Transregional Collaborative Research Centre Research Articles

Ground-based remote sensing of aerosol properties using high-resolution infrared emission and lidar observations in the High Arctic

Abstract. Arctic amplification, the phenomenon that the Arctic is warming faster than the global mean, is still not fully understood. The Transregional Collaborative Research Centre “TRR 172: ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3” program, funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), contributes towards this research topic. For the purpose of measuring aerosol components, a Fourier transform infrared spectrometer (FTIR), for measuring downwelling emission (in operation since 2019), and a Raman lidar are operated at the joint Alfred Wegener Institute for Polar and Marine Research and Paul Emile Victor Institute (AWIPEV) research base in Ny-Ålesund, Spitsbergen (79∘ N, 12∘ E). To carry out aerosol retrieval using measurements from the FTS, the LBLDIS retrieval algorithm, based on a combination of the Line-by-Line Radiative Transfer Model (LBLRTM) and the DIScrete Ordinate Radiative Transfer (DISORT) algorithm, is modified for different aerosol types (dust, sea salt, black carbon, and sulfate), aerosol optical depth (AOD), and effective radius (Reff). Using lidar measurement, an aerosol and cloud classification method is developed to provide basic information about the distribution of aerosols or clouds in the atmosphere and is used as an indicator to perform aerosol or cloud retrievals with the FTS. Therefore, a two-instrument joint-observation scheme is designed and subsequently used on the data measured from 2019 to the present. In order to introduce this measurement technique in detail, an aerosol-only case study is presented using data from 10 June 2020. In the aerosol-only case, the retrieval results show that sulfate is the dominant aerosol throughout the day (τ900cm-1 = 0.007 ± 0.0027), followed by dust (τ900cm-1 = 0.0039 ± 0.0029) and black carbon (τ900cm-1 = 0.0017 ± 0.0007). Sea salt (τ900cm-1 = 0.0012 ± 0.0002), which has the weakest emission ability in the infrared wave band, shows the lowest AOD value. Such proportions of sulfate, dust, and BC also show good agreement with Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2) reanalysis data. Additionally, comparison with a Sun photometer (AErosol RObotic NETwork – AERONET) shows the daily variation in the AOD retrieved from FTS to be similar to that retrieved by Sun photometer. Using this method, long-term observations (from April to August 2020) are retrieved and presented. We find that sulfate is often present in the Arctic; it is higher in spring and lower in summer. Similarly, BC is also frequently observed in the Arctic, with less obvious seasonal variation than sulfate. A BC outburst event is observed each spring and summer. In spring, sulfate and BC are dominant, whereas sea salt and dust are relatively low. In addition, a sea salt enhancement event is observed in summertime, which might be due to the melting of sea ice and emissions from nearby open water. From the retrieved results over a long time period, no clear correlations are found; thus, the aforementioned species can be retrieved independently of one another.

Determination of Machining Parameters for a Specific Adjustment of the Residual Stress Profile by Induction Hardening*

Abstract Within the research work of the Transregional Collaborative Research Center TRR 136, process signatures were determined for processes that generate essentially thermal loading of the component surface layer. These process signatures represent correlations between material modifications (e. g. changes of residual stress, microstructure, hardness profile, etc.) and characteristic values of the material loading. The underlying idea is that the material does not know any processes but only loads caused by processes. In particular, the same loads lead to the same material modifications regardless of the kind of process. A decisive advantage of this concept over conventional approaches is the possibility of calculating the necessary internal material loads backwards on the basis of concrete specifications for the material modifications. If there are additional correlations between internal material loads and process quantities as well as between process quantities and machining parameters, the necessary machining parameters can be determined, too. In this paper, this procedure will be introduced using the example of one-sided induction hardening of cuboidal components made of 42CrMo4. The determination of the process signature by experimental and numerical investigations is described and work for experimental verifications are presented.

New Aspects of Kidney Fibrosis-From Mechanisms of Injury to Modulation of Disease.

