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1.
Environ Sci Technol ; 58(32): 14338-14347, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39078311

RESUMEN

Microplastics (MP) have been recognized as an emerging atmospheric pollutant, yet uncertainties persist in their emissions and concentrations. With a bottom-up approach, we estimate 6-hourly MP fluxes at the ocean-atmosphere interface, using as an input the monthly ocean surface MP concentrations simulated by the global oceanic model (NEMO/PISCES-PLASTIC, Nucleus for European Modeling of the Ocean, Pelagic Interaction Scheme for Carbon and Ecosystem Studies), a size distribution estimate for the MP in the micrometer range, and a sea salt emission scheme. The atmospheric dispersion is then simulated with the Lagrangian model FLEXPART. We identify hotspot sources in the tropical regions and highlight the seasonal variability of emissions, atmospheric concentrations, and deposition fluxes both on land and ocean surfaces. Due to the variability of MP concentration during the year, the MP flux from the sea surface appears to follow a seasonality opposite to that of sea salt aerosol emissions. The comparison with existing observations of MP in the marine atmosphere suggests an underestimation of one to 2 orders of magnitude in our current knowledge of the MP in the oceans' surface. In addition, we show that the MP in the micrometer range is transported efficiently around the globe and can penetrate and linger in the stratosphere over time scales of months. The interaction of these particles with the chemistry and physics of the atmosphere is still mostly unknown and deserves to be further investigated.


Asunto(s)
Atmósfera , Microplásticos , Océanos y Mares , Atmósfera/química , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Estaciones del Año , Agua de Mar/química
2.
Environ Sci Technol ; 58(22): 9741-9749, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38767840

RESUMEN

Microplastics (MPs) are emerging as an atmospheric pollutant. Here, we present a method of estimating MP resuspension with mineral dust in bare soil based on reported MP mass in soils, their enrichment in suspended dust relative to soil, and a mineral dust resuspension scheme. Using the estimated resuspensions, we simulate the global atmospheric MP transport and deposition using the dispersion model FLEXPART for two particle shape scenarios, spheres, and fibers. We estimate the uncertainties using a Monte Carlo technique that varies input data parameters within their reported ranges. The total MP resuspensions are estimated at about 104 (48-110) tonnes yr-1. We find that bare soils in West Asia and North Africa are the main source regions. FLEXPART results show that fibers have higher concentrations in the atmosphere and are dispersed more widely than spheres. Annually, 75 (43-83) tonnes of microfibers are deposited on land and 29 (18-33) tonnes in the oceans. Resuspended MPs can even reach remote regions, such as the Arctic. The results suggest that areas with bare soils can be an important MP source; however, further research on the factors that affect resuspension is needed.


Asunto(s)
Atmósfera , Microplásticos , Suelo , Microplásticos/análisis , Atmósfera/química , Suelo/química , Contaminantes del Suelo/análisis , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis , Polvo/análisis , Método de Montecarlo
3.
Environ Sci Technol ; 58(1): 671-682, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38150408

RESUMEN

The deposition of airborne microplastic particles, including those exceeding 1000 µm in the longest dimension, has been observed in the most remote places on earth. However, their deposition patterns are difficult to reproduce using current atmospheric transport models. These models usually treat particles as perfect spheres, whereas the real shapes of microplastic particles are often far from spherical. Such particles experience lower settling velocities compared to volume equivalent spheres, leading to longer atmospheric transport. Here, we present novel laboratory experiments on the gravitational settling of microplastic fibers in air and find that their settling velocities are reduced by up to 76% compared to those of the spheres of the same volume. An atmospheric transport model constrained with the experimental data shows that shape-corrected settling velocities significantly increase the horizontal and vertical transport of particles. Our model results show that microplastic fibers of about 1 mm length emitted in populated areas are more likely to reach extremely remote regions of the globe, including the high Arctic, which is not the case for spheres of equivalent volume. We also calculate that fibers with lengths of up to 100 µm settle slowly enough to be lifted high into the stratosphere, where degradation by ultraviolet radiation may release chlorine and bromine, thus potentially damaging the stratospheric ozone layer. These findings suggest that the growing environmental burden and still increasing emissions of plastic pose multiple threats to life on earth.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis , Atmósfera , Monitoreo del Ambiente
4.
Environ Sci Technol ; 57(44): 16834-16842, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37856673

