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Knowledge about capacity losses related to the solid electrolyte interphase (SEI) in sodium‐ion batteries (SIBs) is still limited. One major challenge in SIBs is that the solubility of SEI species in liquid electrolytes is comparatively higher than the corresponding species formed in Li‐ion batteries. This study sheds new light on the associated capacity losses due to initial SEI formation, SEI dissolution and subsequent SEI reformation, charge leakage via SEI and subsequent SEI growth, and diffusion‐controlled sodium trapping in electrode particles. By using a variety of electrochemical cycling protocols, synchrotron‐based X‐ray photoelectron spectroscopy (XPS), gas chromatography coupled with mass spectrometry (GC‐MS), and proton nuclear magnetic resonance (1H‐NMR) spectroscopy, capacity losses due to changes in the SEI layer during different open circuit pause times are investigated in nine different electrolyte solutions. It is shown that the amount of capacity lost depends on the interplay between the electrolyte chemistry and the thickness and stability of the SEI layer. The highest capacity loss is measured in NaPF6 in ethylene carboante mixed with diethylene carbonate electrolyte (i.e., 5 µAh h−1/2pause or 2.78 mAh g·h−1/2pause) while the lowest value is found in NaTFSI in ethylene carbonate mixed with dimethoxyethance electrolyte (i.e., 1.3 µAh h−1/2pause or 0.72 mAh g·h−1/2pause). A detailed quantification of different aging mechanisms related to electrolyte solution and negative electrode is presented in this study. The dissolution of solid electrolyte interphase (SEI), diffusion‐controlled ion trapping, continuous SEI dissolution and reformation, and chemical desodiation and SEI growth in sodium‐ion batteries are discussed here using a variety of analytical tools.

Prussian blue analogues (PBAs), A x M [ M ′ ( CN ) 6 ] 1 - y · z H 2 O , are a highly functional class of materials with use in a broad range of applications, such as energy storage, due to their porous structure and tunable composition. The porosity is particularly important for the properties and is deeply coupled to the cation, water, and [ M ′ ( CN ) 6 ] n - vacancy content. Determining internal porosity is especially challenging because the three compositional parameters are dependent on each other. In this work, we apply a new method, positron annihilation lifetime spectroscopy (PALS), which can be employed for the characterization of defects and structural changes in crystalline materials. Four samples were prepared to evaluate the method’s ability to detect changes in internal porosity as a function of the cation, water, and [ M ′ ( CN ) 6 ] n - vacancy content. Three of the samples have identical [ M ′ ( CN ) 6 ] n - vacancy content and gradually decreasing sodium and water content, while one sample has no sodium and 25% [ M ′ ( CN ) 6 ] n - vacancies. The samples were thoroughly characterized using inductively coupled plasma-optical emission spectroscopy (ICP-OES), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Mössbauer spectroscopy as well as applying the PALS method. Mössbauer spectroscopy, XRD, and TGA analysis revealed the sample compositions Na 1.8 ( 2 ) Fe 0.64 ( 6 ) 2 + Fe 0.36 ( 10 ) 2.6 + [ Fe 2 + ( CN ) 6 ] · 2.09 ( 2 ) H 2 O , Na 1.1 ( 2 ) Fe 0.24 ( 6 ) 2 + Fe 0.76 ( 6 ) 2.8 + [ Fe 2.3 + ( CN ) 6 ] · 1.57 ( 1 ) H 2 O , Fe [ Fe ( CN ) 6 ] · 0.807(9) H 2 O , and Fe [ Fe ( CN ) 6 ] 0.75 · 1.5 H 2 O , confirming the absence of vacancies in the three main samples. It was shown that the final composition of PBAs could only be unambiguously confirmed through the combination of ICP, XRD, TGA, and Mössbauer spectroscopy. Two positron lifetimes of 205 and 405 ps were observed with the 205 ps lifetime being independent of the sodium, water, and/or [ Fe ( CN ) 6 ] n - vacancy content, while the lifetime around 405 ps changes with varying sodium and water content. However, the origin and nature of the 405 ps lifetime yet remains unclear. The method shows promise for characterizing changes in the internal porosity in PBAs as a function of the composition and further development work needs to be carried out to ensure the applicability to PBAs generally. Graphical abstract

Extended duration of normothermic machine perfusion (NMP) provides opportunities to resuscitate suboptimal donor livers. This intervention requires adequate oxygen delivery typically provided by a blood-based perfusion solution. Methaemoglobin (MetHb) results from the oxidation of iron within haemoglobin and represents a serious problem in perfusions lasting > 24 h. We explored the effects of anti-oxidant, N -acetylcysteine (NAC) on the accumulation of methaemoglobin. NMP was performed on nine human donor livers declined for transplantation: three were perfused without NAC (no-NAC group), and six organs perfused with an initial NAC bolus, followed by continuous infusion (NAC group), with hourly methaemoglobin perfusate measurements. In-vitro experiments examined the impact of NAC (3 mg) on red cells (30 ml) in the absence of liver tissue. The no-NAC group sustained perfusions for an average of 96 (range 87–102) h, universally developing methaemoglobinaemia (≥ 2%) observed after an average of 45 h, with subsequent steep rise. The NAC group was perfused for an average of 148 (range 90–184) h. Only 2 livers developed methaemoglobinaemia (peak MetHb of 6%), with an average onset of 116.5 h. Addition of NAC efficiently limits formation and accumulation of methaemoglobin during NMP, and allows the significant extension of perfusion duration.

