Publications by authors named "N Heeb"

High production rates of chlorinated paraffins (CPs) and their widespread use resulted in a global contamination. Since 2017, short-chain CPs (SCCPs, C-C) are listed as persistent organic pollutants (POPs) in the Stockholm Convention. Technical CP mixtures contain hundreds of homologues and side products such as chlorinated olefins (COs), diolefins (CdiOs) and triolefins (CtriOs).

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Chlorinated paraffins (CPs) are complex mixtures of polychlorinated -alkanes with multiple carbon- (C-, = 9-30) and chlorine homologues (Cl-, = 3-18). The mass spectrometric analysis of CPs is time-consuming and challenging, especially when interferences between CPs, their transformation products, or from the matrix are numerous. These analytical challenges and the lack of appropriate and accessible data evaluation tools are obstacles to their analysis.

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Jet engines are important contributors to global CO emissions and release enormous numbers of ultrafine particles into different layers of the atmosphere. As a result, aviation emissions are affecting atmospheric chemistry and promote contrail and cloud formation with impacts on earth's radiative balance and climate. Furthermore, the corelease of nanoparticles together with carcinogenic polycyclic aromatic hydrocarbons (PAHs) affects air quality at airports.

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Article Synopsis
  • The study investigates human exposure to chlorinated paraffins (CPs) in sewage sludge from a Swiss wastewater treatment plant (WWTP) over several years, focusing on the regulation of short-chain CPs (SCCPs) since 2017 as persistent organic pollutants.
  • Using advanced liquid chromatography mass spectrometry, researchers detected thousands of ions related to CPs and chlorinated olefins (COs), identifying a range of homologues and their distributions in the sludge.
  • Results show a significant decrease in the levels of SCCPs (84%) and other chlorinated compounds from 1993 to 2020, indicating shifts in the presence of banned substances and suggesting that higher-chlorinated SCCPs have been replaced by
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Objective: Target depth, defined by the z-coordinate in the dorsoventral axis relative to the anterior commissure-posterior commissure axial plane of the MR-guided focused ultrasound (MRgFUS) lesion, is considered to be critical for tremor improvement and the occurrence of side effects such as gait impairment. However, although different z-coordinates are used in the literature, there are no comparative studies available with information on optimal lesion placement. This study aimed to compare two different MRgFUS lesion targets (z = +2 mm vs z = 0 mm) regarding efficacy and safety outcomes.

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