Impact of the COVID-19 lockdown to a port-city area: A two-year comparative PMF analysis of PM10 of polluting sources

The objective of this study was to evaluate the effects that the COVID-19 lockdown had in the PM10 levels and sources in a city adjacent port where the transport of bulk materials is one of the main activities. For this, the 2020 PM10 chemistry and sources will be compared to an annual baseline period of 2017-18 in the same area. A total of 337 samples were chemically analyzed (30 chemical species) and a positive matrix factorization model was used to identify major PM10 sources. A Mann-Whitney test was used to find statistically relevant differences between periods. The model identified 8 factors two of them directly related to port activities (Shipping emissions and bulk materials), one associated to road traffic, three linked secondary sources (aged sea salt, secondary nitrate, ammonium sulphate) and two natural sources including fresh sea salt and long-range transport from Saharan intrusions. Road traffic and Shipping sources show a significant reduction in the lockdown period. However, after this period, the road traffic source quickly recovered showing no differences on a yearly basis with the reference year. Only the Shipping emissions source were greatly reduced in 2020 compared to 2017-18. On the other hand, the influence of natural sources kept PM10 from reducing drastically during the lockdown year (2020).This work has been carried out within the framework of the doctoral program of the University of Alicante in collaboration with companies (UAIND-17-1A). The authors want to express their gratitude to the Alicante Port Authority for their participation in this program with the project (PUERTOALICANTE1-20Y), which together with the University provided the funding the sampling and the PhD grant

Contamination, sources, and environmental hazards of groundwater in Bemetara district, Chhattisgarh, Central India

The groundwater of the the Bemetara district of Chhattisgarh in central India over a large area is hard in nature due to its high mineral content. An elevated concentration of Na+, Mg2+, Ca2+, and SO2-4 in the groundwater has been observed, falling within the ranges (n=16) 30–437, 43–341, 169–660, and 254–2,330 mg L-1 with a mean value of 107±93, 117±69, 387±171, and 1,059±595 mg L-1, respectively. The temporal and spatial variations in the groundwater concentration of species, i.e., SO2-4, Cl-, NO-3, Na+, K+, Mg2+, Ca2+, Al, and Fe, during the period 2010–2016 are described. The sources of the contaminants and quality of the groundwater are discussed. The environmental hazards of the contaminated water, i.e., land degradation, rusting of buildings and pipes, physiological drought, and ill health of aquatics, birds, and animals, in the Bemetara area are discussed

Size segregated ionic species collected in a harbour area

Water-soluble ions were analysed in size segregated aerosol samples collected in the port of Alicante (Southeastern Spain) during summer and winter using a multistage cascade impactor. Seasonal variations in the size distributions of the analysed components and the influence of bulk materials handling (loading/unloading and stockpiling) at the docks were investigated. The size distributions of SO42−, NH4+ and K+ were characterized by prominent peaks in the condensation and droplet modes, both in summer and winter, while those of Ca2+, Na+, Mg2+ and Cl− had a main peak centred at ∼4 μm. Although oxalate size distributions were similar during both seasons, the fraction of coarse-mode oxalate increased in summer most likely as a result of volatilization and repartition processes or reactions of oxalic acid with coarse alkaline particles. Nitrate size distributions were dominated by a coarse mode; however, during winter, modal peaks in the submicron size range were also observed due to favourable conditions for the formation of fine-mode NH4NO3. Harbour activities had a significant impact only on the concentrations of calcium, particularly in the coarse fraction, during both summer and winter.This work was supported by the Spanish Ministry of Science, Innovation and Universities (COSMOS Project, ref. RTI2018-098639-B-I00). The authors would also like to thank ACTRIS-Spain network (CGL2017-90884-REDT). A. Clemente thanks the Spanish Ministry of Education for a predoctoral grant (FPU18/00081)

impact of traffic flows and meteorological events on the hourly elemental composition of fine and coarse particles at an urban site

n/

Assessment of urban flood resilience in Barcelona for current and future scenarios: the RESCCUE project

