@article{KraftQuaysonKellner2024, author = {Kraft, Sarah Katharina and Quayson, Matthew and Kellner, Florian}, title = {Assessing the German Act on Corporate Due Diligence Obligations in Supply Chains: a perspective from the smallholder cocoa farmer}, series = {Frontiers in Sustainability}, volume = {5}, journal = {Frontiers in Sustainability}, doi = {10.3389/frsus.2024.1376619}, year = {2024}, abstract = {This research examines the potential outputs, outcomes, and impacts of the German Act on Corporate Due Diligence Obligations in Supply Chains (LkSG) on the smallholder cocoa farmers in West Africa. The study primarily relies on a literature review and an impact pathway to conduct a systematic analysis to identify the potential effects of the LkSG on smallholder cocoa farmers. The findings indicate that some, but not all of the risks addressed by the LkSG align with those faced by smallholder cocoa farmers and their families. Additionally, the research also reveals weaknesses, particularly in managing environmental risks, which the LkSG does not adequately cover. Our findings show that in the short- and medium-term, the LkSG has no potential effects on smallholder cocoa farmers. Furthermore, the potential positive impacts of the law on smallholder cocoa farmers will take a long time to realize, as the LkSG considers primarily tier-1 suppliers. Companies in Germany might reassess their supply chains to strive for an LkSG-risk-free supply chain, which could in the long term have sustained impacts on smallholder cocoa farmers. However, we recommend a comprehensive risk analysis of the cocoa supply chain to enhance the human rights of cocoa farmers.}, language = {en} } @article{WohlschlaegerVersenLoederetal.2024, author = {Wohlschl{\"a}ger, Maximilian and Versen, Martin and L{\"o}der, Martin G. J. and Laforsch, Christian}, title = {Identification of different plastic types and natural materials from terrestrial environments using fluorescence lifetime imaging microscopy.}, series = {Analytical and Bioanalytical Chemistry}, journal = {Analytical and Bioanalytical Chemistry}, doi = {10.1007/s00216-024-05305-w}, year = {2024}, abstract = {Environmental pollution by plastics is a global issue of increasing concern. However, microplastic analysis in complex environmental matrices, such as soil samples, remains an analytical challenge. Destructive mass-based methods for microplastic analysis do not determine plastics' shape and size, which are essential parameters for reliable ecological risk assessment. By contrast, nondestructive particle-based methods produce such data but require elaborate, time-consuming sample preparation. Thus, time-efficient and reliable methods for microplastic analysis are needed. The present study explored the potential of frequency-domain fluorescence lifetime imaging microscopy (FD-FLIM) for rapidly and reliably identifying as well as differentiating plastics and natural materials from terrestrial environments. We investigated the fluorescence spectra of ten natural materials from terrestrial environments, tire wear particles, and eleven different transparent plastic granulates <5 mm to determine the optimal excitation wavelength for identification and differentiation via FD-FLIM under laboratory conditions. Our comparison of different excitation wavelengths showed that 445 nm excitation exhibited the highest fluorescence intensities. 445 nm excitation was also superior for identifying plastic types and distinguishing them from natural materials from terrestrial environments with a high probability using FD-FLIM. We could demonstrate that FD-FLIM analysis has the potential to contribute to a streamlined and time-efficient direct analysis of microplastic contamination. However, further investigations on size-, shape-, color-, and material-type detection limitations are necessary to evaluate if the direct identification of terrestrial environmental samples of relatively low complexity, such as a surface inspection soil, is possible.}, language = {en} } @article{WohlschlaegerVersenLoederetal.2024, author = {Wohlschl{\"a}ger, Maximilian and Versen, Martin and L{\"o}der, Martin G. J. and Laforsch, Christian}, title = {A promising method for fast identification of microplastic particles in environmental samples: A pilot study using fluorescence lifetime imaging microscopy}, series = {Heliyon}, volume = {10}, journal = {Heliyon}, number = {3}, doi = {10.1016/j.heliyon.2024.e25133}, year = {2024}, abstract = {Microplastic pollution of the environment has been extensively studied, with recent studies focusing on the prevalence of microplastics in the environment and their effects on various organisms. Identification methods that simplify the extraction and analysis process to the point where the extraction can be omitted are being investigated, thus enabling the direct identification of microplastic particles. Currently, microplastic samples from environmental matrices can only be identified using time-consuming extraction, sample processing, and analytical methods. Various spectroscopic methods are currently employed, such as micro Fourier-transform infrared, attenuated total reflectance, and micro Raman spectroscopy. However, microplastics in environmental matrices cannot be directly identified using these spectroscopic methods. Investigations using frequency-domain fluorescence lifetime imaging microscopy (FD-FLIM) to identify and differentiate plastics from environmental materials have yielded promising results for directly identifying microplastics in an environmental matrix. Herein, two artificially prepared environmental matrices that included natural soil, grass, wood, and high-density polyethylene were investigated using FD-FLIM. Our first results showed that we successfully identified one plastic type in the two artificially prepared matrices using FD-FLIM. However, further research must be conducted to improve the FD-FLIM method and explore its limitations for directly identifying microplastics in environmental samples.