Open Access

We have shown that in murine cardiomyopathy caused by overexpression of the β1-adrenoceptor, Gαi2-deficiency is detrimental. Given the growing evidence for isoform-specific Gαi-functions, we now examined the consequences of Gαi3 deficiency in the same heart-failure model. Mice overexpressing cardiac β1-adrenoceptors with (β1-tg) or without Gαi3-expression (β1-tg/Gαi3−/−) were compared to C57BL/6 wildtypes and global Gαi3-knockouts (Gαi3−/−). The life span of β1-tg mice was significantly shortened but improved when Gαi3 was lacking (95% CI: 592–655 vs. 644–747 days). At 300 days of age, left-ventricular function and survival rate were similar in all groups. At 550 days of age, β1-tg but not β1-tg/Gαi3−/− mice displayed impaired ejection fraction (35 ± 18% vs. 52 ± 16%) compared to wildtype (59 ± 4%) and Gαi3−/− mice (60 ± 5%). Diastolic dysfunction of β1-tg mice was prevented by Gαi3 deficiency, too. The increase of ANP mRNA levels and ventricular fibrosis observed in β1-tg hearts was significantly attenuated in β1-tg/Gαi3−/− mice. Transcript levels of phospholamban, ryanodine receptor 2, and cardiac troponin I were similar in all groups. However, Western blots and phospho-proteomic analyses showed that in β1-tg, but not β1-tg/Gαi3−/− ventricles, phospholamban protein was reduced while its phosphorylation increased. Here, we show that in mice overexpressing the cardiac β1-adrenoceptor, Gαi3 deficiency slows or even prevents cardiomyopathy and increases shortened life span. Previously, we found Gαi2 deficiency to aggravate cardiac dysfunction and mortality in the same heart-failure model. Our findings indicate isoform-specific interventions into Gi-dependent signaling to be promising cardio-protective strategies.

This research aims at evaluating the use of drone (UAV) imagery in the monitoring of hydromorphological changes in a segment of Erft River in Neuss-Gnadental, which has undergone restoration. In four flight campaigns from February 2022 to November 2023, UAV images were processed with open-source photogrammetry and point clouds processing software (WebODM and CloudCompare) to create 2D orthophotos and 3D point clouds. These products supported delineation of the channel and calculation of geometric properties such as the length, sinuosity, and number of meanders which indicated good correspondence with restoration design objectives and continuous morphological changes like erosion, sediment bars, and woody debris. Hydromorphological quality at the segment scale was assessed by employing an adapted LAWA protocol using only the 2D orthomosaics and 3D point clouds. Analysis showed that restoration of the river segment produced improvements in characteristics such as flow variety, substrate type, and banks while the near “technical” parts of the segment experienced small alterations. The UAV flights were conducted frequently, enabling documentation of seasonal fluctuations that might not have been observed if the surveys had been carried out using satellite imagery. Certain advantages included centimetre-resolution imagery, flexibility in flight schedules, and visuals friendly to stakeholder impact. Nevertheless, there were specific workflow challenges. Utilising photogrammetry on open-source tools had high computational costs and required hands-on troubleshooting. Vegetation overshadows complicated semi-automated classification routines and requires manual refinement for reliable channel delineation. However, the approach proved effective for high-resolution, local-to-reach-scale monitoring, strengthening adaptive, data-driven management of river restoration sites. Subsequent campaigns should include data from multiple sensors (LiDAR, multispectral), the inclusion of classification algorithms, and longer, repeated surveys to evaluate the hydromorphological characteristics under different flow conditions. In summary, UAV imagery enhances hydromorphological monitoring and provides a powerful yet still-developing tool for science-based evaluation of restoration efforts.

