Fenton reactions were applied to the degradation of dissolved organic matter (OM) and fouling removal of iron oxide membranes. Humic acid (HA), bovine serum albumin (BSA) and sodium alginate (SA), ...were used as models of humic substances, proteins and polysaccharides respectively. The degradation reaction was performed with H2O2 1mM at pH of 2.5 and the reactant concentration was measured over time by total organic carbon (TOC) and HPLC. Dissolved and particulate iron were efficient catalyst, achieving mineralization rates of 80%, 40% and 85% for HA, BSA and SA respectively. The H2O2 solution was applied as a cleaning agent on membranes previously fouled by the compounds individually, as well as their mixtures. Hydraulic cleaning of the membrane surfaces did not show significant improvement; Fenton treatment produced a flow recovery of 97% for HA, 86% for BSA and 88% for SA. Flux recovery was slightly lower for mixtures, where chemical interactions between foulants yielded a more compact, recalcitrant layer. Membrane surfaces were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM), showing residual foulants after treatment, regardless of the flux recovery achieved. The results showed the cleaning ability of this reagent with a very good recovery of the initial flux.
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•An iron oxide ultrafiltration ceramic membrane was fabricated.•Fenton reaction was used as membrane cleaning strategy.•Batch experiments were performed with iron oxide nanoparticles and organic matter.•Iron oxide membranes were effective catalyst in Fenton reaction with organic matter.•Membrane cleaning was effective for successive fouling-cleaning cycles.
Introduction
Serum levels of procalcitonin and C‐reactive protein (CRP) have been used to predict anastomotic leakage after colorectal surgery, but information is scarce in advanced ovarian cancer ...(AOC) surgery with bowel resection. This study aimed to assess the predictive value of procalcitonin and CRP in detecting anastomotic leakage after AOC surgery with bowel resection. The study also aimed to determine the optimal postoperative reference values and the best day for evaluating these markers.
Material and methods
This prospective, observational and multicentric trial included 92 patients with AOC undergoing debulking surgery with bowel resection between 2017 and 2020 in 10 reference hospitals in Spain. Procalcitonin and CRP levels were measured at baseline and on postoperative days 1–6. Receiver operating characteristic analysis was performed to evaluate the predictive value of procalcitonin and CRP at each postoperative day. Sensitivity, specificity, positive and negative predictive values were calculated.
Results
Anastomotic leakage was detected in six patients (6.5%). Procalcitonin and CRP values were consistently higher in patients with anastomotic leakage at all postoperative days. The maximum area under the curve (AUC) for procalcitonin was observed at postoperative day 1 (AUC = 0.823) with a cutoff value of 3.8 ng/mL (83.3% sensitivity, 81.3% specificity). For CRP, the maximum AUC was found at postoperative day 3 (AUC = 0.833) with a cutoff level of 30.5 mg/dL (100% sensitivity, 80.4% specificity).
Conclusions
Procalcitonin and C‐reactive protein are potential biomarkers for early detection of anastomotic leakage after ovarian cancer surgery with bowel resection. Further prospective studies with a larger sample size are needed to confirm these findings.
This trial involving women undergoing ovarian cancer surgery with bowel resection aimed to predict the risk of anastomotic leakage using serum inflammatory markers. Levels of procalcitonin and C‐reactive protein were consistently higher in patients with anastomotic leakage (AL) throughout the early postoperative period.
Molecular imprinted polymers are custom made materials with specific recognition sites for a target molecule. Their specificity and the variety of materials and physical shapes in which they can be ...fabricated make them ideal components for sensing platforms. Despite their excellent properties, MIP-based sensors have rarely left the academic laboratory environment. This work presents a comprehensive review of recent reports in the environmental and biomedical fields, with a focus on electrochemical and optical signaling mechanisms. The discussion aims to identify knowledge gaps that hinder the translation of MIP-based technology from research laboratories to commercialization.