The results of recent climate projections for the city of Barcelona show a relevant increment of the maximum rainfall intensities for the period 2071–2100. Considering the city as a system of systems, urban resilience is strictly linked to the proper functioning of urban services and the knowledge of the cascading effects that may occur in the case of the failure of one or more critical infrastructures of a particular strategic sector. In this context, the aim of this paper is to assess urban resilience through the analysis of the behavior of the main urban services in case of pluvial floods for current and future rainfall conditions due to climate change. A comprehensive flood risk assessment including direct, indirect, tangible and intangible impacts has been performed using cutting edge sectorial and integrated models to analyze the resilience of different urban services (urban drainage, traffic, electric and waste sectors) and their cascade effects. In addition, the paper shows how the information generated by these models can be employed to feed a more holistic analysis to provide a general overview of the city’s resilience in the case of extreme rainfall events. According to the obtained results, Barcelona could suffer a significant increase of socio-economic impacts due to climate change if adaptation measures are not adopted. In several cases, these impacts have been geographically distributed showing the specific situation of each district of the city for current and future scenarios. This information is essential for the justification and prioritization of the implementation of adaptation measures.This research was funded by Horizon2020 Programme, Grant Agreement No. 700174. This paper presents some of the results achieved in the framework of the RESCCUE project (Resilience to Cope with Climate Change in Urban Areas—a multisectoral approach focusing on water) (www.resccue.eu). RESCCUE is a research project funded by the European Commission under the H2020 program, and its main goal is to provide methodologies and tools for the evaluation, planning and management of urban resilience in the context of climate change.Peer ReviewedPostprint (published version

Optomechanical devides for mechanobiological fingerprinting

Resumen del trabajo presentado en el Frontiers of Nanomechanical Systems (FSN2021), celebraod de forma virtual del 19 al 21 de enero de 2021Twenty years have passed since the first detection of biomolecular recognition using micromechanical systems[1]. In the last two decades, micro- nanomechanical systems have been refined to achieve amazing detection limits in force and mass that have enabled different schemes for ultrasensitive measurements of biological interactions as well as new ways of biological spectrometry. More recently, these figures of merit have been improved by coupling optical cavities to mechanical systems. In this talk, I will review the use of micro- nanomechanical systems for mechanobiological fingerprinting of biological entities, particularizing in the contributions of our group [2]. An essential core of this topic is the discussion about the mechanical coupling between a biological particle and a mechanical resonator, an issue that it is has been often oversimplified. We show that the biomechanical coupling that emerges between a bioparticle and a mechanical resonator is more complex than previously expect and it can give rise to different interaction regimes, in which the resonator response is dominated by different physical parameters of the analyte [3-4]. In particular, we will show experiments done with a variety of micro- nano- optomechanical systems using different measurement schemes where the mass, the stiffness and even the vibration modes of single biological entities can be measured with high sensitivity. It is now widely appreciated the essential role of mechanics in relevant biological processes and how disease can be revealed as changes in the mechanical properties of biological matter. I am pretty sure that future developments in optomechanical devices will contribute for major understanding of diseases as well as for new avenues in diagnosis and therapy

Molecular characterization of new FBXL4 mutations in patients with mtDNA depletion syndrome

Encephalomyopathic mitochondrial DNA (mtDNA) depletion syndrome 13 (MTDPS13) is a rare genetic disorder caused by defects in F-box leucine-rich repeat protein 4 (FBXL4). Although FBXL4 is essential for the bioenergetic homeostasis of the cell, the precise role of the protein remains unknown. In this study, we report two cases of unrelated patients presenting in the neonatal period with hyperlactacidemia and generalized hypotonia. Severe mtDNA depletion was detected in muscle biopsy in both patients. Genetic analysis showed one patient as having in compound heterozygosis a splice site variant c.858+5G>C and a missense variant c.1510T>C (p.Cys504Arg) in FBXL4. The second patient harbored a frameshift novel variant c.851delC (p.Pro284LeufsTer7) in homozygosis. To validate the pathogenicity of these variants, molecular and biochemical analyses were performed using skin-derived fibroblasts. We observed that the mtDNA depletion was less severe in fibroblasts than in muscle. Interestingly, the cells harboring a nonsense variant in homozygosis showed normal mtDNA copy number. Both patient fibroblasts, however, demonstrated reduced mitochondrial transcript quantity leading to diminished steady state levels of respiratory complex subunits, decreased respiratory complex IV (CIV) activity, and finally, low mitochondrial ATP levels. Both patients also revealed citrate synthase deficiency. Genetic complementation assays established that the deficient phenotype was rescued by the canonical version of FBXL4, confirming the pathological nature of the variants. Further analysis of fibroblasts allowed to establish that increased mitochondrial mass, mitochondrial fragmentation, and augmented autophagy are associated with FBXL4 deficiency in cells, but are probably secondary to a primary metabolic defect affecting oxidative phosphorylation

Recommendations for reporting equivalent black carbon (eBC) mass concentrations based on long-term pan-European in-situ observations

