11 research outputs found
Environmental risks of car tire microplastic particles and other road runoff pollutants
Tire wear represents a large source of microplastic entering the aquatic environment, however little is known about its environmental risks. Here, we provide the first assessment of the environmental risks of pollution with tire wear microplastic particles (TWP) and associated organic micropollutants present in road runoff in Europe, in one go. Besides microplastic TWP, the assessment focused on priority substances as defined by the Water Framework Directive (WFD). In addition, several other pollutants (mercaptobenzothiazole, tolyltriazole, diisodecyl phthalate and hexa (methoxymethyl)melamine) were included. The risk assessment comprised a hazard identification (selection of traffic related substances), an assessment of exposure (Predicted Environmental Concentrations, PECs), based on estimated and measured values, effect assessment (selection of Predicted No Effect Concentrations, PNECs, and effect values) and a risk characterization (PEC/PNEC and Species Sensitivity Distributions (SSDs)). Whole Effluent Toxicity (WET)-tests on samples taken from road runoff, surface water and sediment were conducted as a retrospective approach to support the risk assessment. We demonstrate that risks exist for TWP and for several TWP-associated chemical substances in surface water and sediment. In addition, WET-tests of the runoff samples showed significant dose-related effects for algae. However, WET-tests of surface water showed no significant toxic effects. The present study provides opportunities to protect the quality of European waters from complex road runoff pollution, focusing on TWP microplastic, their associated WFD priority substances and other hazardous substances
70 GHz InGaAs metal-semiconductor-metal photodetectors for polarisation-insensitive operation
Greenhouse gas emissions in the Netherlands 1990–2015 : National Inventory Report 2017
Total greenhouse gas (GHG) emissions from the Netherlands in 2015 increased by approximately 4%, compared with 2014 emissions. This increase was mainly the result of the increased electricity production in coal fired plants compared to 2014. Furthermore fuel combustion in all sectors was increased as the winter of 2015 was less mild as the one in 2014. In 2015, total GHG emissions (including indirect CO2 emissions and excluding emissions from Land use, land use change and forestry (LULUCF)) in the Netherlands amounted to 195.2 Tg CO2 eq. This is approximately 12.5% below the emissions in the base year2 (223.1 Tg CO2 eq). CO2 emission have increased above the level in the base year 1990 in 2015 (+ 1.5%). This increase was offset by the reduction in the emissions since 1990 of methane, nitrous oxide and fluorinated gases (CH4, N2O and F-gases). This report documents the Netherlands’ 2017 annual submission of its greenhouse gas emissions inventory in accordance with the 2006 IPCC Guidelines for National Greenhouse Gas Inventories (IPCC, 2006) provided by the United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto Protocol and the European Union’s Greenhouse Gas Monitoring Mechanism. The report includes explanations of observed trends in emissions; an assessment of the sources with the highest contribution to the national emissions (key sources) and the uncertainty in their emissions; an itemization of methods, data sources and emission factors (EFs) applied; and a description of the quality assurance system and the verification activities performed on the data
HLA-DR–Mediated Signals for Hematopoiesis and Induction of Apoptosis Involve But Are Not Limited to a Nitric Oxide Pathway
High Target Homology Does Not Guarantee Inhibition: Aminothiazoles Emerge as Inhibitors of Plasmodium falciparum
In this study, we identified three novel compound classes
with
potent activity against Plasmodium falciparum, the most dangerous human malarial parasite. Resistance of this
pathogen to known drugs is increasing, and compounds with different
modes of action are urgently needed. One promising drug target is
the enzyme 1-deoxy-d-xylulose-5-phosphate synthase (DXPS)
of the methylerythritol 4-phosphate (MEP) pathway for which we have
previously identified three active compound classes against Mycobacterium tuberculosis. The close structural
similarities of the active sites of the DXPS enzymes of P. falciparum and M. tuberculosis prompted investigation of their antiparasitic action, all classes
display good cell-based activity. Through structure–activity
relationship studies, we increased their antimalarial potency and
two classes also show good metabolic stability and low toxicity against
human liver cells. The most active compound 1 inhibits
the growth of blood-stage P. falciparum with an IC50 of 600 nM. The results from three different
methods for target validation of compound 1 suggest no
engagement of DXPS. All inhibitor classes are active against chloroquine-resistant
strains, confirming a new mode of action that has to be further investigated
High Target Homology Does Not Guarantee Inhibition: Aminothiazoles Emerge as Inhibitors of Plasmodium falciparum
In this study, we identified three novel compound classes
with
potent activity against Plasmodium falciparum, the most dangerous human malarial parasite. Resistance of this
pathogen to known drugs is increasing, and compounds with different
modes of action are urgently needed. One promising drug target is
the enzyme 1-deoxy-d-xylulose-5-phosphate synthase (DXPS)
of the methylerythritol 4-phosphate (MEP) pathway for which we have
previously identified three active compound classes against Mycobacterium tuberculosis. The close structural
similarities of the active sites of the DXPS enzymes of P. falciparum and M. tuberculosis prompted investigation of their antiparasitic action, all classes
display good cell-based activity. Through structure–activity
relationship studies, we increased their antimalarial potency and
two classes also show good metabolic stability and low toxicity against
human liver cells. The most active compound 1 inhibits
the growth of blood-stage P. falciparum with an IC50 of 600 nM. The results from three different
methods for target validation of compound 1 suggest no
engagement of DXPS. All inhibitor classes are active against chloroquine-resistant
strains, confirming a new mode of action that has to be further investigated