63 research outputs found

    Degradation of widespread cyanotoxins with high impact in drinking water (microcystins, cylindrospermopsin, anatoxin-a and saxitoxin) by CWPO

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    This Accepted Manuscript will be available for reuse under a CC BY-NC-ND license after 24 months of embargo periodThe occurrence of harmful cyanobacterial blooms has unabated increased over the last few decades, posing a significant risk for public health. In this work, we investigate the feasibility of catalytic wet peroxide oxidation (CWPO) promoted by modified natural magnetite (Fe3O4-R400/H2O2), as an inexpensive, simple-operation and environmentally-friendly process for the removal of the cyanotoxins that show the major impact on drinking water: microcystins (MC-LR and MC-RR), cylindrospermopsin (CYN), anatoxin-a (ATX) and saxitoxin (STX). The performance of the system was evaluated under ambient conditions and circumneutral pH (pH0 = 5) using relevant cyanotoxin concentrations (100–500 μg L−1). The nature of the cyanotoxins determined their reactivity towards CWPO, which decreased in the following order: MC-RR > CYN > MC-LR ≫ ATX > STX. In this sense, microcystins and CYN were completely removed in short reaction times (1–1.5 h) with a low catalyst concentration (0.2 g L−1) and the stoichiometric amount of H2O2 (2–2.6 mg L−1), while only 60–80% conversion was achieved with ATX and STX in 5 h. In these cases, an intensification of the operating conditions (1 g L−1 catalyst and up to 30 mg H2O2 L−1) was required to remove both toxins in 1 h. The impact of the main components of freshwaters i.e. natural organic matter (NOM) and several inorganic ions (HCO3−, HPO42-, SO42-) on the performance of the process was also investigated. Although the former led to a partial inhibition of the reaction due to HO· scavenging and catalyst coating, the latter did not show any remarkably effect, and the versatility of the process was finally confirmed in a real surface water. To further demonstrate the effectiveness of the catalytic system, the toxicity of both the initial cyanotoxins and the resulting CWPO effluents was measured with the brine shrimp Artemia salina. Remarkably, all CWPO effluents were non-toxic at the end of the treatment.This research has been supported by the Spanish MINECO through the project CTM-2016-76454-R and by the CM through the project P2018/EMT-4341. M. Munoz thanks the Spanish MINECO for the Ramón y Cajal postdoctoral contract (RYC-2016-20648). J. Nieto-Sandoval thanks the Spanish MINECO for the FPI predoctoral grant (BES-2017-081346

    Photo-Fenton oxidation of cylindrospermopsin at neutral pH with LEDs

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    Cylindrospermopsin (CYN) is a potent cyanobacterial toxin found in freshwaters worldwide. In this work, the feasibility of the photo-Fenton process under neutral pH using light emitting diodes as irradiation source for the removal of this hazardous cyanotoxin from freshwater was investigated. The impact of the kind of iron chelating agent (ethylenediamine-N, N′-disuccinic acid vs. ethylenedinitrilotetraacetic acid) as well as the effect of the main operating conditions viz. H2O2 dose, Fe(III) load, initial CYN concentration, and Fe(III):EDDS molar ratio on the performance of the process was systematically evaluated. EDDS was selected as the most appropriate iron chelating agent considering the kinetics of the process and the environmental impact (Vibrio fischeri and Artemia salina). Under optimized conditions ([H2O2] = 30 mg L−1; [Fe(III)] = 5 mg L−1; Fe(III):ligand = 1:0.5 (molar ratio)), complete removal of CYN was achieved in 15-min reaction time. Furthermore, the catalytic system showed to be effective in real water matrices (river and reservoir waters) spiked with CYN. Although the presence of inorganic ions (mainly HCO3−/CO32−) and dissolved organic carbon decreased the oxidation rate of CYN due to scavenging reactions and iron coordination, respectively, complete elimination of the cyanotoxin was achieved in all cases. The fate of EDDS along the process was also evaluated to demonstrate that the catalytic system investigated, apart from its effectiveness, warrants the complete absence of residues after reaction. Therefore, the proposed system constitutes a promising method for cyanotoxin treatment either as a drinking water treatment step in conventional plants or as a potential remediation strategy in the natural environmentOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research has been supported by the CYTED Ibero-American Science and Technology Program for Development (CYTED-2019) through the project TALGENTOX (PCI2020-112013) and by the Spanish Ministry for Science and Innovation (MICINN) through the project PID2019-105079RB-I00. D. Ortiz has received a FPU predoctoral grant (FPU19/04816) from the Spanish Ministry of Universities. M. Munoz has received a Ramón y Cajal postdoctoral contract (RYC-2016–20648) from the Spanish MINEC