RESUMEN

Tar balls are brown carbonaceous particles that are highly viscous, spherical, amorphous, and light absorbing. They are believed to form in biomass burning smoke plumes during transport in the troposphere. Tar balls are also believed to have a significant impact on the Earth's radiative balance, but due to poorly characterized optical properties, this impact is highly uncertain. Here, we used two nighttime samples to investigate the chemical composition and optical properties of individual tar balls transported in the free troposphere to the Climate Observatory "Ottavio Vittori" on Mt. Cimone, Italy, using multimodal microspectroscopy. In our two samples, tar balls contributed 50% of carbonaceous particles by number. Of those tar balls, 16% were inhomogeneously mixed with other constituents. Using electron energy loss spectroscopy, we retrieved the complex refractive index (RI) for a wavelength range from 200 to 1200 nm for both inhomogeneously and homogeneously mixed tar balls. We found no significant difference in the average RI of inhomogeneously and homogeneously mixed tar balls (1.40-0.03i and 1.36-0.03i at 550 nm, respectively). Furthermore, we estimated the top of the atmosphere radiative forcing using the Santa Barbara DISORT Atmospheric Radiative Transfer model and found that a layer of only tar balls with an optical depth of 0.1 above vegetation would exert a positive radiative forcing ranging from 2.8 W m-2 (on a clear sky day) to 9.5 W m-2 (when clouds are below the aerosol layer). Understanding the optical properties of tar balls can help reduce uncertainties associated with the contribution of biomass-burning aerosol in current climate models.


Asunto(s)
Contaminantes Atmosféricos , Clima , Atmósfera/química , Aerosoles/análisis , Italia , Contaminantes Atmosféricos/análisis
5.
Pathogens ; 11(11)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36365029

RESUMEN

(1) Background: Infections in pregnancy can lead to miscarriage, premature birth, infections in newborns, and developmental disabilities in babies. Infected infants, symptomatic at birth, can have long-term sequelae, and asymptomatic babies are also at increased risk of developing long-term sensorineural outcomes. Targeted therapy of the pregnant mother can reduce fetal and neonatal harm. (2) Aim of the study: To explore the association between symptoms and time of onset of long-term sequelae in infected children born from mothers who contracted an infection during pregnancy, by a long-term multidisciplinary follow-up. (3) Methods: For up to 2−4 years, we evaluated cognitive, motor, audiological, visual, and language outcomes in infants with symptomatic and asymptomatic congenital infections and in uninfected infants. (4) Results: 186 infants born from women who acquired Cytomegalovirus infection (n = 103), Toxoplasma infection (n = 50), and Syphilis (n = 33) during pregnancy were observed. Among them, 119 infants acquired the infection in utero. Infected infants, symptomatic at birth, obtained lower scores on the Cognitive and Motor Scale on Bayley-III compared to asymptomatic and uninfected infants (p = 0.026; p = 0.049). Many severe or moderate sequelae rose up within the first year of life. At 24 months, we observed sequelae in 24.6% (14/57) of infected children classified as asymptomatic at birth, compared to 68.6% (24/35) of symptomatic ones (χ2 = 15.56; p < 0.001); (5) Conclusions: Infected babies symptomatic at birth have a worse prognosis than asymptomatic ones. Long-term sequelae may occur in infected children asymptomatic at birth after the first year of life. Multidisciplinary follow-up until 4−6 years of age should be performed in all infected children, regardless of the presence of symptoms at birth.

