Due to special properties, nano-TiO2 will interact with heavy metals and other pollutants in water, thus affecting the environmental behavior and ecotoxicity of these pollutants. However, the exact... Show moreDue to special properties, nano-TiO2 will interact with heavy metals and other pollutants in water, thus affecting the environmental behavior and ecotoxicity of these pollutants. However, the exact manner in which nano-TiO2 affects the bioaccumulation mechanisms of heavy metals is still unclear now. In the present study, quantitative structure bioaccumulation relationship (QSBAR) models were established to explore the relationships between physicochemical parameters of heavy metals and their accumulation in Daphnia magna in the absence and presence of nano-TiO2 at low metal exposure concentrations. The results showed that different physicochemical parameters affected the bioaccumulation of metals in Daphnia magna. The metal accumulation could be described by means of a Comprehensive Parameter composed of seven parameters, i.e., atomic number (AN), relative atomic weight (AW), atomic radius (AR), atomic ionization potential (AN/ΔIP), covalent index (X2r), second ionization energy (I2) and electrochemical potential (E0), in the absence of nano-TiO2, whereas the metal accumulation increased with the increase in Van Der Waals radius (rw) of metals in the presence of nano-TiO2. It was demonstrated that the bioaccumulation mechanism of the metals to Daphnia magna changed in the presence of nano-TiO2. Moreover, the bioaccumulation of more than 85% of the metals increased in the presence of nano-TiO2, but it increased differently for different metals. The present study provides an alternative approach to understand the mechanism of heavy metal bioaccumulation at low metal exposure concentrations and the effect of nano-TiO2 on metal bioaccumulation. Show less
Zhang, C.; Hu, M.; Meide, M. van der; Di Maio, F.; Yang, X.; Gao, X.; ... ; Li, C. 2023
The aim of this thesis is to develop image processing solutions that enable the fully automatic pre-operative planning of aorta-related procedures, such as Trans-catheter aortic valve... Show moreThe aim of this thesis is to develop image processing solutions that enable the fully automatic pre-operative planning of aorta-related procedures, such as Trans-catheter aortic valve replacement and aorta dilatation diagnosis. Hence, the objectives of this thesis are as follows: 1. To fully automatically quantify the aorto-iliac vascular access route, including the aortic root by image processing methods in CTA. 2. To broaden the scope of automatic methods into the detection of aorta dilatation. 3. To integrate the automatic quantification methods into applications which allow manual interactions and the calculation of clinically relevant parameters. 4. To demonstrate the accuracy and feasibility of the fully automatic planning and quantification methods in different patient cohorts. Show less