131 research outputs found

    Modelling street level PM10 concentrations across Europe: source apportionment and possible futures

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    Despite increasing emission controls, particulate matter (PM) has remained a critical issue for European air quality in recent years. The various sources of PM, both from primary particulate emissions as well as secondary formation from precursor gases, make this a complex problem to tackle. In order to allow for credible predictions of future concentrations under policy assumptions, a modelling approach is needed that considers all chemical processes and spatial dimensions involved, from long-range transport of pollution to local emissions in street canyons. Here we describe a modelling scheme which has been implemented in the GAINS integrated assessment model to assess compliance with PM10 (PM with aerodynamic diameter <10 um) limit values at individual air quality monitoring stations reporting to the AirBase database. The modelling approach relies on a combination of bottom up modelling of emissions, simplified atmospheric chemistry and dispersion calculations, and a traffic increment calculation wherever applicable. At each monitoring station fulfilling a few data coverage criteria, measured concentrations in the base year 2009 are explained to the extent possible and then modelled for the past and future. More than 1850 monitoring stations are covered, including more than 300 traffic stations and 80% of the stations which exceeded the EU air quality limit values in 2009. As a validation, we compare modelled trends in the period 2000-2008 to observations, which are well reproduced. The modelling scheme is applied here to quantify explicitly source contributions to ambient concentrations at several critical monitoring stations, displaying the differences in spatial origin and chemical composition of urban roadside PM10 across Europe. Furthermore, we analyse the predicted evolution of PM10 concentrations in the European Union until 2030 under different policy scenarios. Significant improvements in ambient PM10 concentrations are expected assuming successful implementation of already agreed legislation; however, these will not be large enough to ensure attainment of PM10 limit values in hot spot locations such as Southern Poland and major European cities. Remaining issues are largely eliminated in a scenario applying the best available emission control technologies to the maximal technically feasible extent

    Synaptic and cellular changes induced by the schizophrenia susceptibility gene G72 are rescued by N-acetylcysteine treatment

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    Genetic studies have linked the primate-specific gene locus G72 to the development of schizophrenia and bipolar disorder. Transgenic mice carrying the entire gene locus express G72 mRNA in dentate gyrus (DG) and entorhinal cortex, causing altered electrophysiological properties of their connections. These transgenic mice exhibit behavioral alterations related to psychiatric diseases, including cognitive deficits that can be reversed by treatment with N-acetylcysteine, which was also found to be effective in human patients. Here, we show that G72 transgenic mice have larger excitatory synapses with an increased amount of N-methyl-d-aspartate (NMDA) receptors in the molecular layer of DG, compared with wild-type littermates. Furthermore, transgenic animals have lower number of dentate granule cells with a parallel, but an even stronger decrease in the number of excitatory synapses in the molecular layer. Importantly, we also show that treatment with N-acetylcysteine can effectively normalize all these changes in transgenic animals, resulting in a state similar to wild-type mice. Our results show that G72 transcripts induce robust alterations in the glutamatergic system at the synaptic level that can be rescued with N-acetylcysteine treatment

    Atípusos aortacoarctatiók sebészi kezelésének hosszú távú eredményei

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    Absztrakt Bevezetés: Az aortacoarctatio a leggyakoribb congenitalis cardiovascularis elváltozások egyike, azok 5–8%-ában fordul elő. Típusos előfordulási helye az isthmicus szakasz. Atípusos helyen kialakuló coarctatio az esetek mintegy 1%-ában fordul elő és többnyire súlyos hypertoniával szövődik. Célkitűzés: A szerzők célul tűzték ki a kórkép sebészi kezelési lehetőségeinek és azok hosszú távú eredményeinek ismertetését 27 beteg műtéti kezelésével szerzett tapasztalataik alapján. Módszer: A 35 évet felölelő utánkövetés során a diagnosztika és a kezelési módszerek változtak. Napjainkban a morfológiai diagnózis legáltalánosabb módszerei a komputertomográfiás angiográfia és a mágneses rezonanciás angiográfia. Az aortarekonstrukció lehetőségei az endovascularis technikák bevezetésével gazdagodtak, de atípusos aortacoartatio esetében a szerzők ma is túlnyomóan változatos sebészi megoldásokat alkalmaznak. Eredmények: A műtétek után nem veszítettek el beteget. A hypertonia minden esetben jelentősen csökkent. Gyermekkorban operált esetekben a növekedés okozta testméretváltozások 3 esetben újabb rekonstrukciós műtétet indokoltak. Következtetések: Az atípusos aortacoarctatio individuális sebészi módszerekkel eredményesen kezelhető. Gyermekkorban operált esetekben a testméret-növekedés a rekonstruált aortaszakasz revízióját teheti szükségessé. Orv. Hetil., 2016, 157(26), 1043–1051

