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1.
Sci Total Environ ; 867: 161449, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36623647

RESUMEN

Ozone (O3) pollution is a persistent problem in many regions of Spain, so understanding O3 precursor emissions and trends is essential to design effective control strategies. We estimated the impact of Non-Methane Volatile Organic Compounds (NMVOC) species upon O3 formation potential (OFP) using the maximum incremental reactivity approach. For this, we developed a speciated NMVOC emission inventory for Spain from 2010 to 2019 combining national reported emissions with state-of-the-art speciation profiles, which resulted in a database of emissions for over 900 individual NMVOC species and 153 individual sectors. Additionally, we analysed 2030 emission projections to quantify the expected impact of planned measures on future OFP levels. Overall, the main activities contributing to OFP in Spain are paint manufacturing and applications (20 %), manure management (16 %), and domestic solvent use (6 %). These activities contribute unevenly across regions. The more urbanised areas report a larger contribution from the solvent sector (64 % in Madrid), while in rural areas, manure management and agricultural waste burning gain importance (24 % in Extremadura), indicating that local control measures should be implemented. The top 10 NMVOC species contributing to OFP are ethanol, ethene, xylenes, propene, toluene, formaldehyde, 1,3-butadiene, styrene, n-butane, and cyclopentane, which together are responsible for 54 % of the total OFP. Our trend analysis indicates a reduction of NMVOC emissions and OFP of -5 % and -10 % between 2010 and 2019, respectively. The larger decrease in OFP is driven by a bigger reduction in xylenes (-29 %) and toluene (-28 %) from paint application industries and the road transport sector. By 2030 a significant increase (+37 %) in the OFP from the public electricity sector is expected due to the planned increase in biomass use for power generation. Our results indicate that policies should focus on paint reformulation, limiting aerosol products, and implementing NMVOC control devices in future biomass power plants.

2.
Sci Total Environ ; 777: 144579, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33677295

RESUMEN

The Guadalquivir Valley is one of three major O3 hotspots in Spain. An airborne and surface measurement campaign was carried out from July 9th to 11th, 2019 to quantify the local/regional O3 contributions using experimental approaches. Air quality and meteorology data from surface measurements, a microlight aircraft, a helium balloon, and remote sensing data (TROPOMI-NO2-ESA) were used to obtain the 3D distribution of O3 and various tracer pollutants. O3 accumulation over 2.5 days started with inputs from oceanic air masses transported inland by sea breezes, which drew O3 and its precursors from a local/regional origin to the northeastern end of the basin. The orographic-meteorological setting of the valley caused vertical recirculation of the air masses inside the valley that caused the accumulation by increasing regional background O3 concentration by 25-30 ppb. Furthermore, possible Mediterranean O3 contributions and additional vertical recirculation through the entrainment zone of the convective boundary layer also contributed. Using particulate matter finer than 2.5 µm (PM2.5), ultrafine particles (UFP), and black carbon (BC) as tracers of local sources, we calculated that local contributions increased regional O3 levels by 20 ppb inside specific pollution plumes transported by the breeze into the valley, and by 10 ppb during midday when flying over an area with abundant agricultural burning during the morning. Air masses that crossed the southern boundaries of the Betic system at mid-altitude (400-1850 m a.s.l.) on July 10th and 11th may have provided additional O3. Meanwhile, a decreasing trend at high altitudes (3000-5000 m a.s.l.) was observed, signifying that the impact of stratospheric O3 intrusion decreased during the campaign.