6.
Nat Commun ; 13(1): 5290, 2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36075920

RESUMEN

Frequency and intensity of warm and moist air-mass intrusions into the Arctic have increased over the past decades and have been related to sea ice melt. During our year-long expedition in the remote central Arctic Ocean, a record-breaking increase in temperature, moisture and downwelling-longwave radiation was observed in mid-April 2020, during an air-mass intrusion carrying air pollutants from northern Eurasia. The two-day intrusion, caused drastic changes in the aerosol size distribution, chemical composition and particle hygroscopicity. Here we show how the intrusion transformed the Arctic from a remote low-particle environment to an area comparable to a central-European urban setting. Additionally, the intrusion resulted in an explosive increase in cloud condensation nuclei, which can have direct effects on Arctic clouds' radiation, their precipitation patterns, and their lifetime. Thus, unless prompt actions to significantly reduce emissions in the source regions are taken, such intrusion events are expected to continue to affect the Arctic climate.

7.
Front Pediatr ; 10: 881516, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669403

RESUMEN

Background: Non-polio-enteroviruses (EV) and human parechoviruses (HPeV) are small RNA viruses, which in newborns cause infections with a wide range of severity. Today molecular biology tools allow us to diagnose viral meningitis in neonates, sparing patients from useless antibiotics. Data on neurodevelopmental outcome of children who contract enterovirus meningitis in early childhood are still limited in the literature. Aims: To evaluate the neurodevelopmental outcome of newborns with documented enterovirus and parechovirus meningitis contracted within the first months of life. Methods: Enterovirus and parechovirus were detected on cerebrospinal fluid (CSF) and plasma by RT-PCR. The virological typing was done according to WHO recommendations. During the hospitalization each neonate underwent many diagnostic and instrumental examinations, to evaluate any neurological lesions attributable to the infection. After the discharge children entered in an outpatient interdisciplinary assessment process, comprehensive of the administration of Bayley III scales up to 12 months old. Results: We observed longitudinally 30 children, born at term (mean GA 39.7 ± 0.8 weeks, mean birthweight was 3,457 ± 405 grams), who contracted enterovirus and parechovirus meningitis within the first month of life (mean age at diagnosis was 15.8 ± 7.33 days). We were able to perform the genetic typing only on 15/30 (50.0%) cerebrospinal fluid (CSF) samples from 15 neonates. We found MRI anomalies in 9/26 observed neonates (34.6%): one of them presented brainstem abnormality that are specific of enteroviral central nervous system (CNS) involvement. During the follow up children displayed an overall normal neurodevelopment and no deficit in visual and hearing areas. The mean cognitive (105.19 ± 8.71), speech (100.23 ± 8.22) and motor (97.00 ± 8.98) composite scores, assessed by Bayley III, were normal in 29/30 (96.7%). Despite this, children with pathological brain magnetic resonance imaging (MRI) scored significantly lower (p = 0.01) than children with normal brain MRI on cognitive subscale at 12 months of life. Conclusions: Early enterovirus infections can be associated to brain MRI abnormalities, more frequently the earlier the infection. Although within a normal range, our children with pathological brain MRI scored significantly lower than those with normal brain MRI on cognitive subscale at 12 months of life.

8.
Am J Perinatol ; 39(13): 1478-1483, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34883523

RESUMEN

OBJECTIVE: The objective of this paper was to assess how hospital and outpatient clinic policies changes due to the coronavirus disease 2019 (COVID-19) pandemic impact pediatric medical traumatic stress (PMTS) symptoms in mothers of newborns admitted in a neonatal intensive care unit (NICU). STUDY DESIGN: Observational case-control study included the comparison between mothers of infants admitted in the NICU at birth during the COVID-19 pandemic and mothers of infants admitted in the NICU before the COVID-19 pandemic. The control group was selected matching 1:1 with the study group for the following infants' clinical variables: gender, type of pathology, gestational age, weight at birth, day of recovery, ventilator time days, and associated malformations. The Italian version of the Impact of Event Scale-Revised (IES-R) was used as a measure of PMTS. RESULT: Mothers of the study group (50) scored significantly higher than mothers of the control group on three of four scales of IES-R ("IES-R total": F = 6.70; p = 0.011; IES-R subscale "intrusion": F = 7.45; p = 0.008; IES-R subscale "avoidance": F = 8.15; p = 0.005). A significantly higher number of mothers in the study group scored above the IES-R total clinical cut-off compared with mothers of control group (72 vs. 48%; Chi2 = 6.00; p = 0.012). CONCLUSION: The COVID-19 pandemic acted as superimposed stress in mothers of newborns admitted in the NICU at birth determining high levels of PMTS. Clinicians and researchers should identify and implement novel strategies to provide family-centered care during the COVID-19 pandemic and beyond. KEY POINTS: · COVID-19 acted as superimposed stress on NICU population.. · PMTS in mothers got significantly worse during the COVID-19 pandemic.. · Alert on long-term consequences on child development..


