Publications by authors named "H Manninen"
Carbonaceous aerosols (CA), composed of black carbon (BC) and organic matter (OM), significantly impact the climate. Light absorption properties of CA, particularly of BC and brown carbon (BrC), are crucial due to their contribution to global and regional warming. We present the absorption properties of BC (b) and BrC (b) inferred using Aethalometer data from 44 European sites covering different environments (traffic (TR), urban (UB), suburban (SUB), regional background (RB) and mountain (M)).
View Article and Find Full Text PDFThere is a body of evidence that ultrafine particles (UFP, those with diameters ≤ 100 nm) might have significant impacts on health. Accordingly, identifying sources of UFP is essential to develop abatement policies. This study focuses on urban Europe, and aims at identifying sources and quantifying their contributions to particle number size distribution (PNSD) using receptor modelling (Positive Matrix Factorization, PMF), and evaluating long-term trends of these source contributions using the non-parametric Theil-Sen's method.
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- Brown carbon (BrC) is a type of organic aerosol that absorbs light in the UV-Vis spectrum, influencing climate, but its full effects are not well understood due to limited knowledge on its chemistry and atmospheric behavior over time.
- This study focused on measuring BrC in particulate matter from winter emissions in Helsinki, specifically in areas influenced by wood combustion, using advanced techniques to analyze its sources, chemical composition, and the extent of light absorption.
- Findings indicated that BrC significantly contributed to light absorption, especially in residential areas, with biomass burning being the primary source, while the research also highlighted variances in absorption characteristics and the uncertainties related to measuring these properties.
Article Synopsis
- * The study found that particle formation rates due to ion-induced processes are stable across temperature changes, while neutral particle formation rates increase significantly when temperatures drop from +10 °C to -10 °C.
- * Despite higher ionization rates, the formation of charged clusters is unlikely to be enhanced in upper tropospheric conditions; instead, neutral nucleation is expected to dominate, with humidity having little effect unless extremely low.
Pretreatment with a dual antiplatelet and anticoagulant (APAC) reduces ischemia-reperfusion injury in a mouse model of temporary middle cerebral artery occlusion-implications for neurovascular procedures.
Acta Neurochir (Wien)
March 2024
Background: Several neurovascular procedures require temporary occlusion of cerebral arteries, leading to ischemia of unpredictable length, occasionally causing brain infarction. Experimental models of cerebral ischemia-reperfusion injury have established that platelet adhesion and coagulation play detrimental roles in reperfusion injury following transient cerebral ischemia. Therefore, in a model of cerebral ischemia-reperfusion injury (IRI), we investigated the therapeutic potential of a dual antiplatelet and anticoagulant (APAC) heparin proteoglycan mimetic which is able to bind to vascular injury sites.
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