Organ fibrogenesis is characterized by a common pathophysiological final pathway independent of the underlying progressive disease of the respective organ. This makes it particularly suitable as a therapeutic target. The Transregional Collaborative Research Center “Organ Fibrosis: From Mechanisms of Injury to Modulation of Disease” (referred to as SFB/TRR57) was hosted from 2009 to 2021 by the Medical Faculties of RWTH Aachen University and the University of Bonn. This consortium had the ultimate goal of discovering new common but also different fibrosis pathways in the liver and kidneys. It finally successfully identified new mechanisms and established novel therapeutic approaches to interfere with hepatic and renal fibrosis. This review covers the consortium's key kidney-related findings, where three overarching questions were addressed: (i) What are new relevant mechanisms and signaling pathways triggering renal fibrosis? (ii) What are new immunological mechanisms, cells and molecules that contribute to renal fibrosis?, and finally (iii) How can renal fibrosis be modulated?

Liver Fibrosis-From Mechanisms of Injury to Modulation of Disease.

The Transregional Collaborative Research Center “Organ Fibrosis: From Mechanisms of Injury to Modulation of Disease” (referred to as SFB/TRR57) was funded for 13 years (2009–2021) by the German Research Council (DFG). This consortium was hosted by the Medical Schools of the RWTH Aachen University and Bonn University in Germany. The SFB/TRR57 implemented combined basic and clinical research to achieve detailed knowledge in three selected key questions: (i) What are the relevant mechanisms and signal pathways required for initiating organ fibrosis? (ii) Which immunological mechanisms and molecules contribute to organ fibrosis? and (iii) How can organ fibrosis be modulated, e.g., by interventional strategies including imaging and pharmacological approaches? In this review we will summarize the liver-related key findings of this consortium gained within the last 12 years on these three aspects of liver fibrogenesis. We will highlight the role of cell death and cell cycle pathways as well as nutritional and iron-related mechanisms for liver fibrosis initiation. Moreover, we will define and characterize the major immune cell compartments relevant for liver fibrogenesis, and finally point to potential signaling pathways and pharmacological targets that turned out to be suitable to develop novel approaches for improved therapy and diagnosis of liver fibrosis. In summary, this review will provide a comprehensive overview about the knowledge on liver fibrogenesis and its potential therapy gained by the SFB/TRR57 consortium within the last decade. The kidney-related research results obtained by the same consortium are highlighted in an article published back-to-back in Frontiers in Medicine.

Cooperative Effects in Heterometallic Complexes

3MET: In this Guest Editorial, M. H. Prosenc, M. M. Kappes, and G. Niedner‐Schatteburg, present the latest work from the transregional collaborative research center 3MET.de founded in 2009 and located at the TU Kaiserslautern (TUK) and at the Karlsruhe Institute of Technology (KIT).

Plasminogen activator inhibitor-1 (PAI-1) is anti-fibrogenic in human inflammatory cardiomyopathy

Abstract Background/Introduction Preclinical data indicate that plasminogen activator inhibitor-1 (PAI-1) is cardioprotective by repressing cardiac fibrosis through TGF-β and plasminogen mediated pathways. In addition it is linked to the recruitment and polarization of non-classical M2 macrophages in cancer. Purpose The role of cardiac PAI-1 in fibrogenesis and macrophage polarization is investigated in patients with dilated cardiomyopathy (DCM) and inflammatory dilated cardiomyopathy (DCMi). Methods We retrospectively analyzed endomyocardial biopsies (EMBs) of patients with DCM (n=27) and DCMi (n=149) for PAI-1 expression, number of activated myofibroblasts and M1/M2 macrophage polarization. Results Patients with high-grade DCMi (DCMi-high, CD3+ lymphocytes >30 cells/mm2) had significantly increased PAI-1 levels compared to DCM and low grade DCMi patients (DCMi-low, CD3+ lymphocytes = 14 - 30 cells/mm2) (15.5±0.4% vs. 1.0±0.1% and 4.0±0.1%, p≤0.001). Elevated PAI-1 expression in DCMi-high subjects was accompanied by a reduced number of alpha smooth muscle actin (α-SMA) positive myofibroblasts and an increased number of CD16+ CD68+ M2 macrophages, indicating anti-fibrogenic and M2 macrophage-favoring properties of PAI-1 in DCMi. Conclusion Our findings give evidence that elevated expression of PAI-1 suppresses cardiac fibrosis and promotes M2 macrophage polarization. Thus, PAI-1 could serve as a potential prognostic biomarker of cardiac fibrosis and inflammation, as well as possible therapeutic target in inflammatory cardiomyopathies. Funding Acknowledgement Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERA-Net on Cardiovascular Diseases (ERA-CVD) of the German Research Foundation (DFG)Transregional Collaborative Research Center “Inflammatory Cardiomyopathy-Molecular Pathogenesis and Therapy”