In recent years, the current media ecosystem has been transformed owing to the adaptation to digital media, affecting all genres and audiovisual formats. As a result, from the point of view of ...participation, the viewer-user has acquired an unprecedented protagonism owing to the possibility now offered by social networks. The informative genre, far from turning its back on this reality, has allied itself with it and is exploring new ways of reaching audiences, and one of the latest trends has to do with informative television channels and the use of Instagram reels. This research focuses on the case of RTVE Noticias (@rtvenoticias), with the purpose of analyzing the use and communication strategy that they make of Instagram reels on this platform, precisely because it is the feature that has achieved more popularity of late. The findings show that RTVE Noticias does not currently have a clear strategy when it comes to informing through this medium, which translates into content being reused from other media without really taking advantage of the narrative potential of the network, resulting in low interaction with followers. The main results obtained allow us to continue a rich academic debate related to the media’s use of social networks from the perspective of information and consumption, mainly among the youngest users.
Porous alumina has been shown to be an excellent adsorbent for Congo Red (CR) dye. In this work, highly porous g-Al2O3 nanoshells were synthesized from alumina coated carbon black (CB) obtained from ...a new deposition technique and used for removal of CR dye from aqueous solutions. Adsorption experiments were conducted in a batch mode and a series of parameters were investigated, including contact time, initial dye concentrations, ionic strength and pH of the solutions. It was found that equilibrium for CR adsorption can be reached within 30 min, much faster than reported by other studies in the literature on similar adsorbents. It was also found that the adsorption capacity of Al2O3 nanoshells is 44.8 % higher than that of alumina/CB. The adsorption capacity of Al2O3 nanoshells was more favorable at lower pH, and the optimal adsorption ability was achieved at pH 4.0 with a removal efficiency at 98.6 %. The Al2O3 nanoshells have a maximum adsorption capacity of 370.4 mg g−1 (25 °C; pH 7; no salt added), better than or comparable to those reported in the literature. A pseudo-second-order kinetics model can best fit the kinetics of CR adsorption, which follows the Langmuir isotherm. The high adsorption capacity is attributed to the strong hydrogen-bonding interactions between the anionic dye and Al2O3 nanoshells surface as well as to the electrostatic interactions between CR dye and the Al2O3 nanoshells.
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•Highly porous γ-alumina nanoshells made from a new coating technique as adsorbent.•High adsorption capacity of 370.4 mg g−1 achieved for removal Congo red from water.•Fast adsorption equilibrium reached in less than 30 min.•Adsorption kinetics of Congo red on the porous alumina follows Langmuir isotherm.
Photonic crystals (PCs) are nanomaterials with photonic properties made up of periodically modulated dielectric materials that reflect light between a wavelength range located in the photonic band ...gap. Colloidal PCs (C-PC) have been proposed for several applications such as optical platforms for the formation of physical, chemical, and biological sensors based on a chromatic response to an external stimulus. In this work, a robust protocol for the elaboration of photonic crystals based on SiO2 particle (SP) deposition using the vertical lifting method was studied. A wide range of lifting speeds and particle suspension concentrations were investigated by evaluating the C-PC reflectance spectrum. Thinner and higher reflectance peaks were obtained with a decrease in the lifting speed and an increase in the SP concentrations up to certain values. Seven batches of twelve C-PCs employing a SP 3% suspension and a lifting speed of 0.28 µm/s were prepared to test the reproducibility of this method. Every C-PC fabricated in this assay has a wavelength peak in a range of 10 nm and a peak width lower than 90 nm. Inverse-opal polymeric films with a highly porous and interconnected morphology were obtained using the developed C-PC as a template. Overall, these results showed that reproducible colloidal crystals could be elaborated on a large scale with a simple apparatus in a short period, providing a step forward in the scale-up of the fabrication of photonic colloidal crystal and IO structures as those employed for the elaboration of photonic polymeric sensors.
The Photo-Fenton-like (PF-like) process with minute Fe(III) concentrations and the Hydrogen Peroxide Photolysis (HPP), using Xe-lamp or solar light as sources of irradiation, were efficiently applied ...to eliminate the herbicide 2,4-D from water.
