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Abstract Necessary diversification of battery chemistry and related cell design call for investigation of more exotic materials and configurations, such as solid-state potassium batteries. In the core of their development lies the necessity of discovering new and electrochemically more efficient inorganic solid-state electrolytes. This review focuses on suitable chemical structures, their fundamental properties and status of the materials synthesis, related electrochemical performance, contemporary characterization techniques and modeling efforts for inorganic solid-state potassium electrolytes.

The practical phases of teacher education programs are of high relevance for pre-service teachers and their professional development. The challenges posed by the COVID-19 pandemic and the resulting changes in schools might have affected pre-service teachers' learning experiences during the long-term internships of initial teacher education programs in various ways. This article focuses on pre-service teachers' experiences during their practical term during the COVID-19 pandemic. We will address three questions: first, how did pre-service teachers experience different kinds of learning activities in school (e.g., the delivery of and reflection on teaching); second, how did they perceive social support and their learning success associated with the implementation of learning activities in different areas of teaching; and third, which types of learning activities and social support were predictive of their perception of learning success? To this end, we will present findings from a cross-sectional survey which was conducted in the academic year 2020/21. A total of 164 pre-service teachers from different universities in North Rhine-Westphalia, Germany, participated in the online survey after having completed their practical term. The results of the study illustrate heterogeneous experiences concerning the preparation and implementation of remote teaching scenarios during the internship. Despite changes in schools due to the pandemic, pre-service teachers perceived a high level of social support and learning success during their practical term. Own teaching experiences and social support from mentors have proved to be relevant predictors for the perception of learning success.

The influence of relaxation and rejuvenation on the deformation behavior of the Zr-based bulk metallic glass Vit105 (Zr52.5Cu17.9Ni14.6Al10Ti5) was investigated, where a well-defined thermal history was systematically introduced by thermal treatments. Samples with a progressively lower fictive temperature exhibit a lower enthalpic state, coupled with a reduced degree of free volume, which is responsible for a continuous embrittlement observed in three-point beam bending tests. The generated database allows an assessment of the mechanical behavior of any amorphous component made of Vit105 by simple calorimetric measurements and the determination of the fictive temperature, which is of special interest for complex parts that cannot be easily evaluated in mechanical tests. Diffraction experiments with high energy synchrotron X-ray radiation reveal a correlation between the increase in rigid 3-atom cluster connections with the reduction in the fracture strain, as a measure of ductility, indicating a strong correlation with the thermal history. While the atomic connections seem to have a crucial contribution to the ductility, changes of the short- and medium-range order seem to be equally important. The current findings provide fundamental insights into the role of thermal history in metallic glass forming alloy systems and how it can be used to manipulate the structure and tailor their mechanical properties specifically to the needs of each application.

Abstract Numerous genetic and epidemiologic studies have demonstrated an association between elevated levels of lipoprotein(a) (Lp[a]) and cardiovascular disease. As a result, lowering Lp(a) levels is widely recognized as a promising strategy for reducing the risk of new-onset coronary heart disease, stroke, and heart failure. Lp(a) consists of a low-density lipoprotein-like particle with covalently linked apolipoprotein A (apo[a]) and apolipoprotein B-100, which explains its pro-thrombotic, pro-inflammatory, and pro-atherogenic properties. Lp(a) serum concentrations are genetically determined by the apo(a) isoform, with shorter isoforms having a higher rate of particle synthesis. To date, there are no approved pharmacological therapies that effectively reduce Lp(a) levels. Promising treatment approaches targeting apo(a) expression include RNA-based drugs such as pelacarsen, olpasiran, SLN360, and lepodisiran, which are currently in clinical trials. In this comprehensive review, we provide a detailed overview of RNA-based therapeutic approaches and discuss the recent advances and challenges of RNA therapeutics specifically designed to reduce Lp(a) levels and thus the risk of cardiovascular disease.

Abstract DNA polymerase III sliding clamp (DnaN) was recently validated as a new anti-tuberculosis target employing griselimycins. Three (2 S,4 R)−4-methylproline moieties of methylgriselimycin play significant roles in target binding and metabolic stability. Here, we identify the mycoplanecin biosynthetic gene cluster by genome mining using bait genes from the 4-methylproline pathway. We isolate and structurally elucidate four mycoplanecins comprising scarce homo-amino acids and 4-alkylprolines. Evaluating mycoplanecin E against Mycobacterium tuberculosis surprisingly reveals an excitingly low minimum inhibition concentration at 83 ng/mL, thus outcompeting griselimycin by approximately 24-fold. We show that mycoplanecins bind DnaN with nanomolar affinity and provide a co-crystal structure of mycoplanecin A-bound DnaN. Additionally, we reconstitute the biosyntheses of the unusual l-homoleucine, l-homonorleucine, and (2 S,4 R)−4-ethylproline building blocks by characterizing in vitro the full set of eight enzymes involved. The biosynthetic study, bioactivity evaluation, and drug target validation of mycoplanecins pave the way for their further development to tackle multidrug-resistant mycobacterial infections.

