Brandenburg University of Technology Cottbus-Senftenberg

The interface between biomaterials and biological systems is crucial for medical implants and tissue engineering. Surface modifications are a key strategy for controlling interactions. Synthetic glycopolymers offer a versatile toolbox, mimicking the structure and function of natural glycoconjugates like mucins. This review highlights the significance of glycopolymers for targeted surface modifications of established biomaterials, such as silicones and poly(meth)acrylates. Controlled polymerization techniques, like the reversible-addition-fragmentation chain-transfer (RAFT) polymerization, enable the synthesis of well-defined glycopolymer architectures. Glycopolymeric surface functionalization creates tailored interfaces for different biological responses, from preventing protein and cell adhesion to promoting specific cell-type binding. The focus lies on using single, well-characterized polymeric base materials and tuning their surface properties through glycopolymer coatings to achieve various and specific functions. This approach opens new dimensions in the development of advanced biomaterials for applications like contact lenses, drug delivery systems, and biosensors and also possesses potential regulatory advantages by leveraging the safety profiles of existing materials.

Die Replik macht sich dafür stark, dass Inklusion in der Erwachsenenbildung nicht nur den Aspekt der Teilhabe, sondern auch den aktiven Beitrag der Teilgabe berücksichtigen sollte, der im englischen Begriff ‚participation‘ bereits stärker inbegriffen ist. Damit wird die Forderung dialogischer Reflexivität in der Erwachsenenbildung ernst genommen. Fokussiert wird eine machtkritische, vulnerabilitätssensible Perspektive, die weniger problematisiert, sondern Bedingungen des Gelingens betont. So rückt das Anliegen einer offenen, selbstreflexiven Haltung in den Vordergrund.

There is growing evidence that oxidative stress contributes not only to the pathophysiology of atherosclerosis but also to acute kidney injury (AKI). This study investigated the prognostic value of nHDLox (normalized high-density lipoprotein with reduced antioxidant function) in hospitalized patients with AKI. nHDLox was measured within 48 hours of AKI diagnosis. We assessed its performance in predicting the following primary endpoints: in-hospital all-cause mortality, need for kidney replacement therapy (KRT), and restoration of kidney function before discharge. Secondary endpoints included clinical markers of severe disease course: intensive care treatment, ventilatory support, and vasopressor requirement. Among 132 participants, 16.7% died in the hospital, 36.4% required KRT, and 31.1% had no restoration of kidney function. For all primary endpoints, nHDLox levels were significantly higher in non-survivors (2.00 vs. 1.26; +58.7%; p = 0.009), in patients requiring KRT (1.66 vs. 1.23; +34.9%; p = 0.002), and in those without renal recovery (1.71 vs. 1.23; +39.0%; p = 0.001). nHDLox was independently associated with death, KRT, and lack of renal recovery, with odds ratios for a twofold increase (95% CI) of 1.88 (1.19-2.98), 1.78 (1.17-2.69), and 2.09 (1.34-3.26), respectively. Predictive performance was moderate, with AUC-ROC values (95% CI) of 0.68 (0.54-0.81), 0.66 (0.56-0.76), and 0.67 (0.57-0.78). No differences were observed across secondary endpoints. Impaired antioxidant HDL function is closely associated with clinically relevant AKI outcomes. nHDLox, therefore, represents a significant risk factor in both cardiovascular and kidney disease.

One-dimensional turbulence (ODT) offers an alternative single-column solver for wall-bounded turbulence that sits between traditional 1D boundary-layer parametrisations and fully 3D direct numerical simulation: in fully resolved mode, molecular transport is explicitly resolved along a 1D vertical domain, while turbulent advection is represented by instantaneous spatial mappings ("eddy events"). For high-Reynolds-number, wall-bounded flows relevant to the atmospheric boundary layer (ABL), resolving Kolmogorov scales is prohibitively expensive. This motivates careful implementation of wall models and subgrid scale models in ODT similar to large eddy simulations (LES).Here, we develop an ODT formulation operated in an LES-like mode, in which unresolved eddy events are represented by a Smagorinsky–Lilly subgrid-scale (SGS) model, and surface coupling is provided through standard surface parametrisations for an extended range of resolved scales. We assess the formulation on two benchmark problems: (i) canonical smooth turbulent channel flow, using an algebraic wall model to supply surface stress consistent with resolved inertial-sublayer dynamics; and (ii) the GABLS1 intercomparison case (a weakly stable, shear-driven ABL with prescribed surface cooling rate), using Monin-Obukhov similarity theory to compute surface momentum and heat fluxes.Together, these two cases demonstrate the feasibility of combining ODT's eddy-event transport with LES-style SGS and surface models, thus providing a computationally efficient platform for future studies of ABL regimes, in which turbulence, surface fluxes, entrainment across sharp inversions, and multi-phase physics interact and remain challenging for coarse-resolution weather and climate models.