PF-like experiments concerning ferric and H2O2 concentrations of 0.6 mg L−1 and 20 mg L−1 respectively, using Xenon lamps (Xe-lamps) as a source of irradiation and 2,4-D concentrations of 10 mg L−1 at pH 3.6, exhibited complete 2,4-D degradation and 77% dissolved organic carbon (DOC) removal after 30 min and 6 h of irradiation respectively whereas HPP (in absence of ferric ions) experiments showed a 2,4-D reduction and DOC removal of 90% and 7% respectively after 6 h of irradiation. At pH 7.0, HPP process achieved a 2,4-D abatement of approximately 75% and a DOC removal of 4% after 6 h. PF-like exhibited slightly improved 2,4-D and DOC removals (80% and 12% respectively) after the same irradiation time probably due to the low pH reduction (from 7.0 to 5.6). Several chlorinated-aromatic intermediates were identified by HPLC-MS. These by-products were efficiently removed by PF at pH 3.6, whereas at neutral PF-like and acid or neutral HPP, they were not efficiently degraded. With natural solar light irradiation, 10 and 1 mg L−1 of 2,4-D were abated using minor H2O2 concentrations (3, 6, 10 and 20 mg L−1) and iron at 0.6 mg L−1 in Milli-Q water. Similar results to Xe-lamp experiments were obtained, where solar UV-B + A light H2O2 photolysis (HPSP) and solar photo-Fenton-like (SPF-like) played an important role and even at low H2O2 and ferric concentrations of 3 and 0.6 mg L−1 respectively, 2,4-D was efficiently removed at pH 3.6. Simulated surface water at pH 3.6 containing 1 mg L−1 2,4-D, 20 mg L−1 H2O2 and 0.6 mg L−1 Fe(III) under natural sunlight irradiation efficiently removed the herbicide and its main metabolite 2,4-DCP after 30 min of treatment while at neutral pH, 40% of herbicide degradation was achieved. In the case of very low iron concentrations (0.05 mg L−1) at acid pH, 150 min of solar treatment was required to remove 2,4-D.
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•Photo-Fenton processes at low iron concentrations achieved 2,4-D degradation.•UV-B H2O2 photolysis was also able to degrade the herbicide 2,4-D at pH 7 and 3.6•Photo-Fenton process was more effective at acid pH values.•Chlorinated-aromatic metabolites were found during photo-induced processes.•UV-B H2O2 photolysis and neutral photo-Fenton led to the low 2,4-D removal.
Introduction: The use of virtual reality and 360-degree video technologies in the field of journalism has led to the emergence of new lines of research, like the one addressed in this article. ...Objectives: This study focuses on the exploration of the different issues related to the production of pieces of the so-called immersive journalism and examines how the narrative elements of traditional journalism are reformulated in these immersive pieces. Methods: The study is based on the analysis of 2,178 pieces of immersive journalism produced by Spanish and international media companies, between 2012 and 2017. Results and conclusions: This analysis has allowed us to develop an innovative proposal for the classification of immersive journalism genres, which has not been done before. This typology is based on the analysis of the reformulation of the narrative elements of news storytelling within immersive journalism. Keywords Immersive journalism; virtual reality; 360-degree video; genres; immersion; immersive genres.
•Small viruses’ removal by ultrafiltration depends on aqueous matrix composition.•Salts in the aqueous matrix affect ultrafiltration, leading to partial virus removal.•Ca2+ and Mg2+ reduce the ...ultrafiltration effectiveness as opposed to Na+ and HCO3−.•Virus rejection by ultrafiltration is correlated with electrostatic interactions.•DLVO and XDLVO predicted the observed PP7 stability and PP7-membrane interactions.
Ultrafiltration membranes are increasingly used in potabilization to remove viral particles. This removal is controlled by electrostatic repulsion, attachment and size exclusion. The effect of electrostatic interaction in virus filtration was investigated. Our work included characterization of bacteriophage PP7 and polyethersulfone membrane with respect to size and surface charge; the removal of this bacteriophage at laboratory scale by ultrafiltration membrane process and the mechanism and limitations were analyzed and discussed under DLVO and XDLVO theories. A partial removal of the bacteriophage was achieved; however, enhanced separation may be achieved considering that the process is affected by the aqueous matrix. The presence of divalent cations diminished the effectiveness of the procedure as opposed to monovalent cations and species with amphoteric behavior such as bicarbonate. DLVO and XDLVO predicted the interactions studied between bacteriophage PP7 and polyethersulfone membrane.
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