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Glioblastoma, the most frequent primary malignant brain tumour in adults, is characterised by profound yet dynamic hypoxia and nutrient depletion. To sustain survival and proliferation, tumour cells are compelled to acquire metabolic plasticity with the induction of adaptive metabolic programs. Here, we interrogated the pathways necessary to enable processing of nutrients other than glucose. We employed genetic approaches (stable/inducible overexpression, CRISPR/Cas9 knockout), pharmacological interventions with a novel inhibitor of AMP‐activated protein kinase (AMPK) in glioblastoma cell culture systems and a proteomic approach to investigate mechanisms of metabolic plasticity. Moreover, a spatially resolved multiomic analysis was employed to correlate the gene expression pattern of PGC‐1α with the local metabolic and genetic architecture in human glioblastoma tissue sections. A switch from glucose to alternative nutrients triggered an activation of AMPK, which in turn activated PGC‐1α‐dependent adaptive programs promoting mitochondrial metabolism. This sensor‐effector mechanism was essential for metabolic plasticity with both functional AMPK and PGC‐1α necessary for survival and growth of cells under nonglucose nutrient sources. In human glioblastoma tissue specimens, PGC‐1α‐expression correlated with nonhypoxic tumour niches defining a specific metabolic compartment. Our findings reveal a cell‐intrinsic nutrient sensing and switching mechanism. The exposure to alternative fuels triggers a starvation signal that subsequently is passed on via AMPK and PGC‐1α to induce adaptive programs necessary for broader spectrum nutrient metabolism. The integration of spatially resolved transcriptomic data confirms the relevance of PGC‐1α especially in nonhypoxic tumour regions. Thus, the AMPK‐PGC‐1α axis is a candidate for therapeutic inhibition in glioblastoma. Key Points/Highlights: AMPK activation induces PGC‐1α expression in glioblastoma during nutrient scarcity.PGC‐1α enables metabolic plasticity by facilitating metabolism of alternative nutrients in glioblastoma.PGC‐1α expression is inversely correlated with hypoxic tumour regions in human glioblastomas. [ABSTRACT FROM AUTHOR]

This paper aims at providing an overview of the ways for residue valorization in the iron and steelmaking industry. The important role of recycling in iron and steelmaking as a cornerstone for achieving a cleaner and resource-efficient potential is described. Several research results concerning metals and metal oxides (scrap, scale), slags, dusts, process gases, and water recycling from the iron and steelmaking process are reviewed here, aiming to detect those research gaps that still need implementation and suggest potential approaches toward potential solutions. Through a comprehensive evaluation, several possibilities are provided to incorporate effectively in metallurgical processes the bio-based or bio-derived carbon materials, namely biomass, biochar, biocoke, and polymers from waste plastics to reduce the dependence on fuel and reducing agents from fossil sources, and therefore mitigating the related environmental impact of the steel industry. Eventually, this review highlights the importance of embracing circular economy (CE) principles in iron and steelmaking, along with considering opportunities for industrial symbiosis (IS) and exploring the role of digitalization and digital solutions in recycling practices. [ABSTRACT FROM AUTHOR]

This paper studies the integration of direct reduced iron (DRI) and hot briquetted iron (HBI) into the steelmaking process via an electric arc furnace (EAF). Considering a variety of DRI production techniques distinguished by different reactor types, this paper provides a comparative overview of the current state. It delves into significant challenges, such as the susceptibility of DRI to reoxidation and the necessity of thorough handling to maintain its quality. The effectiveness of several reoxidation mitigation strategies, including the application of thin oxide layers, briquetting, various coatings, and nitride formation in ammonia-based reduction processes, is evaluated. Most existing studies have primarily focused on the reoxidation of DRI rather than on HBI, despite the fact that HBI may undergo reoxidation. The importance of DRI/HBI in offering an alternative to the integrated steelmaking route is highlighted, focusing on how it changes the EAF process compared to those for melting scrap. This paper also identifies several research prospects for further DRI/HBI applications in steel production. [ABSTRACT FROM AUTHOR]

The RecoDust process is a pyrometallurgical process for treating steel mill dusts that cannot be recycled internally due to their zinc content, providing numerous benefits compared to conventional processes. State-of-the-art processes often face the problem of recycling only zinc, but not iron, which is frequently landfilled and withdrawn from a closed loop. Furthermore, these processes are also often limited to a specific zinc content in the feedstock. Within the described RecoDust smelting campaigns, basic oxygen converter dust with about 15 wt.% zinc was taken as feedstock. After high-temperature treatment of the input material, the RecoDust slag (RDS) has a zinc content of 0.4 wt.% and the crude zinc oxide (CZO) has a ZnO content of up to 80 wt.%. The RDS is suitable for use in the sinter plant as a secondary raw material. To investigate the influence of adding RDS to a common sintering mixture, sintering pot tests followed by RDI (reduction disintegration indices) tests were carried out. The influence of the admixture of RDS on the RDI values is not detectable. The CZO was fed into a soda extraction system for halogen removal. The halogen removal of this two-stage leaching was highly efficient with over 90% for chlorine. [ABSTRACT FROM AUTHOR]

Fluxes are added to steelmaking process to form basic slag and limit refractory lining consumption. Early formation of CaO- and MgO-saturated slag is critical for process productivity. To achieve this, flux must be dissolved in the melt in a limited process time, and the properties of a slag additive influence the fluxing efficiency. The dissolution behavior of samples with different qualities (i.e. raw dolomite, limestone, soft-burnt and hard-burnt quicklime and dolime) was investigated in the pre-melted model BOF and EAF slags at 1673 K and 1723 K. The disc-shaped sample was immersed into the melt and left there until slag solidification was reached. After a holding time between 5 and 20 minutes, the crucible with the sample were quenched with liquid nitrogen. The fused samples were analyzed by SEM method. Based on comparison of slag morphology and concentration changes in the slag, the dissolution behavior of the samples was examined. [ABSTRACT FROM AUTHOR]

The addition of basic additives in steelmaking processes is essential because these lead to slag adaptation and enable refining reactions. In calcination treatment, the process parameters temperature and dwell time influence the decomposition of dolomite as a magnesium‐containing lime substitute. It results in specific properties such as varying residual fractions of carbonates CaCO3·MgCO3 and porosity. The properties affect the dissolution kinetics, and the fast and complete dissolution is of interest. Hence, the static high‐temperature dissolution tests using dolomite‐based samples in diverse conditions (raw, modified, soft‐burnt, and hard‐burnt) are executed to determine the impact of the calcination state. The specimens are immersed in synthetic electric arc furnace slag, including 10 wt% Al2O3, 25 wt% SiO2, 25 wt% CaO, 8 wt% MnO, and 32 wt% FeO. The dolomite or dolime dissolves in the stagnant oxidic melt within the reaction time of 10 min at 1450 °C. The resulting chemistries of quenched slags, representing the current dissolution status, are examined by scanning electron microscopy using energy‐dispersive X‐ray spectroscopy analysis on metallographically prepared cross‐sections and via X‐ray fluorescence analysis of mechanically extracted slag fractions. The dissolution performance is characterized and compared for the different additive materials. [ABSTRACT FROM AUTHOR]