570 research outputs found

    The Role of networked robotic systems to survey coastal phenomena: the Douro river plume case study

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    Propagation of river plumes along the coast strongly depends on several physical processes, which determine the plume fate over the shelf. The Douro is one of the largest rivers of the Iberian Peninsula, representing the most important freshwater input into the Atlantic Ocean on the northwestern Portuguese coast. Traditional methods of in situ measurements are often complicated and expensive due to the high spatial and temporal variability of its dominant drivers. By now, the general dispersion patterns of the Douro River Plume was mostly studied by numerical models and remote sensing imagery, considering the main drivers involved: river discharge, wind, and tide. From those results, the Douro River plume is classified as large-scale and surface-advected, presenting characteristics of a prototypical plume. The wind was found to play an essential role in the plume dispersion and fate. For example, southerly winds increase the velocity of the northward current, frequently merging the Douro plume with the northerly generated Minho plume. Both riverine water masses can propagate to the Rias Baixas (Spain), dramatically changing their normal circulation. By these reasons, the development of accurate and reliable plume monitoring systems is an important and challenging task. This work reports the recent use of robotic systems (AUVs and UAVs) to detect, track and survey the Douro Plume front autonomously. These systems can survey this highly dynamic environment and characterize the frontal regions of the plume regarding salinity, water temperature, turbidity, and chlorophyll concentrations under summer conditions when the plume area is small and mainly tidally driven. Results from several frontal crossings, coincident with satellite imagery acquisitions (some of which were obtained in near real-time by the new Sentinel-2 mission), demonstrated the AUVs capability to fairly detect the front structure. Cross-frontal exchanges observed in the water column by AUVs along the front emphasize the importance of new technologies use on the monitoring and detection of high spatial and temporal dynamical phenomena such as river plumes.Peer Reviewe

    Scaling Behavior of Transverse Kinetic Energy Distributions in Au+Au Collisions at sNN=200\sqrt{s_{\rm NN}}=200 GeV

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    With the experimental data from STAR on the centrality dependence of transverse momentum pTp_T spectra of pions and protons in Au+Au collisions at sNN=200GeV\sqrt{s_{NN}}=200 {\rm GeV}, we investigate the scaling properties of transverse energy ETE_T distributions at different centralities. In the framework of cluster formation and decay mechanism for particle production, the universal transverse energy distributions for pion and proton can be described separately but not simultaneously.Comment: 5 pages, 5 eps figures included, to be appeared in Nucl. Phys.

    Synthesis of dietetic structures lipids from spent coffee grounds crude oil catalyzed by commercial immobilized lipases and immobilized Rhizopus oryzae lipase on biochar and hybrid support

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    The aim of this study was the valorization of coffee industry residues, namely spent coffee grounds (SCG) as a source of oil, and silverskin (CS) as a source of both oil and biomass, under the concept of the circular economy. Therefore, crude oil from SCG was used to produce low-calorie structured lipids (SL) for food and pharmaceutical industries, and CS to produce biochar by pyrolysis for biotechnological uses. SL were obtained by acidolysis with caprylic or capric acid, or interesterification with ethyl caprylate or ethyl caprate, in solvent-free media, catalyzed by immobilized sn-1,3 regioselective lipases. Silverskin biochar (BIO) was directly used as enzyme carrier or to produce hybrid organic-silica (HB) supports for enzyme immobilization. Rhizopus oryzae lipase (ROL) immobilized on Amberlite (AMB), silica (SIL), BIO or HB, and the commercial immobilized Thermomyces lanuginosus (Lipozyme TL IM) and Rhizomucor miehei (Lipozyme RM IM) lipases were tested. Lipozyme RM IM showed better results in SL production than Lipozyme TLIM or ROL on BIO, SIL or HB. About 90% triacylglycerol conversion was attained after 7 h acidolysis or interesterification. Lipozyme RM IM was more stable in interesterification (80% and 65% activity with ethyl caprylate or ethyl caprate) than in acidolysis (first-order decay) after 10 reusesinfo:eu-repo/semantics/publishedVersio

    Defective apoptosis in intestinal and mesenteric adipose tissue of crohn's disease patients