3.
Environ Int ; 130: 104867, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31207476

RESUMEN

We review the major features of desert dust outbreaks that are relevant to the assessment of dust impacts upon human health. Our ultimate goal is to provide scientific guidance for the acquisition of relevant population exposure information for epidemiological studies tackling the short and long term health effects of desert dust. We first describe the source regions and the typical levels of dust particles in regions close and far away from the source areas, along with their size, composition, and bio-aerosol load. We then describe the processes by which dust may become mixed with anthropogenic particulate matter (PM) and/or alter its load in receptor areas. Short term health effects are found during desert dust episodes in different regions of the world, but in a number of cases the results differ when it comes to associate the effects to the bulk PM, the desert dust-PM, or non-desert dust-PM. These differences are likely due to the different monitoring strategies applied in the epidemiological studies, and to the differences on atmospheric and emission (natural and anthropogenic) patterns of desert dust around the world. We finally propose methods to allow the discrimination of health effects by PM fraction during dust outbreaks, and a strategy to implement desert dust alert and monitoring systems for health studies and air quality management.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Polvo/análisis , Aerosoles , Movimientos del Aire , Monitoreo del Ambiente
4.
Euro Surveill ; 14(5)2009 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-19215714

RESUMEN

The countries around the Mediterranean Sea share epidemiological characteristics and public health problems. In 2006 the EpiSouth Project was started as a framework for collaboration for communicable diseases surveillance and training in the Mediterranean Basin. As of December 2008, 26 countries from southern Europe, the Balkans, North Africa and the Middle-East are members of EpiSouth and several international organisations and institutions collaborate: the European Commission (EC), the European Centre for Disease Prevention and Control (ECDC), the Italian Ministry of Work, Health and Social Policies and the World Health Organization (WHO). The project is coordinated by the Italian national public health institute and three work packages (WPs) Cross-border epidemic intelligence, vaccine preventable diseases and migrants and Cross-border emerging zoonoses are operated by the national institutes of France, Bulgaria and Greece. These WPs constitute technical pillars on which the project develops. Networking and Training are WPs dedicated to capacity building and are run by the Padua Teaching Hospital (Italy) and the Spanish national public health institute. A steering committee guides EpiSouth's activities while all countries collaborate through WP steering teams and focal points. A number of outcomes have been accomplished and documents with results are available from the EpiSouth website which hosts a public website and a restricted area for direct sharing of information among the participants. Five electronic bulletins were published, two trainings for 63 participants performed, national epidemic intelligence systems were evaluated, a preliminary survey on vaccine-preventable diseases and migrants performed, and a list of priorities for emerging zoonoses in the Mediterranean area was selected. Overall the network succeeded in creating cohesion, mutual trust and concrete collaboration on cross-border public health issues in a geographical area that is not addressed as a whole by any other initiative or organisation.


Asunto(s)
Control de Enfermedades Transmisibles/organización & administración , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Redes Comunitarias/organización & administración , Brotes de Enfermedades/prevención & control , Brotes de Enfermedades/estadística & datos numéricos , Vigilancia de la Población/métodos , Control de Enfermedades Transmisibles/métodos , Enfermedades Transmisibles Emergentes/diagnóstico , Humanos , Región Mediterránea/epidemiología
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(5 Pt 2): 056201, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-16089628

RESUMEN

We investigate the onset of chaotic dynamics of the one-dimensional discrete nonlinear Schrödinger equation with periodic boundary conditions in the presence of a single on-site defect. This model describes a ring of weakly coupled Bose-Einstein condensates with attractive interactions. We focus on the transition to global stochasticity in three different scenarios as the defect is changed. We make use of a suitable Poincaré section and study different families of stationary solutions, where certain bifurcations lead to global stochasticity. The global stochasticity is characterized by chaotic symbolic synchronization between the population inversions of certain pairs of condensates. We have seen that the Poincaré cycles are useful to gain insight in the dynamics of this Hamiltonian system. Indeed, the return maps of the Poincaré cycles have been used successfully to follow the orbit along the stochastic layers of different resonances in the chaotic self-trapping regime. Moreover, the time series of the Poincaré cycles suggests that in the global stochasticity regime the dynamics is, to some extent, Markovian, in spite of the fact that the condensates are phase locked with almost the same phase. This phase locking induces a peculiar local interference of the matter waves of the condensates.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(3 Pt 2): 036603, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15089426