}, language = {en} } @article{ManiyattuGeegyWohlschlaegeretal.2023, author = {Maniyattu, Georgekutty Jose and Geegy, Eldho and Wohlschl{\"a}ger, Maximilian and Leiter, Nina and Versen, Martin and Laforsch, Christian}, title = {Multilayer Perceptron Development to Identify Plastics Using Fluorescence Lifetime Imaging Microscopy}, series = {EDFA Technical Articles}, volume = {25}, journal = {EDFA Technical Articles}, number = {3}, doi = {10.31399/asm.edfa.2023-3.p031}, pages = {31 -- 37}, year = {2023}, abstract = {Existing plastic analysis techniques such as Fourier transform infrared spectroscopy and Raman spectroscopy are problematic because samples must be anhydrous and identification can be hindered by additives. This article describes a new approach that has been successfully demonstrated in which plastics can be classified by neural networks that are trained, validated, and tested by frequency domain fluorescence lifetime imaging microscopy measurements.}, language = {en} } @article{KraftQuaysonKellner2024, author = {Kraft, Sarah Katharina and Quayson, Matthew and Kellner, Florian}, title = {Assessing the German Act on Corporate Due Diligence Obligations in Supply Chains: a perspective from the smallholder cocoa farmer}, series = {Frontiers in Sustainability}, volume = {5}, journal = {Frontiers in Sustainability}, doi = {10.3389/frsus.2024.1376619}, year = {2024}, abstract = {This research examines the potential outputs, outcomes, and impacts of the German Act on Corporate Due Diligence Obligations in Supply Chains (LkSG) on the smallholder cocoa farmers in West Africa. The study primarily relies on a literature review and an impact pathway to conduct a systematic analysis to identify the potential effects of the LkSG on smallholder cocoa farmers. The findings indicate that some, but not all of the risks addressed by the LkSG align with those faced by smallholder cocoa farmers and their families. Additionally, the research also reveals weaknesses, particularly in managing environmental risks, which the LkSG does not adequately cover. Our findings show that in the short- and medium-term, the LkSG has no potential effects on smallholder cocoa farmers. Furthermore, the potential positive impacts of the law on smallholder cocoa farmers will take a long time to realize, as the LkSG considers primarily tier-1 suppliers. Companies in Germany might reassess their supply chains to strive for an LkSG-risk-free supply chain, which could in the long term have sustained impacts on smallholder cocoa farmers. However, we recommend a comprehensive risk analysis of the cocoa supply chain to enhance the human rights of cocoa farmers.}, language = {en} } @article{SchwarzOrtlerLindner2024, author = {Schwarz, B. and Ortler, M. C. and Lindner, J. A.}, title = {Rotational speed change and reverse mixing to avoid baffles in dispersing processes}, series = {Chemical Engineering Research and Design}, volume = {206}, journal = {Chemical Engineering Research and Design}, doi = {10.1016/j.cherd.2024.05.004}, pages = {302 -- 309}, year = {2024}, abstract = {Stirring is used for mass and heat transfer, particle suspending or similar processes. It is commonly conducted in a steady operation mode. This paper targets on performing the stirring process dynamically by reversing the rotation direction to introduce additional turbulences and hence accelerating the dispersing processes. The power introduced into the fluid as well as mixing kinetics performing dynamic mixing were studied based on the rotational acceleration, blade pitch angle, liquid volume and duration of the rotational speed direction interval for a vessel equipped with a turbine agitator with and without baffles. Experiments show that baffles are not necessary if reverse mixing is performed at a specific frequency.}, language = {en} } @article{RosiereSantosSilveiraBragaetal.2021, author = {Rosi{\`e}re, C. A. and Santos, J. O. S. and Silveira Braga, F. and Hensler, Ana-Sophie and Rolim, V. K. and Bekker, A.}, title = {Multiple Hydrothermal Iron-Formation Upgrading Events in Southeastern S{\~a}o Francisco Craton}, series = {The Journal of Geology}, volume = {129}, journal = {The Journal of Geology}, number = {3}, publisher = {The University of Chicago Press}, address = {Chicago}, doi = {10.1086/715242}, pages = {283 -- 296}, year = {2021}, abstract = {Large-scale, hypogene iron mineralization systems developed recurrently in the S{\~a}o Francisco craton in association with two orogenies. During the ca. 2.1-2.0 Ga Trans-Amazonian orogeny, low-temperature and low-to-moderate-salinity metamorphic fluids resulted in carbonatization-related iron enrichment of the early Paleoproterozoic Cau{\^e} Iron Formation (IF) of the Minas Supergroup (MSG) as well as short-distance iron mobilization. Monazite from the iron-oxide veins yielded a SHRIMP 232Th/208Pb date corresponding to fluid circulation coeval with the migmatization of the Archean tonalite-trondhjemite-granodiorite crust. During the Ediacaran to Cambrian Brasiliano orogeny, when the S{\~a}o Francisco craton was consolidated in its present configuration, hydrothermal fluids repeatedly mineralized the Cau{\^e} IF and the younger IFs of the lower Espinha{\c{c}}o Supergroup. Far-field hydrothermal alteration associated with distinct Fe mineralization episodes widely affected Meso- to Neoproterozoic sequences as well as Archean to Paleoproterozoic terranes of the cratonic core. Circulation of hydrothermal fluids during the Brasiliano orogeny caused desilicification, iron mobilization, and widespread alteration of the rocks. The alteration events are dated with monazite and xenotime intergrown with hematite, anatase, and recrystallized rims of detrital zircons from interlayered quartzites and of igneous zircons from pegmatites, granites, acidic volcanic rocks, and orthogneisses, yielding U-Pb dates between 542 and 493 Ma. U-Pb dates point to five Cambrian hydrothermal events from the waning stages to the aftermath of the Brasiliano orogeny. These hydrothermal fluid circulation events correspond to the emplacement ages of four granite suites and pegmatites that lasted from the final stages of the collision to the collapse of the Ara{\c{c}}ua{\´i}-West Congo orogen. Episodic circulation of fluids continued for approximately 2 billion years after IF deposition on the eastern S{\~a}o Francisco craton with the formation of high-grade iron ore deposits and resetting of the IF trace-element inventory.