Autonomous driving and traffic flow simulation requires a realistic and accurate representation of the environment. Therefore, this research focuses on the semantic segmentation of aerial images for simulation purposes. Initially, a dataset was created based on true orthophotos from 2019 and Kempten’s street cadaster, with true orthophotos being fully rectified aerial images. The chosen classes were oriented towards the subsequent conversion and usage in simulation. The proposed labeling workflow used cadaster data and demonstrated significant time efficiency compared to state-of-the-art datasets. Subsequently, a neural network was implemented that was trained and tested on the dataset. In addition, the network was also trained only on the lane markings to compare the network’s performance. Both cases demonstrated excellent segmentation results. The generalizability was then tested on true orthophotos from 2021. The results indicated a solid generalizability, but still needs to be improved. Finally, the aerial information was converted into a 3D environment, that can be used in simulations. Our results confirm the usage of aerial imagery and street cadaster data as a basis for the simulations.

Background Normothermic machine perfusion of donor livers has become standard practice in the field of transplantation, allowing the assessment of organs and safe extension of preservation times. Alongside its clinical uses, there has been expanding interest in extended normothermic machine perfusion (eNMP) of livers as a potential vehicle for medical research. Reproducible extended normothermic machine perfusion has remained elusive due to its increased complexity and monitoring requirements. We set out to develop a reproducible protocol for the extended normothermic machine perfusion of whole human livers. Methods Human livers declined for transplantation were perfused using a blood-based perfusate at 36 °C using the Liver Assist device (XVIVO, Sweden), with continuous veno-venous haemofiltration in-parallel. We developed the protocol in a stepwise fashion. Results Perfusion techniques utilised included: targeted physiological vascular flows, phosphate replacement (to prevent hypophosphataemia), N-acetylcysteine (to prevent methaemoglobin accumulation), and the utilisation of sodium lactate as both a nutritional source and real-time measure of hepatocyte function. All five human livers perfused with the developed protocol showed preserved function with a median perfusion time of 168 h (range 120–184 h), with preserved viability throughout. Conclusions Livers can be reproducibly perfused in excess of 120 (range 121–184) hours with evidence of preserved hepatocyte and cholangiocyte function. Clarke et al. present a reproducible protocol for the extended normothermic machine perfusion of human livers. Function and are preserved in five human livers perfused between 121–184 h. Plain Language Summary Circulating blood through human livers at normal body temperature allows transplant surgeons to assess the function of the liver and safely extend the time it is out of the body prior to transplantation. Extending this perfusion of livers beyond 24 h has proven difficult. We evaluated improved techniques to circulate blood through the liver. We found the improved techniques could enable a machine to be used to reliably perfuse livers for more than 24 h, whilst preserving the function of the liver. Our improved method included varying the blood flow according to liver size and removing waste products from the circulating blood. Using our method could enable more livers to be used successfully in transplant operations, reducing the waiting times for people requiring liver transplantation and improving their quality of life.

Lake Tzibaná is one of the largest (1.27 km2) and deepest (Zmax = 52 m) karstic lakes in the UNESCO’s Biosphere Reserve “Nahá-Metzabok” and in the Lacandon Forest, southeastern Mexico. It archives sediments from multiple sources and the inflowing Nahá River forms deltaic deposits. In 2019, the water level in Lake Tzibaná declined by ~ 15 m, persisting for 4 months and exposing the Nahá River Delta. A geophysical profile on the exposed delta revealed an accumulation of ~ 20 m of such deposits. Three sediment outcrops from an inactive channel in the Nahá River Delta, which ranged in height from 0.6 to 1.43 m, were sampled and a multi-proxy analysis of biological remains and geochemical variables was conducted. Four facies were observed: (1) massive-coarse sand, (2) fine sand, (3) dark leaf litter and (4) massive silty clay, each characterized by specific microcrustacean, testate amoebae and diatom taxa. Six dark leaf litter horizons were radiocarbon dated and revealed a complex depositional history including inverted ages making the establishment of an age model difficult. Nevertheless, past lake-level changes and the formation of the four facies match three characteristic water-level stages, which can also be observed on recent satellite images: (1) Massive-coarse sand deposits, with compositional and sedimentological characteristics of a shoreline environment and fluvial lateral banks, were formed during large-magnitude reductions in the lake level, similar to the one in 2019, (2) Interbedded layers of fine sand and dark leaf litter, currently found in low-energy fluvial environments, were formed during shorter and less pronounced decrease intervals, and (3) Massive silty clay, with distinctive microorganisms from low-energy lacustrine environments, is deposited during high water-level stages, when the delta is covered by water. Our findings illustrate how hydrological changes alter sedimentary dynamics in deltaic areas of lakes. Despite the complexity of their depositional processes, deltaic records can serve as a complementary source of paleolimnological information to records from distal zones due to their sensitivity to variations in water level, especially during extreme and prolonged desiccation events. Future research should attempt to combine evidences from deltaic and sediment sequences from deeper zones of Lake Tzibaná to reconstruct water-level variations during the entire Holocene. Understanding past lake-level reductions is not only relevant for the local indigenous communities but also crucial for the conservation of this ecosystem of international importance.