Asunto(s)
COVID-19 , Unidades de Cuidado Intensivo Neonatal , COVID-19/epidemiología , Estudios de Casos y Controles , Niño , Estrenos , Femenino , Humanos , Lactante , Recién Nacido , Madres , Pandemias , Compuestos de Piridinio
9.
IEEE Trans Pattern Anal Mach Intell ; 44(9): 5516-5528, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-33798074

RESUMEN

Human adaptability relies crucially on learning and merging knowledge from both supervised and unsupervised tasks: the parents point out few important concepts, but then the children fill in the gaps on their own. This is particularly effective, because supervised learning can never be exhaustive and thus learning autonomously allows to discover invariances and regularities that help to generalize. In this paper we propose to apply a similar approach to the problem of object recognition across domains: our model learns the semantic labels in a supervised fashion, and broadens its understanding of the data by learning from self-supervised signals on the same images. This secondary task helps the network to focus on object shapes, learning concepts like spatial orientation and part correlation, while acting as a regularizer for the classification task over multiple visual domains. Extensive experiments confirm our intuition and show that our multi-task method, combining supervised and self-supervised knowledge, provides competitive results with respect to more complex domain generalization and adaptation solutions. It also proves its potential in the novel and challenging predictive and partial domain adaptation scenarios.


Asunto(s)
Algoritmos , Semántica , Niño , Humanos , Aprendizaje Automático Supervisado
10.
Artículo en Inglés | MEDLINE | ID: mdl-33086703

RESUMEN

Background: Delays in learning skills have been extensively reported for very preterm children. However, few studies have examined academic achievement profiles in Italian preterm children as a function of their neonatal immaturity. Methods: A cross-sectional study was performed that included 82 healthy Italian children born very and extremely preterm (without major neurosensory outcomes; IQ ≥85). Children were evaluated for academic and neurocognitive performances at the second cycle of primary school. Results: Healthy preterm children showed on average academic and neurocognitive profiles that did not differ according to gestational age. Impairment was seen to one or more learning domains in 14.6% of the healthy preterm children. Conclusions: Italian children born very and extremely preterm without major neurosensory damage and/or cognitive delay showed on average learning and neurocognitive profiles within the normal range, regardless of gestational age. Nevertheless, they showed higher proportions of learning impairment than a normative Italian population during their final years of primary school. Healthcare providers should be aware of this result, and long-term surveillance should be organized to promptly identify those children who are in need of therapeutic intervention.


Asunto(s)
Trastornos del Conocimiento , Inteligencia , Discapacidades para el Aprendizaje , Nacimiento Prematuro , Niño , Estudios Transversales , Humanos , Recién Nacido , Italia/epidemiología , Masculino , Instituciones Académicas
11.
Front Pediatr ; 8: 527, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33042903

