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Aufsatz
Fluoropyrimidines trigger decay of hypomodified tRNA in yeast
(2024-06-10)
Therapeutic fluoropyrimidines 5-fluorouracil (5-FU) and 5-fluorocytosine (5-FC) are in long use for treatment of human cancers and severe invasive fungal infections, respectively. 5-Fluorouridine triphosphate represents a bioactive metabolite of both drugs and is incorporated into target cells’ RNA. Here we use the model fungus Saccharomyces cerevisiae to define fluorinated tRNA as a key mediator of 5-FU and 5-FC cytotoxicity when specific tRNA methylations are absent. tRNA methylation deficiency caused by loss of ...
Aufsatz
Optimal photoelectron circular dichroism of a model chiral system
(2024-06-03)
We optimize the internuclear geometry and electronic structure of a model chiral system to achieve a maximal photoelectron circular dichroism (PECD) in its one-photon ionization by circularly polarized light. The electronic structure calculations are performed by the single center method, while the optimization is done using quantum alchemy employing a Taylor series expansion. Thereby, the effect of bond lengths and uncompensated charge distributions on the chiral response of the model is investigated theoretically ...
Aufsatz
At the limits of bisphosphonio-substituted stannylenes
(2023-12-13)
Donor stabilization of Sn(II) and Pb(II) halides with 1,1’-ferrocenylene bridged bisphosphanes has been explored for Fe(C₅H₄P(C6H₅)₂)₂ (dppf), and Fe(C₅H₄PH(C₄H9))₂. These bisphosphanes are reacted with SnBr₂ and PbCl₂ with and without additional Lewis acid (AlCl₃) forming acyclic and cyclic donor adducts from which the latter represent bisphosphoniotetrylenes. Since dynamic exchange in solution is observed, characterization includes solution and solid-state NMR in addition to SC-XRD, amended by DFT calculations.
Aufsatz
Improving acid-stressed anaerobic digestion processes with biochar towards a combined biomass and carbon management system
(2024-03-06)
Interest in biochar as an additive to enhance anaerobic digestion (AD) has grown in the context of biomass cascading use and the 2050 net-zero goal. However, few studies have investigated the effects of biochar on AD from a biochar production perspective, including biomass feedstocks and pyrolysis temperatures. To valorise biomass and better understand the mechanisms and environmental implications of using biochar in AD, this study investigated the effects of distinct biochar types on AD under acid stress-induced ...
Aufsatz
Personal communication as a strategy to improve the quality of household organic waste – Does it work? results from a quasi-experimental study in Northern Hesse, Germany
(2024-04-22)
Household organic waste has great potential for closing nutrient cycles in agriculture. This requires proper waste separation by households. Personal communication at the doorstep potentially improves household waste separation behaviour but it is expensive and findings from existing research are mixed. Based on results of previous studies and from a quasi-experiment with non-equivalent groups design in two German municipalities, this paper argues that efficiency of personal communication depends on its context. It ...
Aufsatz
Integration and evaluation of the high-precision MotionCam-3D into a 3D thermography system
(2024-06-04)
Infrared thermal imaging enables fast, accurate and non-contact measurement of temperature distributions. However, 2D representations of 3D objects often require several images to provide significant information. For such cases, 3D thermograms allow a quick temporal and spatial analysis. In this paper, the integration of an industrial high-precision 3D sensor into a 3D thermography system is presented. The performances of the existing and new systems are assessed and compared by analyzing 3D thermograms of an ...