Some findings on the spatial and temporal distribution of methane emissions in landfills

The purpose of this article is to present some facts of interest for the quantification of gas emissions in active landfills obtained from a series of field campaigns in a case study landfill where spatial and temporal patterns of methane emissions were analyzed. Nine campaigns were carried out to measure diffuse surface methane emissions at an European municipal waste landfill in operation using the static flow chamber technique in different seasons over three years. Results obtained show a global annual diffuse flux of 733.26 t CH4/year for the year 2020. Certain points on the surface, where concentrations reached values above 1000 ppm, were observed during the campaigns. These points, called "hotspots", represented only 10% of all the points measured but accounted for 73% of the total diffuse methane emissions (506 t CH4/year). Furthermore, localized emissions, such as those from landfill gas extraction wells, which were not connected to the general extraction network, were also analyzed. These localized emissions represent more than twice the total diffuse emissions measured on the surface (1500 t CH4/year). These results highlight the importance of identifying high emission points to design effective mitigation measures. Moreover, the influence of certain meteorological conditions such as atmospheric pressure, temperature or rainfall was also studied. A new particular effect has been detected regarding precipitation, which favors or hinders methane emissions depending on the volume accumulated during the previous weeks. Pressure was found to be the factor that most affects methane emission variations in the case studied, presenting a clear inverse correlation with the field data that was collected. This suggests the need to consider the meteorological fluctuations over time to calculate the field emission estimates. Correcting the annual estimation in the case studied by considering the atmospheric pressure fluctuations over the year led to a 14% change in the estimate, obtaining a final result of 836.73 t CH4/year for the total diffuse emissions

Periodic venting of MABR lumen allows high removal rates and high gas-transfer efficiencies

The membrane-aerated biofilm reactor (MABR) is a novel treatment technology that employs gas-supplying membranes to deliver oxygen directly to a biofilm growing on the membrane surface. When operated with closed-end membranes, the MABR provides 100-percent oxygen transfer efficiencies (OTE), resulting in significant energy savings. However, closed-end MABRs are more sensitive to back-diffusion of inert gases, such as nitrogen. Back-diffusion reduces the average oxygen transfer rates (OTR), consequently decreasing the average contaminant removal fluxes (J). We hypothesized that venting the membrane lumen periodically would increase the OTR and J. Using an experimental flow cell and mathematical modeling, we showed that back-diffusion gas profiles developed over relatively long timescales. Thus, very short ventings could re-establish uniform gas profiles for relatively long time periods. Using modeling, we systematically explored the effect of the venting interval (time between ventings). At moderate venting intervals, opening the membrane for 20 s every 30 min, the venting significantly increased the average OTR and J without substantially impacting the OTEs. When the interval was short enough, in this case shorter than 20 min, the OTR was actually higher than for continuous open-end operation. Our results show that periodic venting is a promising strategy to combine the advantages of open-end and closed end operation, maximizing both the OTR and OTE.Primary funding for this work was from Water Environment Research Foundation (WERF) project U2R14. Additional funding was provided by the Basque Government, partially financing Patricia Pérez, and the Spanish Ministry of Economics and Competitiveness and the European Regional Development Fund (FEDER), project “Innovative Integrated Biological Processes for Nutrients Removal (PBi2)” (CTM2012-36227)

Evaluating the behaviour of the new MSW reject fraction landfills: HD-Vertere Project

El proyecto HD-Vertere (Hidrología y Degradación de VERTEderos de REchazos), tiene como objetivo conocer cómo son los procesos hidrológicos y de degradación bio-química en los nuevos vertederos europeos, como base fundamental para optimizar su gestión. Está siendo desarrollado desde 2013 por investigadores de la Universidad de Cantabria, con la colaboración de la Consejería de Medio Ambiente del Gobierno de Cantabria, a traves de la empresa pública MARE.HD-Vertere (Hydrology and Degradation in Rejections Landfills) Project aims to determine the hydrological and bio-chemical degradation processes that take place in the new european landfills as a basis for optimizing their management. It is being carried out since 2013 by researchers from the University of Cantabria (Spain), in collaboration with the environmental agency of the Cantabria Government, through the public company MARE.This work is funded by the Spanish Ministry of Economics and Competitiveness through the CTM2012-35055 project. The project is financed jointly by the European Regional Development Fund, FEDER (operational period 2007-2013)