    Monolithic stirrer reactors for the sustainable production of dihydroxybenzenes over 3D printed Fe/γ-Al2O3 monoliths: kinetic modeling and CFD simulation

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    The aim of this work is to evaluate the performance of the stirring 3D Fe/Al2O3 monolithic reactor in batch operation applied to the liquid-phase hydroxylation of phenol by hydrogen peroxide (H2O2 ). An experimental and numerical investigation was carried out at the following operating conditions: CPHENOL,0 = 0.33 M, CH2O2,0 = 0.33 M, T = 75–95◦C, P = 1 atm, ω = 200–500 rpm and WCAT ~ 1.1 g. The kinetic model described the consumption of the H2O2 by a zero-order power-law equation, while the phenol hydroxylation and catechol and hydroquinone production by Eley–Rideal model; the rate determining step was the reaction between the adsorbed H2O2, phenol in solution with two active sites involved. The 3D CFD model, coupling the conservation of mass, momentum and species together with the reaction kinetic equations, was experimentally validated. It demonstrated a laminar flow characterized by the presence of an annular zone located inside and surrounding the monoliths (u = 40–80 mm s−1 ) and a central vortex with very low velocities (u = 3.5–8 mm s−1 ). The simulation study showed the increasing phenol selectivity to dihydroxybenzenes by the reaction temperature, while the initial H2O2 concentration mainly affects the phenol conversio

    Influence of the aqueous matrix on the degradation of cyanotoxins by CWPO: a study on the Iberian Peninsula freshwaters

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    The increasing occurrence of toxic cyanobacterial blooms worldwide represents a critical health and environmental risk. Catalytic wet peroxide oxidation (CWPO) has emerged as an efficient and environmentally friendly technology for the removal of cyanotoxins in water. Nevertheless, its effectiveness has just been demonstrated in deionized water or simple synthetic aqueous matrices. In this work, the effect of the different components of the aqueous matrix on the CWPO of cyanotoxins was deeply evaluated considering the widespread properties of the Iberian Peninsula freshwaters. The presence of Cl-, HCO3- and SO42- ions reduced the oxidation rate of cylindrospermopsin (CYN) up to 70–80% at the highest concentrations tested (2000, 250 and 500 mg L−1 for Cl-, HCO3- and SO42-, respectively) due to their hydroxyl radical scavenging capacity. The presence of natural organic matter (NOM) resulted in a similar outcome (oxidation rate reduction up to 90% at the highest concentration tested, 20 mg L−1), but in this case due to the consumption of hydroxyl radicals in competition with CYN oxidation. The presence of NO3- and H2PO4- did not show any significant effect on CYN oxidation. Similarly, the presence of cyanobacteria (Chrysosporum ovalisporum, 50 µg chlorophyll-a L−1) did not appreciably affect the CYN oxidation rate. These results were consistent with those obtained by evaluating the impact of real aqueous matrices from drinking water treatment plants (DWTPs) located in Castilla y León and Extremadura regions (Spain) on CWPO performance. This knowledge is key to the implementation of the technology for the treatment of surface waters affected by toxic cyanobacterial bloomsThis research has been supported by the CYTED Ibero-American Science and Technology Program for Development (CYTED-2019) through the project TALGENTOX (PCI2020–112013) and by Spanish Ministry for Science and Innovation (MICINN) through the project PID2019–105079RB-I00. D. Ortiz thanks the Spanish Ministry of Universities (MIU) for the FPU predoctoral grant (FPU19/04816). M. Munoz thanks the Spanish MINECO for the Ramon ´ y Cajal postdoctoral contract (RYC-2016–20648). We especially thank Aqualia for providing the water samples from DWTPs employed in this study, which was performed in the framework of Rewaise project (http://rewaise.eu