Cover Feature: Thermally Activated Delayed Fluorescence and Phosphorescence Quenching in Iminophosphonamide Copper and Zinc Complexes (Chem. Eur. J. 61/2021)

The Cover Feature image shows the transfer of samples within our project from Karlsruhe (synthesis and photoluminescence) to Kaiserslautern (step-scan FTIR analysis). The route is adapted to the thermally activated delayed fluorescence (TADF) curve of one sample, which is shown on the lower left. The work took place within a DFG funded transregional collaborative research center (SFB/TRR 88) established between Kaiserslautern and Karlsruhe (3MET). More information can be found in the Full Paper by P. W. Roesky et al. (DOI: 10.1002/chem.202101247).

A variational concept and its experimental calibration for temperature‐induced rate‐dependent phase transformations in steel

AbstractIn forming processes of metals, different physical phenomena are observable which may alter the material properties and behavior severely. These observations can be attributed to changes in the surface layer of the material. This research is a part of the transregional collaborative research center SFB/TRR 136 which deals with surface layer modifications in 42CrMo4 steels and aims to determine process independent correlations between material loads and material modifications. These correlations are called process signatures. The present work is concerned with investigating thermally induced solid‐solid phase transformations in steels. An example of a predominantly thermal process is the induction hardening process. In this process, an initially ferritic‐pearlitic structure is at first heated until reaching a temperature that lies above the temperature at which homogeneous austenite is formed. During this heating process, the steel undergoes diffusion‐driven phase transformations which are heating‐rate‐ and time‐dependent. After sufficiently long incubation, a homogeneous austenitic microstructure is obtained. Then, the specimen temperature is lowered at a very high cooling rate. This invokes high‐temperature rates on the microstructure and results in an austenitic‐martensitic phase transformation, see e.g. [1]. Based on the Principle of the Minimum of the Dissipation Potential (PDMP) as presented in [2], the austenitic‐martensitic transformation has been widely discussed in the context of shape memory alloys. We present a material model which is also able to show the ferritic‐austenitic transformation. The individual phase transitions are modeled using a rate‐ and transformation‐process‐dependent formulation of the dissipation potential. The presented material model is finally tested with numerical simulations.

A comprehensive dataset of vegetation states, fluxes of matter and energy, weather, agricultural management, and soil properties from intensively monitored crop sites in western Germany

Abstract. The development and validation of hydroecological land-surface models to simulate agricultural areas require extensive data on weather, soil properties, agricultural management, and vegetation states and fluxes. However, these comprehensive data are rarely available since measurement, quality control, documentation, and compilation of the different data types are costly in terms of time and money. Here, we present a comprehensive dataset, which was collected at four agricultural sites within the Rur catchment in western Germany in the framework of the Transregional Collaborative Research Centre 32 (TR32) “Patterns in Soil–Vegetation–Atmosphere Systems: Monitoring, Modeling and Data Assimilation”. Vegetation-related data comprise fresh and dry biomass (green and brown, predominantly per organ), plant height, green and brown leaf area index, phenological development state, nitrogen and carbon content (overall > 17 000 entries), and masses of harvest residues and regrowth of vegetation after harvest or before planting of the main crop (> 250 entries). Vegetation data including LAI were collected in frequencies of 1 to 3 weeks in the years 2015 until 2017, mostly during overflights of the Sentinel 1 and Radarsat 2 satellites. In addition, fluxes of carbon, energy, and water (> 180 000 half-hourly records) measured using the eddy covariance technique are included. Three flux time series have simultaneous data from two different heights. Data on agricultural management include sowing and harvest dates as well as information on cultivation, fertilization, and agrochemicals (27 management periods). The dataset also includes gap-filled weather data (> 200 000 hourly records) and soil parameters (particle size distributions, carbon and nitrogen content; > 800 records). These data can also be useful for development and validation of remote-sensing products. The dataset is hosted at the TR32 database (https://www.tr32db.uni-koeln.de/data.php?dataID=1889, last access: 29 September 2020) and has the DOI https://doi.org/10.5880/TR32DB.39 (Reichenau et al., 2020).

