors. Interleukin 7 (IL-7), produced by bone marrow and other stromal cells, is a key factor for differentiation and survival in the lymphoid and other compartments. We found that human recombinant IL-7 induced NF-kappaB/Rel activation, analyzed by electrophoretic mobility shift assay (EMSA), in human peripheral blood T lymphocytes from healthy donors. Induced complexes included p65 and p50 NF-kappaB/Rel subunits. These results demonstrate for the first time that IL-7 can participate in signaling leading to NF-kappaB/Rel activation
Boceprevir is highly effective in treatment-experienced hepatitis C virus-positive genotype-1 menopausal women
AIM: To investigate the safety/efficacy of Boceprevirbased triple therapy in hepatitis C virus (HCV)-G1 menopausal women who were historic relapsers, partial-responders and null-responders. METHODS: In this single-assignment, unblinded study, we treated fifty-six menopausal women with HCV-G1, 46% F3-F4, and previous PEG-α/RBV failure (7% null, 41% non-responder, and 52% relapser) with 4 wk lead-in with PEG-IFNα2b/RBV followed by PEGIFNα2b/RBV+Boceprevir for 32 wk, with an additional 12 wk of PEG-IFN-α-2b/RBV if patients were HCV-RNA-positive by week 8. In previous null-responders, 44 wk of triple therapy was used. The primary objective of retreatment was to verify whether a sustained virological response (SVR) (HCV RNA undetectable at 24 wk of follow-up) rate of at least 20% could be obtained. The secondary objective was the evaluation of the percent of patients with negative HCV RNA at week 4 (RVR), 8 (RVR BOC), 12 (EVR), or at the end-of-treatment (ETR) that reached SVR. To assess the relationship between SVR and clinical and biochemical parameters, multiple logistic regression analysis was used. RESULTS: After lead-in, only two patients had RVR; HCV-RNA was unchanged in all but 62% who had ≤ 1 logio decrease. After Boceprevir, HCV RNA became undetectable at week 8 in 32/56 (57.1%) and at week 12 in 41/56 (73.2%). Of these, 53.8% and 52.0%, respectively, achieved SVR. Overall, SVR was obtained in 25/56 (44.6%). SVR was achieved in 55% previous relapsers vs. 41% non-responders (Ρ = 0.250), in 44% F0-F2 vs 54% F3-F4 (Ρ = 0.488), and in 11/19 (57.9%) of patients with cirrhosis. At univariate analysis for baseline predictors of SVR, only previous response to antiviral therapy (OR = 2.662, 95%CI: 0.957-6.881, Ρ= 0.043), was related with SVR. When considering "on treatment" factors, 1 log10 HCV RNA decline at week 4 (3.733, 95%CI: 1.676-12.658, Ρ= 0.034) and achievement of RVR BOC (7.347, 95%CI: 2.156-25.035, Ρ= 0.001) were significantly related with the SVR, al-though RVR BOC only (6.794, 95%CI: 1.596-21.644, Ρ = 0.010) maintained significance at multivariate logistic regression analysis. Anemia and neutropenia were managed with Erythropoietin and Filgrastim supplementation, respectively. Only six patients discontinued therapy. CONCLUSION: Boceprevir obtained high SVR response independent of previous response, RVR or baseline fibrosis or cirrhosis. RVR BOC was the only independent predictor of SVR
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