}, language = {en} } @article{FischerMichalkHardtetal.2024, author = {Fischer, Markus and Michalk, Wibke and Hardt, Cornelius and Bogenberger, Klaus}, title = {Bill It Right: Evaluating Public Charging Station Usage Behavior under the Presence of Different Pricing Policies}, series = {World Electric Vehicle Journal}, volume = {15}, journal = {World Electric Vehicle Journal}, number = {4}, doi = {10.3390/wevj15040175}, year = {2024}, abstract = {This study investigates for the first time how public charging infrastructure usage differs under the presence of diverse pricing models. About 3 million charging events from different European countries were classified according to five different pricing models (cost-free, flat-rate, time-based, energy-based, and mixed) and evaluated using various performance indicators such as connection duration; transferred energy volumes; average power; achievable revenue; and the share of charging and idle time for AC, DC, and HPC charging infrastructure. The study results show that the performance indicators differed for the classified pricing models. In addition to the quantitative comparison of the performance indicators, a Kruskal-Wallis one-way analysis of variance and a pairwise comparison using the Mann-Whitney-U test were used to show that the data distributions of the defined pricing models were statistically significantly different. The results are discussed from various perspectives on the efficient design of public charging infrastructure. The results show that time-based pricing models can improve the availability of public charging infrastructure, as the connection duration per charging event can be roughly halved compared to other pricing models. Flat-rate pricing models and AC charging infrastructure can support the temporal shift of charging events, such as shifting demand peaks, as charging events usually have several hours of idle time per charging process. By quantifying various performance indicators for different charging technologies and pricing models, the study is relevant for stakeholders involved in the development and operation of public charging infrastructure.}, language = {en} } @article{SchmiedtWeiss2024, author = {Schmiedt, Anja Bettina and Weiß, Christian}, title = {The pair correlation function of multi-dimensional low-discrepancy sequences with small stochastic error terms}, series = {Journal of Number Theory}, volume = {259}, journal = {Journal of Number Theory}, doi = {10.1016/j.jnt.2023.12.011}, pages = {422 -- 437}, year = {2024}, abstract = {In any dimension d≥2, there is no known example of a low-discrepancy sequence which possesses Poisssonian pair correlations. This is in some sense rather surprising, because low-discrepancy sequences always have β-Poissonian pair correlations for all 0<β<1/d and are therefore arbitrarily close to having Poissonian pair correlations (which corresponds to the case β=1/d). In this paper, we further elaborate on the closeness of the two notions. We show that d-dimensional Kronecker sequences for badly approximable vectors α→ with an arbitrary small uniformly distributed stochastic error term generically have β=1/d-Poissonian pair correlations.}, language = {en} } @article{AslanKubik2024, author = {Aslan, Alp and Kubik, Veit}, title = {Buildup and Release from Proactive Interference: The Forward Testing Effect in Children's Spatial Memory}, series = {Journal of Experimental Child Psychology}, volume = {240}, journal = {Journal of Experimental Child Psychology}, publisher = {Elsevier}, doi = {10.1016/j.jecp.2023.105838}, year = {2024}, abstract = {Previous work has indicated that testing can enhance memory for subsequently studied new information by reducing proactive interference from previously studied information. Here, we examined this forward testing effect in children's spatial memory. Kindergartners (5-6 years) and younger (7-8 years) and older (9-10 years) elementary school children studied four successively presented 3 x 3 arrays, each composed of the same 9 objects. The children were asked to memorize the locations of the objects that differed across the four arrays. Following presentation of each of the first three arrays, memory for the object locations of the respective array was tested (testing condition) or the array was re-presented for additional study (restudy condition). Results revealed that testing Arrays 1 to 3 enhanced children's object location memory for Array 4 relative to restudying. Moreover, children in the testing condition were less likely to confuse Array 4 locations with previous locations, suggesting that testing reduces the buildup of proactive interference. Both effects were found regardless of age. Thus, the current findings indicate that testing is an effective means to resolve proactive interference and, in this way, to enhance children's learning and remembering of spatial information even before the time of school entry.}, language = {en} }