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    Background: Crohn's disease (CD) is associated with complex pathogenic pathways involving defects in apoptosis mechanisms. Recently, mesenteric adipose tissue (MAT) has been associated with CD ethiopathology, since adipose thickening is detected close to the affected intestinal area. However, the potential role of altered apoptosis in MAT of CD has not been addressed. Aims: To evaluate apoptosis in the intestinal mucosa and MAT of patients with CD. Methods: Samples of intestinal mucosa and MAT from patients with ileocecal CD and from non-inflammatory bowel diseases patients (controls) were studied. Apoptosis was assessed by TUNEL assay and correlated with the adipocytes histological morphometric analysis. The transcriptional and protein analysis of selected genes and proteins related to apoptosis were determined. Results: TUNEL assay showed fewer apoptotic cells in CD, when compared to the control groups, both in the intestinal mucosa and in MAT. In addition, the number of apoptotic cells (TUNEL) correlated significantly with the area and perimeter of the adipose cells in MAT. Transcriptomic and proteomic analysis reveal a significantly lower transcript and protein levels of Bax in the intestinal mucosa of CD, compared to the controls; low protein levels of Bax were found localized in the lamina propria and not in the epithelium of this tissue. Furthermore, higher level of Bcl-2 and low level of Caspase 3 were seen in the MAT of CD patients. Conclusion: The defective apoptosis in MAT may explain the singular morphological characteristics of this tissue in CD, which may be implicated in the pathophysiology of the disease. Ā© 2014 Dias et al.Crohn's disease (CD) is associated with complex pathogenic pathways involving defects in apoptosis mechanisms. Recently, mesenteric adipose tissue (MAT) has been associated with CD ethiopathology, since adipose thickening is detected close to the affected intestinal area. However, the potential role of altered apoptosis in MAT of CD has not been addressed. Aims: To evaluate apoptosis in the intestinal mucosa and MAT of patients with CD. Methods: Samples of intestinal mucosa and MAT from patients with ileocecal CD and from non-inflammatory bowel diseases patients (controls) were studied. Apoptosis was assessed by TUNEL assay and correlated with the adipocytes histological morphometric analysis. The transcriptional and protein analysis of selected genes and proteins related to apoptosis were determined. Results: TUNEL assay showed fewer apoptotic cells in CD, when compared to the control groups, both in the intestinal mucosa and in MAT. In addition, the number of apoptotic cells (TUNEL) correlated significantly with the area and perimeter of the adipose cells in MAT. Transcriptomic and proteomic analysis reveal a significantly lower transcript and protein levels of Bax in the intestinal mucosa of CD, compared to the controls; low protein levels of Bax were found localized in the lamina propria and not in the epithelium of this tissue. Furthermore, higher level of Bcl-2 and low level of Caspase 3 were seen in the MAT of CD patients. Conclusion: The defective apoptosis in MAT may explain the singular morphological characteristics of this tissue in CD, which may be implicated in the pathophysiology of the disease96e9854

    The powerful in vitro bioactivity of Euterpe oleracea Mart. seeds and related phenolic compounds

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    The Euterpe oleracea Mart. (aƧaĆ­) is a plant from the Amazon region, classified as "super fruit" because of its various functional properties. However, limited investigation has been performed on aƧaĆ­ by-products, such as seeds. Therefore, the aim of this work was to characterized the phenolic compounds of the aqueous extract of aƧaĆ­ seeds and further evaluate its bioactivity (antioxidant and cytotoxic activities. Only proanthocyanidins were detected, being a B-type (epi)catechin tetramer the most abundant; however, procyanidin trimmers were the most predominant form. AƧaĆ­ seeds extract revealed a high antioxidant (EC50 ranging from 3.6 to 19.4 Ī¼g/mL) and cytotoxic activity, being more effective in the cervical carcinoma cell line (HeLa; GI50 = 18 Ī¼g/mL); it did not show toxicity for non-tumor cells. AƧaĆ­ seeds are considered a waste and could have an added economic benefit, through the extraction of natural antioxidants, particularly proanthocyanidins, that could find applications in food and pharmaceutical industries.The authors are grateful to Foundation for Science and Technology (FCT, Portugal) for financial support to the research centre CIMO (strategic project PEst OE/AGR/UI0690/2011) and L. Barros researcher contract under ā€œPrograma Compromisso com CiĆŖncia - 2008ā€. The authors are also grateful to Jamil S. Oliveira by the initial discussions on the preparation of samples
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