This study presents, for the first time, a comprehensive multi-fidelity aero-thermo-fluid framework (spanning 0D-analytical, 1D and 3D domains) applied to the analysis of a structural oil-to-air Fan Outlet Guide Vane Cooler (FOGVC) in a jet engine. Addressing the need for efficient thermal management in next-generation engines, a hierarchical approach is established to characterize both thermal dissipation and pressure drop performance. The framework compares five simulation levels—ranging from high-fidelity conjugate heat transfer to 0D analytical models—across two distinct internal geometries (a rectangular inverted-U and a circular coil) covering different flow regimes. The research quantifies the trade-offs between physical fidelity and computational cost, establishing a decision-making criterion for the design of complex structural coolers. Results demonstrate that while 0D analytical methods provide high accuracy-to-speed ratios for temperature prediction, they exhibit significant deviations in pressure drop estimation and lack of capture local thermal gradients critical to structural integrity, where high-fidelity fully coupled 3D simulations are indispensable.Furthermore, the analysis reveals fundamental limitations in current passive heat exchanger designs under extreme operating conditions, suggesting a paradigm shift toward active or adaptive components is required to meet future dissipation targets.

Abstract In this study, the influence of various process parameters on the porosity of Ti-6Al-4V parts fabricated via Powder Bed Fusion – Laser Based (PBF-LB) is investigated. Three different layer thicknesses (30 μm, 60 μm, and 120 μm) were analyzed to define process windows enabling a build-rate acceleration while keeping the porosity below 0.1%. Through iterative parameter refinement, the effects of laser power, scan speed and hatch distance were examined in terms of linear energy density (LED), energy transmission density (ETD) and volumetric energy density (VED), and their influence on the formation of process-related defects such as pores. Correlations between these energy metrics and pore formation types (keyhole vs. lack-of-fusion) are discussed. The results demonstrate that process acceleration by a factor of more than 3 is possible while maintaining high quality of the components in terms of internal porosity. In addition, an accelerated method for manufacturing components using the PBF-LB process is presented, in which components are manufactured at very high build-rates but with increased porosity and then brought to the target porosity of 0.1% using the HIP process. This has made it possible to accelerate the build-rate in PBF-LB production by a further 32%. Accounting for the additional time required for HIP, the HIP route is faster than using the accelerated, which achieves the target porosity in as-built condition, for parts larger than 1421 cm 3 .

Abstract. Tropical dry forests play an important role in the global carbon cycle, but their responses to climate variability are still not well understood. Using a three-year period (April 2022 to March 2025) of eddy covariance measurements, we studied seasonal and annual controls on carbon balances in a Tumbesian dry forest in Southern Ecuador. During the study period, the forest functioned as a net carbon sink, with a net ecosystem exchange (NEE) of -285 gCm−2 year−1. The strongest carbon uptake occurred during the wet period (Feb–May) with 173.86 ± 66 gCm−2 month−1, while it was reduced to 39.80 ± 8.12 gCm−2 month−1 in the dry season (August–November). Light use efficiency (LUE) and water use efficiency (WUE) were used to characterize the functional controls on carbon fluxes at both seasonal and annual scales. WUE showed relatively stable water–carbon exchange, whereas LUE displayed clear seasonal variation, reflecting the strong influence of seasonal vegetation growth and greenness. Principle component analysis (PCA) was conducted to further analyze controlling mechanisms in carbon fluxes. Seasonal results showed that gross primary productivity (GPP) was mainly controlled by energy-related factors, while ecosystem respiration (Reco) was primarily driven by a moisture–temperature gradient. Annually, GPP was predominantly influenced by variations in vapor pressure deficit (VPD), soil temperature (Ts), and incoming radiation (Rg), reflecting a strong coupling between surface energy balance and atmospheric moisture demand. These drivers were further modulated by ENSO related climate variability, as reflected by shifts in their PCA loadings across years. Overall, the results reveal a decoupling between photosynthesis and respiration and show that tropical dry forests are highly vulnerable to increasing climate extremes, highlighting the need for improved representation of these processes in Earth system models.

ABSTRACT The pressure to reduce greenhouse gas emissions is growing, which demands new and innovative technologies to produce mobile as well as stationary energy. The methanation offers a pathway to reduce greenhouse gas emissions by directly converting to . This also plays a crucial role in “power‐to‐gas” (P2G) technologies by providing an approach to store excess renewable energy in the form of methane in an existing natural gas infrastructure. However, methanation is a complex process due to its exothermic nature, interaction of the gas species with the catalyst, and possible catalyst degradation. Therefore, a deeper understanding is required for the methanation reaction, its different reaction pathways, and side reactions. In this work, we aim to understand the direct production of synthetic natural gas from and in a Sabatier process with the help of experiments over a Ni/ catalyst. A detailed surface reaction mechanism is developed to extend the study numerically by validating the simulation results with the experimental data. A one‐dimensional model, LOGEcat, based on a single‐channel catalyst model, is used for kinetic modeling. Experiments as well as simulations have been performed at various conditions, such as temperature variation and dilution to the inlet composition. We have successfully captured the experimental trends using the kinetic model developed for the conditions considered for the analysis.