    Serum Phospholipids Fatty Acids and Breast Cancer Risk by Pathological Subtype

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    This study evaluates whether serum phospholipids fatty acids (PL-FAs) and markers of their endogenous metabolism are associated with breast cancer (BC) subtypes. EpiGEICAM is a Spanish multicenter matched case-control study. A lifestyle and food frequency questionnaire was completed by 1017 BC cases and healthy women pairs. Serum PL-FA percentages were measured by gas chromatography-mass spectrometry. Conditional and multinomial logistic regression models were used to quantify the association of PL-FA tertiles with BC risk, overall and by pathological subtype (luminal, HER2+ and triple negative). Stratified analyses by body mass index and menopausal status were also performed. Serum PL-FAs were measured in 795 (78%) pairs. Women with high serum levels of stearic acid (odds ratio (OR)T3vsT1 = 0.44; 95% confidence interval (CI) = 0.30-0.66), linoleic acid (ORT3vsT1 = 0.66; 95% CI = 0.49-0.90) and arachidonic to dihomo-γ-linolenic acid ratio (OR T3vsT1 = 0.64; 95% CI = 0.48-0.84) presented lower BC risk. Participants with high concentrations of palmitoleic acid (ORT3vsT1 = 1.65; 95% CI = 1.20-2.26), trans-ruminant palmitelaidic acid (ORT3vsT1 = 1.51; 95% CI = 1.12-2.02), trans-industrial elaidic acid (ORT3vsT1 = 1.52; 95% CI = 1.14-2.03), and high oleic to stearic acid ratio (ORT3vsT1 = 2.04; 95% CI = 1.45-2.87) showed higher risk. These associations were similar in all BC pathological subtypes. Our results emphasize the importance of analyzing fatty acids individually, as well as the desaturase activity indices

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

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    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

    Rising rural body-mass index is the main driver of the global obesity epidemic in adults

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    Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

    Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

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    © The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups

    Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

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    Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics

    Actualidad y prospectiva de la investigación científica en el Centro Universitario Amecameca de la Universidad Autónoma del Estado de México

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    Con responsabilidad, se organizó un programa cuya finalidad fuera publicitar con transparencia dichos avances, a través de un esfuerzo de rendición de cuentas a la comunidad inmediata, la universitaria, y a la comunidad abierta, la sociedad que la principal referencia para tal efecto. El programa se concretiza a través del presente libro, conformado con una inspiración de investigación multidisciplinaria; sin embargo, para llegar a tal fin, el reto es realizar el proceso de búsqueda y generación de conocimiento transitando hacia la colaboración de los cuerpos académicos, que puedan construir nuevos conocimientos fortalecidos por la convergencia de diferentes campos del saber. En consecuencia, la primera etapa de esta estrategia es la publicidad de los trabajos investigativos ejercidos, para hacer un balance al día, pero también proyectar el futuro de cada campo y área del conocimiento. La organización explicativa está organizada por tres bloques representativos del quehacer en la generación de conocimiento del Centro Universitario, un primer bloque centra el interés en las humanidades, educación y sustentabilidad; el segundo bloque lo integra la reflexión científica sobre la construcción democrática, derechos humanos y equidad de género; en el tercer segmento se destina a la seguridad alimentaria, salud pública y sistemas agropecuarios. La actualidad de la investigación eleva la producción lograda y lo que en el momento se encuentra en construcción y los alcances que produce para la docencia, la investigación misma, y para la sociedad en general. La prospectiva es un área que todos los capítulos desarrollan con el propósito de delinear los alcances innovadores por andar en teoría, metodología e incluso en los saberes mismo
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