    Why Do States Develop Multi-tier Emigrant Policies? Evidence from Egypt

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    Why do states vary their policies towards their citizens abroad, and why are some emigrant groups treated preferentially to others? The literature on the politics of international migration has yet to explore this as a separate field of inquiry, assuming that states adopt a single policy that encourages, sustains or prevents emigration abroad. Yet, in the case of Egypt, the state developed a multi-tiered policy that distinctly favoured specific communities abroad over others. I hypothesise that policy differentiation is based upon the perceived utility of the emigrant group remaining abroad versus the utility of its return. This utility is determined by two factors: the sending state’s domestic political economy priorities and its foreign policy objectives

    Photo-antagonism of the GABAA receptor

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    Neurotransmitter receptor trafficking is fundamentally important for synaptic transmission and neural network activity. GABAA receptors and inhibitory synapses are vital components of brain function, yet much of our knowledge regarding receptor mobility and function at inhibitory synapses is derived indirectly from using recombinant receptors, antibody-tagged native receptors and pharmacological treatments. Here we describe the use of a set of research tools that can irreversibly bind to and affect the function of recombinant and neuronal GABAA receptors following ultraviolet photoactivation. These compounds are based on the competitive antagonist gabazine and incorporate a variety of photoactive groups. By using site-directed mutagenesis and ligand-docking studies, they reveal new areas of the GABA binding site at the interface between receptor β and α subunits. These compounds enable the selected inactivation of native GABAA receptor populations providing new insight into the function of inhibitory synapses and extrasynaptic receptors in controlling neuronal excitation

    Final Report The potential for cost-effective air emission reductions from international shipping through designation of further Emission Control Areas in EU waters with focus on the Mediterranean Sea

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    This study explores the impacts of alternative emission control interventions for international shipping on the European Seas on relevant air pollutant emissions, examines their consequence on ambient air quality in Europe and the neighbouring regions, and explores the resulting improvements of human health. It estimates the costs of the various policy interventions, and compares them with monetized benefits on human health and other impacts. It is found that further controls of SO₂ emissions, e.g., through SO₂ emission control areas, could deliver rather fast benefits, and avoid by 2030 up to 4000 cases of premature deaths annually, and 8000 in 2050. In the longer run, by 2050, application of Tier III NOx standards could double the health benefits. Even when using the lower (most conservative) health valuation, all reduction measures examined in this report emerged as cost-effective, with monetized benefits exceeding emission control costs typically by a factor of 6 in 2030 and by a factor of 12 in 2050. Designation of the Mediterranean Sea as an Emission Control Area could by 2030 cut emissions of SO2 and NOx from international shipping by 80 and 20 percent, respectively, compared to current legislation. These additional emission reductions could avoid 4,100 cases of premature deaths in 2030 and more than 10,000 annual premature deaths in 2050. Even with the most conservative assumptions for health valuation, monetized benefits are on average 4.4 times higher than the costs in 2030 and 7.5 times higher in 2050

    Nitric Oxide Signaling Modulates Synaptic Transmission during Early Postnatal Development

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    Early γ-aminobutyric acid mediated (GABAergic) synaptic transmission and correlated neuronal activity are fundamental to network formation; however, their regulation during early postnatal development is poorly understood. Nitric oxide (NO) is an important retrograde messenger at glutamatergic synapses, and it was recently shown to play an important role also at GABAergic synapses in the adult brain. The subcellular localization and network effect of this signaling pathway during early development are so far unexplored, but its disruption at this early age is known to lead to profound morphological and functional alterations. Here, we provide functional evidence—using whole-cell recording—that NO signaling modulates not only glutamatergic but also GABAergic synaptic transmission in the mouse hippocampus during the early postnatal period. We identified the precise subcellular localization of key elements of the underlying molecular cascade using immunohistochemistry at the light—and electron microscopic levels. As predicted by these morpho-functional data, multineuron calcium imaging in acute slices revealed that this NO-signaling machinery is involved also in the control of synchronous network activity patterns. We suggest that the retrograde NO-signaling system is ideally suited to fulfill a general presynaptic regulatory role and may effectively fine-tune network activity during early postnatal development, while GABAergic transmission is still depolarizing

    Reducing global air pollution: the scope for further policy interventions

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    Over the last decades, energy and pollution control policies combined with structural changes in the economy decoupled emission trends from economic growth, increasingly also in the developing world. It is found that effective implementation of the presently decided national pollution control regulations should allow further economic growth without major deterioration of ambient air quality, but will not be enough to reduce pollution levels in many world regions. A combination of ambitious policies focusing on pollution controls, energy and climate, agricultural production systems and addressing human consumption habits could drastically improve air quality throughout the world. By 2040, mean population exposure to PM2.5 from anthropogenic sources could be reduced by about 75% relative to 2015 and brought well below the WHO guideline in large areas of the world. While the implementation of the proposed technical measures is likely to be technically feasible in the future, the transformative changes of current practices will require strong political will, supported by a full appreciation of the multiple benefits. Improved air quality would avoid a large share of the current 3–9 million cases of premature deaths annually. At the same time, the measures that deliver clean air would also significantly reduce emissions of greenhouse gases and contribute to multiple UN sustainable development goals
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