Satellite evidence for changes in the NO2 weekly cycle over large cities.

Anthropogenic activities, by far the largest source of NOx into the atmosphere, induce a weekly cycle of NO2 abundances in cities. Comprehensive analysis of the 2005-2017 OMI NO2 dataset reveals significant weekly cycles in 115 of the 274 cities considered. These results are corroborated by a full year of high-resolution TROPOMI NO2 observations. The OMI dataset permits us to identify trends in the weekly cycle resulting from NOx emissions changes. The data show a clear weakening of the weekly cycle over European and U.S. cities, an evolution attributed to the decline in anthropogenic emissions and the resulting growing importance of background NO2, whereas NO2 lifetime changes also play a minor role. In particular, the Sunday NO2 columns averaged over all U.S. cities are found to increase, relative to the weekly average, from 0.72 during 2005-2007 to 0.88 in 2015-2017. The opposite tendency is recorded in regions undergoing rapid emission growth. Multiyear simulations over the U.S. and the Middle East using the chemistry-transport model MAGRITTEv1.1 succeed in capturing the observed weekly cycles over the largest cities, as well as the observed long-term trends in the weekly cycle.

Quantification of nitrogen oxides emissions from build-up of pollution over Paris with TROPOMI.

Nitrogen dioxide (NO2) is a regulated air pollutant that is of particular concern in many cities, where concentrations are high. Emissions of nitrogen oxides to the atmosphere lead to the formation of ozone and particulate matter, with adverse impacts on human health and ecosystems. The effects of emissions are often assessed through modeling based on inventories relying on indirect information that is often outdated or incomplete. Here we show that NO2 measurements from the new, high-resolution TROPOMI satellite sensor can directly determine the strength and distribution of emissions from Paris. From the observed build-up of NO2 pollution, we find highest emissions on cold weekdays in February 2018, and lowest emissions on warm weekend days in spring 2018. The new measurements provide information on the spatio-temporal distribution of emissions within a large city, and suggest that Paris emissions in 2018 are only 5-15% below inventory estimates for 2011-2012, reflecting the difficulty of meeting NOx emission reduction targets.

Acute and persistent platelet and coagulant activities in atherothrombosis.

The potential relevance of murine atherothrombosis models for understanding human disease has been debated in the past. Despite this, in the last decade, many thrombosis studies with atherogenic Apoe(-/-) mice have been performed, which provide novel insight into the molecular mechanisms by which platelet and coagulation processes accomplish acute thrombus formation after plaque disruption in vivo. Support for these mechanisms has come from whole blood flow perfusion studies over plaque material in vitro, which are also reviewed in this study. The main plaque-derived triggers for thrombus formation appear to be collagen and tissue factor, next to bioactive mediators such as prostaglandin E2. The atherothrombotic process relies on collagen- and ADP-receptor-induced platelet activation as well as on thrombin/fibrin generation via the extrinsic and intrinsic coagulation pathways. Less is known of the persistent effects of a thrombus on atherosclerosis progression, but evidence suggests roles herein of activated platelets and ongoing thrombin generation.

Effect of flat insoles with different Shore A values on posture stability in diabetic neuropathy.

The objective of the study was to determine whether insoles with a low Shore A value (15 degrees) as prescribed for patients with a diabetic neuropathy have a negative effect on posture stability because these insoles may reduce somatosensory input under the feet. It was conducted in the Center for Rehabilitation, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands The study was observational and conducted on 30 diabetic patients (aged 37 - 82 years) with a neuropathy. Posture stability (body sway) was assessed in a shoe without insole, on a flat insole with a low Shore A value (15 degrees) and on a flat insole with a higher Shore A value (30 degrees). These assessments were done under four different conditions: (1) eyes open, no dual-task, (2) eyes closed, no dual-task, (3) eyes open, dual-task (mental arithmetic) and (4) eyes closed, dual-task. Additionally 10 healthy controls (aged 27 - 51 years) were assessed similarly. A significantly higher root-mean-square (rms) value of the anterior-posterior velocity, V(y), was found in patients compared with controls (3.4 cm/s vs. 1.2 cm/s, p < 0.05). Also a significant difference in rms value of the anterior-posterior velocity, V(y), was found between eyes open and eyes closed (1.9 cm/s vs. 2.7 cm/s, p < 0.05). No significant effects were found for insoles or dual tasks for the total group. In diabetic patients no significant effect was found of insoles on posture stability. The effect of closed eyes on posture stability was significantly larger for diabetic patients compared to controls. It was found that prescribing insoles with a low Shore A value (15 degrees), compared to insoles with a higher Shore A value (30 degrees) has no significant negative effect on posture stability in patients with a diabetic neuropathy.