RESUMEN

We have considered the discrete nonlinear Schrödinger equation (DNLSE) with periodic boundary conditions in the context of coupled Kerr waveguides. The presence of a defect in the central oscillator equation can induce quasiperiodic or large chaotic amplitude oscillations. As for the quasiperiodic dynamics, an enhancement of the amplitude correlations in certain oscillator pairs can take place. However, when the array dynamics becomes chaotic, these correlations are destroyed, and, for suitable defects, synchronization, in the information sense, of certain signals arises in this Hamiltonian system. A numerical continuation analysis clarifies the onset of this dynamical regime. In this case, phase synchronization follows with a peculiar distribution of the Liapunov exponents. These effects occur for initial conditions in a small neighborhood of a family of stationary solutions. We have also found a regime characterized by persistent localized chaotic amplitudes. We have generalized these results to take into account birefringent effects in waveguides.


Asunto(s)
Oscilometría , Modelos Estadísticos , Modelos Teóricos , Movimiento , Dinámicas no Lineales , Fenómenos Físicos , Física
7.
Aten Primaria ; 22(10): 655-60, 1998 Dec.
Artículo en Español | MEDLINE | ID: mdl-9931562

RESUMEN

OBJECTIVE: To identify the risk factors responsible for the high demand for care from patients coming via casualty to the general medicine and paediatrics clinics at our health centre. DESIGN: Observational study. SETTING: Primary care. Panaderas II Health Centre, Madrid. PATIENTS: All the patients attending the paediatrics and/or general medicine clinic via casualty in October 1996 were included (636). At random, 209 patients were selected from those who attended on demand. MEASUREMENTS AND MAIN RESULTS: For each patient the following variables were gathered: emergency/appointment, age, sex, room assigned, whether they asked for appointment, hour of call, type of emergency, clinic where seen, delay in appointment, assigned to which doctor's list, paediatrician/general practitioner. Being a girl was a significant risk factor in paediatrics casualty. In general practice, belonging to clinics with longer waits for an appointment and more patients per doctor (OR > 2) brought a higher risk, though not significantly, of attendance for consultation via casualty. Young people attended more frequently via casualty (chi 2 = 6.55, p = 0.01). CONCLUSIONS: The increase in each doctor's patient list generates attendance overload and anomalous paths for consultation. Limiting accessibility of the population does not control demand and increases the route via casualty. The doctor should assess personally those urgent requests not controlled by the clerical staff. Special attention to the young is probably needed to find the causes of the increase in emergency consultations among this population group.


Asunto(s)
Servicios Médicos de Urgencia , Atención Primaria de Salud , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Factores Sexuales , España
8.
Biophys J ; 61(5): 1394-401, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-19431832

RESUMEN

Flow calorimetry has been used to study the interaction of glycine with protons in water at temperatures of 298.15, 323.15, and 348.15 K and pressures up to 12.50 MPa. By combining the measured heat for glycine solutions titrated with NaOH with the heat of ionization for water, the enthalpy of protonation of glycine is obtained. The reaction is exothermic at all temperatures and pressures studied. The effect of pressure on the enthalpy of reaction is very small. The experimental heat data are analyzed to yield equilibrium constant (K), enthalpy change (DeltaH), and entropy change (DeltaS) values for the protonation reaction as a function of temperature. These values are compared with those reported previously at 298.15 K. The DeltaH and DeltaS values increase (become more positive), whereas log K values decrease, as temperature increases. The trends for DeltaH and DeltaS with temperature are opposite to those reported previously for the protonation of several alkanolamines. However, log K values for proton interaction with both glycine and the alkanolamines decrease with increasing temperature. The effect of the nitrogen atom substituent on log K for protonation of glycine and alkanolamines is discussed in terms of changes in long-range and short-range solvent effects. These effects are used to explain the difference in DeltaH and DeltaS trends between glycine protonation and those found earlier for alkanolamine protonation.

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