A reliable determination of equivalent black carbon (eBC) mass concentrations derived from filter absorption photometers (FAPs) measurements depends on the appropriate quantification of the mass absorption cross-section (MAC) for converting the absorption coefficient (babs) to eBC. This study investigates the spatial–temporal variability of the MAC obtained from simultaneous elemental carbon (EC) and babs measurements performed at 22 sites. We compared different methodologies for retrieving eBC integrating different options for calculating MAC including: locally derived, median value calculated from 22 sites, and site-specific rolling MAC. The eBC concentrations that underwent correction using these methods were identified as LeBC (local MAC), MeBC (median MAC), and ReBC (Rolling MAC) respectively. Pronounced differences (up to more than 50 %) were observed between eBC as directly provided by FAPs (NeBC; Nominal instrumental MAC) and ReBC due to the differences observed between the experimental and nominal MAC values. The median MAC was 7.8 ± 3.4 m2 g-1 from 12 aethalometers at 880 nm, and 10.6 ± 4.7 m2 g-1 from 10 MAAPs at 637 nm. The experimental MAC showed significant site and seasonal dependencies, with heterogeneous patterns between summer and winter in different regions. In addition, long-term trend analysis revealed statistically significant (s.s.) decreasing trends in EC. Interestingly, we showed that the corresponding corrected eBC trends are not independent of the way eBC is calculated due to the variability of MAC. NeBC and EC decreasing trends were consistent at sites with no significant trend in experimental MAC. Conversely, where MAC showed s.s. trend, the NeBC and EC trends were not consistent while ReBC concentration followed the same pattern as EC. These results underscore the importance of accounting for MAC variations when deriving eBC measurements from FAPs and emphasize the necessity of incorporating EC observations to constrain the uncertainty associated with eBC.</p

GDF-15 is elevated in children with mitochondrial diseases and is induced by mitochondrial dysfunction

Background We previously described increased levels of growth and differentiation factor 15 (GDF-15) in skeletal muscle and serum of patients with mitochondrial diseases. Here we evaluated GDF-15 as a biomarker for mitochondrial diseases affecting children and compared it to fibroblast-growth factor 21 (FGF-21). To investigate the mechanism of GDF-15 induction in these pathologies we measured its expression and secretion in response to mitochondrial dysfunction. Methods We analysed 59 serum samples from 48 children with mitochondrial disease, 19 samples from children with other neuromuscular diseases and 33 samples from aged-matched healthy children. GDF-15 and FGF-21 circulating levels were determined by ELISA. Results Our results showed that in children with mitochondrial diseases GDF-15 levels were on average increased by 11-fold (mean 4046pg/ml, 1492 SEM) relative to healthy (350, 21) and myopathic (350, 32) controls. The area under the curve for the receiver-operating-characteristic curve for GDF-15 was 0.82 indicating that it has a good discriminatory power. The overall sensitivity and specificity of GDF-15 for a cut-off value of 550pg/mL was 67.8% (54.4%-79.4%) and 92.3% (81.5%-97.9%), respectively. We found that elevated levels of GDF-15 and or FGF-21 correctly identified a larger proportion of patients than elevated lev- els of GDF-15 or FGF-21 alone. GDF-15, as well as FGF-21, mRNA expression and protein secretion, were significantly induced after treatment of myotubes with oligomycin and that levels of expression of both factors significantly correlated. Conclusions Our data indicate that GDF-15 is a valuable serum quantitative biomarker for the diagnosis of mitochondrial diseases in children and that measurement of both GDF-15 and FGF-21 improves the disease detection ability of either factor separately. Finally, we demonstrate for the first time that GDF-15 is produced by skeletal muscle cells in response to mitochon- drial dysfunction and that its levels correlate in vitro with FGF-21 level

Results of the first European Source Apportionment intercomparison for Receptor and Chemical Transport Models

In this study, the performance of the source apportionment model applications were evaluated by comparing the model results provided by 44 participants adopting a methodology based on performance indicators: z-scores and RMSEu, with pre-established acceptability criteria. Involving models based on completely different and independent input data, such as receptor models (RMs) and chemical transport models (CTMs), provided a unique opportunity to cross-validate them. In addition, comparing the modelled source chemical profiles, with those measured directly at the source contributed to corroborate the chemical profile of the tested model results. The most used RM was EPA- PMF5. RMs showed very good performance for the overall dataset (91% of z-scores accepted) and more difficulties are observed with SCE time series (72% of RMSEu accepted). Industry resulted the most problematic source for RMs due to the high variability among participants. Also the results obtained with CTMs were quite comparable to their ensemble reference using all models for the overall average (>92% of successful z-scores) while the comparability of the time series is more problematic (between 58% and 77% of the candidates’ RMSEu are accepted). In the CTM models a gap was observed between the sum of source contributions and the gravimetric PM10 mass likely due to PM underestimation in the base case. Interestingly, when only the tagged species CTM results were used in the reference, the differences between the two CTM approaches (brute force and tagged species) were evident. In this case the percentage of candidates passing the z-score and RMSEu tests were only 50% and 86%, respectively. CTMs showed good comparability with RMs for the overall dataset (83% of the z-scores accepted), more differences were observed when dealing with the time series of the single source categories. In this case the share of successful RMSEu was in the range 25% - 34%.JRC.C.5-Air and Climat