Investigations of the Influence of a Superimposed Oscillation on the Fatigue Strength

Within the scope of the transregional collaborative research centre TCRC73, the effects of an oscillation superimposed forming process for the production of a demonstrator component are investigated. Previous studies in this field were limited to a consideration of the process-related parameters such as the influence of the plastic work and the friction or the component-related parameters such as the influence of the surface quality and the mold filling. This research concentrates on the consideration of the mechanical vibration resistance of components that were manufactured superimposed oscillated. For this purpose, Wöhler tests are conducted in which the fatigue strength of superimposed oscillation pre-stretched test samples and oscillation-free pre-stretched test samples are investigated. First, Wöhler curves are generated in the tensile threshold range for tensile samples made out of the steels DC04 and DP600. Subsequently, tensile specimens are pre-stretched superimposed oscillated and oscillation-free. These specimens are subjected to a tensile threshold load until they break. The influence of the superimposed oscillation forming on the long-term fatigue of components is derived from the comparison of the bearable load cycles. Investigations of the microstructure of the specimens are conducted in order to draw conclusions about the influence on the long-term strength.

Investigation of the Influence of an Oscillation Superposition on the Wear Behaviour in an Industrial-like Process

In cold forging processes as well as in sheet-bulk metal forming, vast contact stresses result in severe tool wear and thus in tool failures. In order to achieve a sustainable production, a new manufacturing process is developed within the subproject T06 in the transregional collaborative research centre 73 at the Institute of Forming Technology and Machines (IFUM). In this subproject the influence of an oscillation superposition on a forming process is investigated. The new type of sheet-bulk metal forming (SBMF) process manufactures a component with internal and external gearing. Contact normal stresses and thus tool wear could be reduced by applying an oscillation superposition in the main force flow of the machine. To verify the positive results in other processes, the oscillation method is applied to an industrial-like process based on anchor bolt manufacturing of Fischerwerke GmbH & Co. KG. For this purpose, a representative tool system is developed using numerical simulation. The numerical simulation is also used to investigate resulting local contact stresses and relative sliding velocities. Furthermore, cylinder compression tests with and without oscillation superposition are conducted for the workpiece stainless steel 1.4362 (AISI S32304), in order to qualify the reduction of contact stress.

Electron kinetics at the plasma interface

The most fundamental response of an ionized gas to a macroscopic object is the formation of the plasma sheath. It is an electron depleted space charge region, adjacent to the object, which screens the object's negative charge arising from the accumulation of electrons from the plasma. The plasma sheath is thus the positively charged part of an electric double layer whose negatively charged part is inside the wall. In the course of the Transregional Collaborative Research Center SFB/TRR24 we investigated, from a microscopic point of view, the elementary charge transfer processes responsible for the electric double layer at a floating plasma-wall interface and made first steps towards a description of the negative part of the layer inside the wall. Below we review our work in a colloquial manner, describe possible extensions, and identify key issues which need to be resolved to make further progress in the understanding of the electron kinetics across plasma-wall interfaces.

Thermo-controllable self-assembled structures of single-layer 4, 4″-diamino-p-terphenyl molecules on Au (110)**Project supported by the National Natural Science Foundation of China (Grant Nos. 61390501, 61471337, 61622116, and 51325204), the National Key Scientific Instrument and Equipment Development Project of China (Grant No. 2013YQ1203451), the CAS Hundred Talents Program, the Transregional Collaborative Research Center TRR 61 (Grant No. 21661132006), and the National Supercomputing