With the increasing threats of climate change and the associated rise in climate extremes and natural hazards, there has been a growing focus on studies addressing mitigation and adaptation strategies for these hazards, one of which is urban heat islands (UHI). The strategies for mitigating UHI are well-established, with urban green infrastructure being one of the most effective approaches. Previous research has shown that green infrastructure can significantly reduce urban temperatures, although its effectiveness varies depending on specific properties. The cooling effectiveness of these infrastructures differs based on various factors.This paper investigates the cooling potential of various types of green infrastructure, including trees, green roofs, and vertical greenery, in a 16-ha area in Cologne's Volksgarten quarter, based on their biophysical properties. The primary objective was to develop a criteria set for green infrastructure characteristics that enhance cooling potential and climate resilience and to apply this set in assessing the area’s cooling potential. A mixed-methods approach was employed, incorporating literature analysis to define the criteria sets, alongside spatial analysis, in-situ observations, and transpiration modelling to evaluate the study area’s actual cooling potential. The results indicated that, particularly for trees, shading properties based on ecological characteristics such as LAI, height, and crown width play a significant role. For green roofs and vertical greenery, system type characteristics and orientation are potentially more influential. The analysis also included the number of existing infrastructures and based on evaluations of these groups and their locations within the study area, it was possible to identify so-called “cool” and “hot spots” in the study area. The study concludes that while current green infrastructure implementations in the study area have medium cooling potential, there are also clear opportunities for improvement. From these findings, a targeted set of recommendations was drafted to not only enhance cooling potential and climate resistance but also to incorporate additional co-benefits, where specifically for trees, it was possible to make such recommendations even on the species level. This study offers a novel approach to evaluating mitigation strategies, contributing to a deeper understanding of the role of green infrastructure in urban climate resilience, and providing an approach to optimising its benefits with potential implications for urban planners.

The aldol reaction of bio acetone in presence of a strongly basic ion exchange resin was carried out with and without the addition of water in a temperature range between − 30 °C and 45 °C. The conversion, selectivity and service time of the ion exchange resins were investigated in a stirred batch reactor and a continuous fixed bed reactor. For the batch experiments, both conversion and selectivity increased with decreasing temperature. Furthermore, the addition of water to the reaction medium has a positive effect on selectivity and catalyst service time of the resins. For the continuous flow experiments carried out in a fixed bed reactor, the selectivity towards diacetone alcohol is higher than in a batch reactor. This high selectivity is favored by a short contact time which inhibits as expected most of the consecutive reactions.

Hydroperoxide lyases (HPLs) catalyze the splitting of 13S-hydroperoxyoctadecadienoic acid (13S-HPODE) into the green note flavor hexanal and 12-oxo-9(Z)-dodecenoic acid, which is not yet used industrially. Here, HPL from Carica papaya (HPLCP) was cloned and functionally expressed in Escherichia coli to investigate synthesis of 12-oxo-9(Z)-dodecenoic acid in detail. To improve the low catalytic activity of full-length HPLCP, the hydrophobic, non-conserved N-terminal sequence was deleted. This enhanced enzyme activity from initial 10 to 40 U/l. With optimization of solubilization buffer, expression media enzyme activity was increased to 2700 U/l. The tetrameric enzyme was produced in a 1.5 l fermenter and enriched by affinity chromatography. The enzyme preparation possesses a slightly acidic pH optimum and a catalytic efficiency (kcat/KM) of 2.73 × 106 s−1·M−1 towards 13S-HPODE. Interestingly, HPLCP-N could be applied for the synthesis of 12-oxo-9(Z)-dodecenoic acid, and 1 mM of 13S-HPODE was transformed in just 10 s with a yield of 90%. At protein concentrations of 10 mg/ml, the slow formation of the 10(E)-isomer traumatin was observed, pointing to a non-enzymatic isomerization process. Bearing this in mind, a one-pot enzyme cascade starting from safflower oil was developed with consecutive addition of Pseudomonas fluorescens lipase, Glycine max lipoxygenase (LOX-1), and HPLCP-N. A yield of 43% was obtained upon fast extraction of the reaction mixtures after 1 min of HPLCP-N reaction. This work provides first insights into an enzyme cascade synthesis of 12-oxo-9(Z)-dodecenoic acid, which may serve as a bifunctional precursor for bio-based polymer synthesis.