Cost-Effectiveness Analysis of Sewer Mining versus Centralized Wastewater Treatment: Case Study of Arga River Basin (Spain)

ABSTRACT:In the context of the EU Water Framework Directive, a Cost-Effectiveness Analysis (CEA) was performed to compare centralized and decentralized wastewater treatment strategies aimed to improve the ecological status of a Spanish river. The implementation of several hybrid membrane bioreactors within the urban framework for sewer mining (SM) was compared with the more common wastewater treatment plant enlargement option. The assessment ranked 6 alternatives based on 12 potential scenarios, aimed at narrowing the uncertainty of the CEA. The cost analysis illustrated that SM is the most expensive option regarding both investment and operation and maintenance costs. However, the effectiveness of the alternatives evaluated depends significantly on the scenarios considered, being SM the most effective in most cases. Finally, the cost-effectiveness ratio showed SM as the best cost-effective alternative. CEA provides an ecological-economic indicator useful to prioritize wastewater treatment alternatives to achieve a given objective

Reactor biológico anóxico-anaerobio para la eliminación de nutrientes de aguas residuales.

Reactor biológico para eliminación de nutrientes de aguas residuales caracterizado por estar compartimentado verticalmente en tres zonas, Anóxica, Anaerobia y de Clarificación, que cumplen las funciones de eliminación biológica de materia orgánica y fósforo, desnitrificación y decantación. Flujo de agua residual ascendente al producirse la entrada en la zona inferior Anaerobia, y salida en la zona superior de Clarificación. Se ha de instalar precediendo a otro proceso aerobio para nitrificación y afino de materia orgánica cuyo efluente se recircula para producir las condiciones anóxicas. Dispone de sistemas de mezcla y agitación de las zonas Anaerobia y Anóxica, y recirculación de sólidos entre ambas. Se reducen y simplifican las instalaciones necesarias para tratamiento de aguas residuales con eliminación de nutrientes. No se produce consumo de reactivos. Se optimiza el aprovechamiento de la materia orgánica del agua residual. Se obtiene un efluente con baja carga contaminante.Solicitud: 201000058 (12.01.2010)Nº Pub. de Solicitud: ES2338979A1 (13.05.2010)Nº de Patente: ES2338979B2 (23.09.2010

LA PRÁCTICA ALIMENTARIA Y LOS DETERMINANTES SOCIALES EN NIÑOS MEXICANOS DE 6 A 12 AÑOS

Introducción: Los determinantes sociales influyen en la cantidad, variedad, calidad y tipo de alimentos disponibles y accesibles. Las prácticas alimentarias inadecuadas van en incremento, situación que puede aumentar la probabilidad de padecer enfermedades crónicas no trasmisibles. La Norma Oficial Mexicana 043 recomienda la inclusión de tres grupos de alimentos en los tres principales tiempos de comida. Objetivo: Determinar si la práctica alimentaria está asociada a los determinantes sociales en niños mexicanos de 6 a 12 años. Métodos y procedimientos: Estudio longitudinal, se analizaron a 101 niños a través de registros alimentarios. Se identificaron el consumo alimentario y la inclusión de los tres grupos de alimentos en cada tiempo de comida. El software utilizado fue Nutris® y NCSS8. Resultados: El 48.5% de los niños son del género masculino. La media de edad fue de 9.22 ± 1.72 (DE), años, 83.2% asistió en el horario matutino. El 57.43% de las madres trabajan. La mayoría de las madres tienen escolaridad de licenciatura. El 65.3% de las familias tienen 4 y 5 personas. El 48.5% de los niños no tuvo práctica alimentaria adecuada en el desayuno, 8.9% en el tiempo de comida y 53.4% en la cena en ninguno de los días estudiados.  Conclusiones: Existen altas proporciones de niños con práctica alimentaria inadecuada. Los que asistieron en el turno matutino tienen mejor práctica alimentaria en el tiempo de la comida. Los niños de familias compuestas por tres integrantes tuvieron mayor cantidad de días con adecuada práctica alimentaria.ABSTRACTIntroduction: The social determinants influencing the quantity, variety, quality and type of food available and accessible. Inadequate feeding practices are on the increase, a situation that can increase the likelihood of chronic non-communicable diseases. Mexican Official Standard 043 recommends the inclusion of three food groups in the three main meal times. Objective: Determine whether food practice is associated with social determinants in Mexican children from 6 to 12 years. Methods and procedures: longitudinal study, 101 children were analyzed through food records. Food consumption and the inclusion of the three food groups at each meal were identified. The software used was Nutris® and NCSS8. Results: 48.5% of children are male. The mean age was 9.22 ± 1.72 (SD) years, 83.2% he attended in the morning hours. The 57.43% of mothers work. Most mothers have undergraduate schooling. 65.3% of families are 4 and 5 people. 48.5% of children did not have adequate food practice at breakfast, 8.9% at mealtime and 53.4% at dinner in any of the days studied. Conclusions: There are high proportions of children with inadequate dietary practice. Those who attended the morning shift have better food practice at mealtime. Children from families consisting of three members had more days with adequate food practice.Palabras Clave: Determinante social, práctica alimentaria, alimentación, Social Determinant, food practice, feed.