Here we report the thermo-controllable self-assembled structures of single-layer 4, 4″-diamino-p-terphenyl (DAT) molecules on Au (110), which are investigated by scanning tunneling microscopy (STM) combined with density functional theory (DFT) based calculations. With the deposition of monolayer DAT molecules on Au (110) and subsequent annealing at 100 °C, all DAT molecules adsorb on a (1 × 5) reconstructed surface with a ladder-like structure. After annealing the sample at about 200 °C, STM images show three distinct domains, including DAT molecules on a (1 × 3) reconstructed surface, dehydrogenated molecules with two hydrogen atoms detached from one amino group (−2H-DAT) on a (1 × 5) reconstructed surface and dehydrogenated molecules with four hydrogen atoms detached from two amino groups (–4H-DAT) on a (1 × 3) reconstructed surface through N–Au bonds. Furthermore, after annealing the sample to 350 °C, STM image shows only one self-assembled structure with −4H-DAT molecules on a (1 × 3) reconstructed surface. Relative STM simulations of different self-assembled structures show excellent agreements with the experimental STM images at different annealing temperatures. Further DFT calculations on the dehydrogenation process of DAT molecule prove that the dehydrogenation barrier on a (1 × 5) reconstructed surface is lower than that on (1 × 3) one, which demonstrate the experimental results that the formation temperature of a (1 × 3) reconstructed surface is higher than that of a (1 × 5) one.

Measuring subhalo mass in redMaPPer clusters with CFHT Stripe 82 Survey

We use the shear catalog from the CFHT Stripe-82 Survey to measure the subhalo masses of satellite galaxies in redMaPPer clusters. Assuming a Chabrier Initial Mass Function (IMF) and a truncated NFW model for the subhalo mass distribution, we find that the sub-halo mass to galaxy stellar mass ratio increases as a function of projected halo-centric radius $r_p$, from $M_{\rm sub}/M_{\rm star}=4.43^{+ 6.63}_{- 2.23}$ at $r_p \in [0.1,0.3]$ $h^{-1}Mpc$ to $M_{\rm sub}/M_{\rm star}=75.40^{+ 19.73}_{- 19.09}$ at $r_p \in [0.6,0.9]$ $h^{-1}Mpc$. We also investigate the dependence of subhalo masses on stellar mass by splitting satellite galaxies into two stellar mass bins: $10<\log(M_{\rm star}/M_{\rm sun})<10.5$ and $11<\log(M_{\rm star}/M_{\rm sun})<12$. The best-fit subhalo mass of the more massive satellite galaxy bin is larger than that of the less massive satellites: $\log(M_{\rm sub}/M_{\rm sun})=11.14 ^{+ 0.66 }_{- 0.73}$ ($M_{\rm sub}/M_{\rm star}=19.5^{+19.8}_{-17.9}$) versus $\log(M_{\rm sub}/M_{\rm sun})=12.38 ^{+ 0.16 }_{- 0.16}$ ($M_{\rm sub}/M_{\rm star}=21.1^{+7.4}_{-7.7}$).

Introduction to sheet-bulk metal forming

Sheet-bulk metal forming as a new class of manufacturing processes is one of the possible answers production processes provide to the increasing demands on functional integration into light weight parts made of high strength steel. Research in this field is carried out in several places. The special issue was initiated by the Transregional Collaborative Research Centre 73. It contains newest results from this research initiative as well as international results in the field of sheet-bulk metal forming.

Experimental and numerical analysis of tribological effective surfaces for forming tools in Sheet-Bulk Metal Forming

Sheet-Bulk Metal Forming (SBMF) allows the manufacture of complex parts with integrated functional form elements, such as teeth and thickened areas. Therefore, bulk forming operations are applied to sheets with initial thicknesses of 2 or 3 mm. The design and functionality of the tools are as important as the process itself. Therefore, the working group “Tools” of the Transregional Collaborative Research Centre on Sheet-Bulk Metal Forming (CRC/TR73) focuses on the optimization of the technical tool design. By varying topographies or applying tailored coatings, the friction behavior is changed to achieve a better form filling and to reduce process forces during the forming operations. In this paper, the potential of different tailored surfaces is validated by simulations and experimental studies. The tribological behavior of 14 surface microstructures is evaluated using a half-space model in order to select structures suitable for application. Those were characterized experimentally by ring-compression and pin-extrusion tests. The determined friction factors were used in a forming simulation to predict the form filling of small cavities in a flow forming operation. Furthermore, special attention is paid to the utilization of the anisotropic behavior of specific structures. The results were validated by an incremental gear forming process.