New titanium-based metallic glasses containing sulphur as a key element have recently been developed and are the subject of ongoing research related to the effects of sulphur introduction into glass-forming alloy systems. Here we report on the formation of sulphuric precipitates during solidification of a Ti40Zr35Cu17S8 alloy and on the occurrence of secondary intermetallic compound crystallization starting in sulphur-depleted zones around the precipitates. The alloy is a promising metallic glass for use as a structural and biomedical material as it shows a high yield strength and good corrosion resistance paired with a low density. The role of sulphur for the glass formation in the Ti-Zr-Cu-S system is discussed and specimens quenched into different structural states are investigated by means of high-energy synchrotron diffraction and electron microscopy. The electron microscopic findings reveal that sulphuric precipitates precede the crystallization of an intermetallic (Ti, Zr)2Cu phase, which is the primary phase when sulphur is not present in the system and thus lead to a higher glass-forming ability. The sulphuric precipitates are found in specimens of various casting thickness and differ in their volume percentages depending on the size of the cast sample, while the secondary phase (Ti, Zr)2Cu crystallizes heterogeneously in the interfaces between the sulphuric precipitates and the local matrix.

We investigated the change in the structure and dynamics of a Ni–Nb bulk metallic glass upon sulfur addition on both microscopic and macroscopic scales. With the sulfur concentration of 3 at. %, where the composition Ni58Nb39S3 exhibits the best glass forming ability in the investigated sulfur concentration range, both the equilibrium and undercooled melt dynamics remain almost unchanged. Only in the glassy state does sulfur seem to result in mass transport less decoupled to the viscosity of the undercooled liquid, where the measured Ag tracer diffusion coefficient is slower in the ternary alloy. With the structural disorder introduced by the alloying sulfur, the improved glass forming ability is attributed to geometrical frustration, where crystal nucleation requires a depletion of sulfur and hence long range diffusion, as long as no primary sulfur-containing crystalline phase is involved.

Die Sportpädagogik und die Sportdidaktik haben sich mit einem gewissen zeitlichen Verzug gegenüber den Didaktiken der naturwissenschaftlichen Fächer und der Mathematik den Anforderungen einer „neuen“ Aufgabenkultur zugewendet. Die Lernaufgabe wird als ergänzendes Aufgabenformat zur Bewegungsaufgabe diskutiert. Zur konzeptionellen Ausdifferenzierung in eine sportorientierte, eine künstlerisch-pädagogische und eine bewegungspädagogische Auslegung der Bewegungsaufgabe finden sich eine Reihe empirischer Studien zur aufgabenorientierten Gestaltung des Sportunterrichts. Jüngst wird die Aufgabenanalysefähigkeit von Sportlehrkräften in den Blick genommen. Zielebenen der entfalteten Aktivitäten sind die Entwicklung guter Aufgaben und die Qualifizierung von Sportlehrkräften für die Erteilung guten Sportunterrichts.

A comparative analysis of the attachment efficacy of sharpened vs blunted air terminals under a strong background DC electric field, similar to conditions found in naturally occurring lightning events, is presented. Testing was conducted using an oil-free, 17-stage, 1.4 MV bipolar Marx generator with a biased discharge plane that emulated the conditions found prior to the lightning return stroke. The biased discharge plane allowed the introduction of a strong DC electric field and subsequent corona formation on a time scale much longer than the brief duration over which the downward leader propagates. Initial observations indicate that despite a higher background electric field at the sharpened terminals, leading to pre-discharge corona formation where none is seen on the blunt terminal, both the sharpened and blunted terminals exhibit similar attachment probabilities during discharge events, with some discharge events attaching to both terminals.

„Raum erkunden / Exploring Space“. Editorial

Abstract Background Chimeric antigen receptor (CAR) T-cells are a promising approach in cancer immunotherapy, particularly for treating hematologic malignancies. Yet, their effectiveness is limited when tackling solid tumors, where immune cell infiltration and immunosuppressive tumor microenvironments (TME) are major hurdles. Fibroblast activation protein (FAP) is highly expressed on cancer-associated fibroblasts (CAFs) and various tumor cells, playing an important role in tumor growth and immunosuppression. Aiming to modulate the TME with increased clinical safety and effectiveness, we developed novel small and size-extended immunotheranostic UniCAR target modules (TMs) targeting FAP. Methods The specific binding and functionality of the αFAP-scFv TM and the size-extended αFAP-IgG4 TM were assessed using 2D and 3D in vitro models as well as in vivo. Their specific tumor accumulation and diagnostic potential were evaluated using PET studies after functionalization with a chelator and suitable radionuclide. Results The αFAP-scFv and -IgG4 TMs effectively and specifically redirected UniCAR T-cells using 2D, 3D, and in vivo models. Moreover, a remarkably high and specific accumulation of radiolabeled FAP-targeting TMs at the tumor site of xenograft mouse models was observed. Conclusions These findings demonstrate that the novel αFAP TMs are promising immunotheranostic tools to foster cancer imaging and treatment, paving the way for a more convenient, individualized, and safer treatment of cancer patients. Graphical Abstract