Functional Heterogeneity of Mouse and Human Brain OPCs: Relevance for Preclinical Studies in Multiple Sclerosis.

Besides giving rise to oligodendrocytes (the only myelin-forming cell in the Central Nervous System (CNS) in physiological conditions), Oligodendrocyte Precursor Cells (OPCs) are responsible for spontaneous remyelination after a demyelinating lesion. They are present along the mouse and human CNS, both during development and in adulthood, yet how OPC physiological behavior is modified throughout life is not fully understood. The activity of adult human OPCs is still particularly unexplored. Significantly, most of the molecules involved in OPC-mediated remyelination are also involved in their development, a phenomenon that may be clinically relevant. In the present article, we have compared the intrinsic properties of OPCs isolated from the cerebral cortex of neonatal, postnatal and adult mice, as well as those recovered from neurosurgical adult human cerebral cortex tissue. By analyzing intact OPCs for the first time with 1H High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (1H HR-MAS NMR) spectroscopy, we show that these cells behave distinctly and that they have different metabolic patterns in function for their stage of maturity. Moreover, their response to Fibroblast Growth Gactor-2 (FGF-2) and anosmin-1 (two molecules that have known effects on OPC biology during development and that are overexpressed in individuals with Multiple Sclerosis (MS)) differs in relation to their developmental stage and in the function of the species. Our data reveal that the behavior of adult human and mouse OPCs differs in a very dynamic way that should be very relevant when testing drugs and for the proper design of effective pharmacological and/or cell therapies for MS.post-print753 K

Do ART and chemsex drugs get along? Potential drug-drug Interactions in a cohort of people living with HIV who engaged in chemsex: a retrospective observational study.

Introduction: People living with HIV (PLWH) who engaged in chemsex are at risk of potential drug-drug interactions (pDDIs) with recreational drugs. This study aimed to characterize pDDIs between antiretroviral treatment (ART) and chemsex drugs and evaluate their association with unscheduled relevant hospital consultations. Methods: We conducted a single-center, retrospective, observational study in a series of gay, bisexual, and other men who have sex with men (gbMSM) living with HIV who engaged in chemsex and who attended a tertiary hospital in Barcelona, Spain, from February 2018 through August 2019. Associations between all recorded pDDIs and relevant unscheduled consultations were estimated using the incidence rate (IR) per 100 person-years of those events compared between patients with no pDDI (green flag) or moderate severity pDDI (orange flag) with patients with high severity pDDI (red flag) using the incidence rate ratio (IRR). Results: Among 172 PLWH engaged in chemsex, 249 ART regimens were prescribed: 44% based on integrase inhibitors, 30% on boosted ART, and 26% based on non-nucleoside reverse transcriptase inhibitors. The substances and recreational drugs most frequently used were erectile dysfunction agents (83%), methamphetamine (79%), GHB (77%), and alkyl nitrites (71%). Polydrug use was reported in 52%. We observed 2048 pDDIs. Of these, 23% were orange flag pDDIs; 88% related to boosted ARTs. The IR of the 285 unscheduled relevant episodes in patients with orange flag pDDIs was 64.67 (95% CI 40.07-89.28). The IRR of green flag pDDIs was 1.05 (95% CI 0.60-1.8; p = 0.876). Conclusion: One in four pDDIs were of moderate severity but no significant increase in the incidence of unscheduled relevant consultations was observed. A high number of unscheduled consultations, predominantly for psychiatric events and intoxication, were observed. Beyond using non-boosted ART to minimize pDDIs, other factors related to the practice of chemsex must be addressed, in order to offer a better approach