Companion-Technology for Cognitive Technical Systems

We introduce the Transregional Collaborative Research Centre “Companion-Technology for Cognitive Technical Systems”—a cross-disciplinary endeavor towards the development of an enabling technology for Companion-systems. These systems completely adjust their functionality and service to the individual user. They comply with his or her capabilities, preferences, requirements, and current needs and adapt to the individual’s emotional state and ambient conditions. Companion-like behavior of technical systems is achieved through the investigation and implementation of cognitive abilities and their well-orchestrated interplay.

Monitoring and Modeling the Terrestrial System from Pores to Catchments: The Transregional Collaborative Research Center on Patterns in the Soil–Vegetation–Atmosphere System

Abstract Most activities of humankind take place in the transition zone between four compartments of the terrestrial system: the unconfined aquifer, including the unsaturated zone; surface water; vegetation; and atmosphere. The mass, momentum, and heat energy fluxes between these compartments drive their mutual state evolution. Improved understanding of the processes that drive these fluxes is important for climate projections, weather prediction, flood forecasting, water and soil resources management, agriculture, and water quality control. The different transport mechanisms and flow rates within the compartments result in complex patterns on different temporal and spatial scales that make predictions of the terrestrial system challenging for scientists and policy makers. The Transregional Collaborative Research Centre 32 (TR32) was formed in 2007 to integrate monitoring with modeling and data assimilation in order to develop a holistic view of the terrestrial system. TR32 is a long-term research program funded by the German national science foundation Deutsche Forschungsgemeinschaft (DFG), in order to focus and integrate research activities of several universities on an emerging scientific topic of high societal relevance. Aiming to bridge the gap between microscale soil pores and catchment-scale atmospheric variables, TR32 unites research groups from the German universities of Aachen, Bonn, and Cologne, and from the environmental and geoscience departments of Forschungszentrum Jülich GmbH. Here, we report about recent achievements in monitoring and modeling of the terrestrial system, including the development of new observation techniques for the subsurface, the establishment of cross-scale, multicompartment modeling platforms from the pore to the catchment scale, and their use to investigate the propagation of patterns in the state and structure of the subsurface to the atmospheric boundary layer.

Genome sequence of the Wenxinia marina type strain (DSM 24838(T)), a representative of the Roseobacter group isolated from oilfield sediments.

Wenxinia marina Ying et al. 2007 is the type species of the genus Wenxinia, a representative of the Roseobacter group within the alphaproteobacterial family Rhodobacteraceae, isolated from oilfield sediments of the South China Sea. This family was shown to harbor the most abundant bacteria especially from coastal and polar waters, but was also found in microbial mats, sediments and attached to different kind of surfaces.Here we describe the features of W. marina strain HY34T together with the genome sequence and annotation of strain DSM 24838T and novel aspects of its phenotype. The 4,181,754 bp containing genome sequence encodes 4,047 protein-coding genes and 59 RNA genes. The genome of W. marina DSM 24838T was sequenced as part of the activities of the Genomic Encyclopedia of Type Strains, Phase I: the one thousand microbial genomes (KMG) project funded by the DoE and the Transregional Collaborative Research Centre 51 (TRR51) funded by the German Research Foundation (DFG).

Complete genome sequence of the bacteriochlorophyll a-containing Roseibacterium elongatum type strain (DSM 19469(T)), a representative of the Roseobacter group isolated from Australian coast sand.

Roseibacterium elongatum Suzuki et al. 2006 is a pink-pigmented and bacteriochlorophyll a-producing representative of the Roseobacter group within the alphaproteobacterial family Rhodobacteraceae. Representatives of the marine ‘Roseobacter group’ were found to be abundant in the ocean and play an important role in global and biogeochemical processes. In the present study we describe the features of R. elongatum strain OCh 323T together with its genome sequence and annotation. The 3,555,102 bp long genome consists of one circular chromosome with no extrachromosomal elements and is one of the smallest known Roseobacter genomes. It contains 3,540 protein-coding genes and 59 RNA genes. Genome analysis revealed the presence of a photosynthetic gene cluster, which putatively enables a photoheterotrophic lifestyle. Gene sequences associated with quorum sensing, motility, surface attachment, and thiosulfate and carbon monoxide oxidation could be detected. The genome was sequenced as part of the activities of the Transregional Collaborative Research Centre 51 (TRR51) funded by the German Research Foundation (DFG).