RESUMEN

Perinatal asphyxia triggers an acute inflammatory response in the injured brain. Complement activation and neuroinflammation worsen brain damage after a systemic ischemia/reperfusion insult. The increase of mannose binding lectin (MBL) during asphyxia may contribute to the brain damage, via activation of the complement lectin pathway. The possible role of MBL2 gene variants in influencing the severity of post-asphyxia brain injuries is still unexplored. This retrospective study included 53 asphyxiated neonates: 42 underwent therapeutic hypothermia (TH) and 11 did not because they were admitted to the NICU later than 6 h after the hypoxic insult. Blood samples from TH-treated and untreated patients were genotyped for MBL2 gene variants, and biomarker plasma levels (MBL and S100 B protein) were measured at different time points: during hypothermia, during rewarming, and at 7-10 days of life. The timing of blood sampling, except for the T1 sample, was the same in untreated infants. Highest (peak) levels of MBL and MBL2 genotypes were correlated to neuroimaging brain damage or death and long-term neurodevelopmental delay. MBL2 wild-type genotype was associated with the highest MBL levels and worst brain damage on MRI (p = 0.046) at 7-10 days after hypoxia. MBL increased in both groups and S100B decreased, slightly more in treated than in untreated neonates. The progressive increase of MBL (p = 0.08) and to be untreated with TH (p = 0.08) increased the risk of brain damage or death at 7-10 days of life, without affecting neurodevelopmental outcomes at 1 year. The effect of TH on MBL plasma profiles is uncertain.

12.
Early Hum Dev ; 113: 1-6, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28697405

RESUMEN

BACKGROUND: Premature birth is often associated with neurodevelopmental difficulties throughout childhood. In the first three years of life, the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III) constitute one of the most used tools for assessing child development. Since Bayley-III original norms are based on United States (US) population, it remains uncertain whether their use in other countries (e.g., European) is appropriate. AIMS: This research aimed to examine neurodevelopment of preterm infants and full-term infants, using Bayley-III US norms in comparison to Italian (IT) norms. Patterns of developmental outcomes for both infant groups were also explored. METHODS: 104 preterm and 58 full-term infants were included in the study. Bayley-III was used for neurodevelopmental assessment at 1year of corrected age, considering both IT and US norms for scores computation. RESULTS: Comparing scores obtained with IT vs US norms, differences in means were all significant across five subscales (p<0.05 at least) for preterm infants, whereas for full-term peers significant differences were found only for Receptive Language and Fine Motor subscales (p<0.001). Effect size (η2) ranged from 0.22 to 0.94. Within each group, significant discrepancies across subscales were found. Moreover, Italian preterm infants had significantly lower performances than full-term peers, excepting for Expressive Language and Gross Motor subscales. CONCLUSIONS: As regards to Italian 1-year children, our study seems to provide evidence for the tendency of Bayley-III US norms to overestimate development compared to IT norms. These findings emphasize the need to early detect children at risk for developmental delay and to plan early intervention.


Asunto(s)
Desarrollo Infantil , Discapacidades del Desarrollo/epidemiología , Recien Nacido Prematuro/crecimiento & desarrollo , Estudios de Casos y Controles , Femenino , Humanos , Lactante , Recién Nacido , Masculino
13.
Radiat Prot Dosimetry ; 145(2-3): 202-5, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21586542

RESUMEN

Extensive radon surveys have been carried out in many countries only in dwellings, whereas surveys in workplaces are rather sparse and generally restricted to specific workplaces/activities, e.g. schools, spas and caves. Moreover, radon-prone areas are generally defined on the basis of radon surveys in dwellings, while radon regulations use this concept to introduce specific requirements in workplaces in such areas. This approach does not take into account that work activities and workplace characteristics can significantly affect radon concentration. Therefore, an extensive survey on radon in different workplaces have been carried out in a large region of Italy (Tuscany), in order to evaluate radon distribution in workplaces over the whole territory and to identify activities and workplace characteristics affecting radon concentration. The results of this extensive survey are compared with the results of the survey carried out in dwellings in the same period. The workplaces monitored were randomly selected among the main work activities in the region, including both public and industrial buildings. The survey monitored over 3500 rooms in more than 1200 buildings for two consecutive periods of ∼6 months. Radon concentration was measured by means of passive nuclear track detectors.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Vivienda , Exposición Profesional/análisis , Monitoreo de Radiación , Radón/análisis , Humanos , Lugar de Trabajo
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