SARS-CoV-2 mutant spectra reveal differences between COVID-19 severity categories

Trabajo presentado en el XVI Congreso Nacional de Virología, celebrado en Málaga (España) del 06 al 09 de septiembre de 2022.RNA virus populations are composed of complex mixtures of genomes that are termed mutant spectra. SARS-CoV-2 replicates as a viral quasispecies, and mutations that are detected at low frequencies in a host can be dominant in subsequent variants. We have studied mutant spectrum complexities of SARS-CoV-2 populations derived from thirty nasopharyngeal swabs of patients infected during the first wave (April 2020) in the Hospital Universitario Fundación Jiménez Díaz. The patients were classified according to the COVID-19 severity in mild (non-hospitalized), moderate (hospitalized) and exitus (hospitalized with ICU admission and who passed away due to COVID-19). Using ultra-deep sequencing technologies (MiSeq, Illumina), we have examined four amplicons of the nsp12 (polymerase)-coding region and two amplicons of the spike-coding region. Ultra-deep sequencing data were analyzed with different cut-off frequency for mutation detection. Average number of different point mutations, mutations per haplotype and several diversity indices were significantly higher in SARS-CoV-2 isolated from patients who developed mild disease. A feature that we noted in the SARS-CoV-2 mutant spectra from diagnostic samples is the remarkable absence of mutations at intermediate frequencies, and an overwhelming abundance of mutations at frequencies lower than 10%. Thus, the decrease of the cut-off frequency for mutation detection from 0.5% to 0.1% revealed an increasement (50- to 100 fold) in the number of different mutations. The significantly higher frequency of mutations in virus from patients displaying mild than moderate or severe disease was maintained with the 0.1% cut- off frequency. To evaluate whether the frequency repertoire of amino acid substitutions differed between SARS-CoV-2 and the well characterized hepatitis C virus (HCV), we performed a comparative study of mutant spectra from infected patients using the same bioinformatics pipelines. HCV did not show the deficit of intermediate frequency substitutions that was observed with SARS-CoV-2. This difference was maintained when two functionally equivalent proteins, the corresponding viral polymerases, were compared. In conclusion, SARS-CoV-2 mutant spectra are rich reservoirs of mutants, whose complexity is not uniform among clinical isolates. Virus from patients who developed mild disease may be a source of new variants that may acquire epidemiological relevance.This work was supported by Instituto de Salud Carlos III, Spanish Ministry of Science and In-novation (COVID-19 Research Call COV20/00181), and co-financed by European Development Regional Fund ‘A way to achieve Europe’. The work was also supported by grants CSIC-COV19-014 from Consejo Superior de Investigaciones Científicas (CSIC), project 525/C/2021 from Fundació La Marató de TV3, PID2020-113888RB-I00 from Ministerio de Ciencia e Innovación, BFU2017-91384-EXP from Ministerio de Ciencia, Innovación y Universidades (MCIU), PI18/00210 and PI21/00139 from Instituto de Salud Carlos III, and S2018/BAA-4370 (PLATESA2 from Comunidad de Madrid/FEDER). C.P., M.C., and P.M. are supported by the Miguel Servet programme of the Instituto de Salud Carlos III (CPII19/00001, CPII17/00006, and CP16/00116, respectively) co-financed by the European Regional Development Fund (ERDF). CIBERehd (Centro de Investi-gación en Red de Enfermedades Hepáticas y Digestivas) is funded by Instituto de Salud Carlos III. Institutional grants from the Fundación Ramón Areces and Banco Santander to the CBMSO are also acknowledged. The team at CBMSO belongs to the Global Virus Network (GVN). B.M.-G. is supported by predoctoral contract PFIS FI19/00119 from Instituto de Salud Carlos III (Ministerio de Sanidad y Consumo) cofinanced by Fondo Social Europeo (FSE). R.L.-V. is supported by predoctoral contract PEJD-2019-PRE/BMD-16414 from Comunidad de Madrid. C.G.-C. is sup-ported by predoctoral contract PRE2018-083422 from MCIU. BS was supported by a predoctoral research fellowship (Doctorados Industriales, DI-17-09134) from Spanish MINECO