Exploring Structural Nuances in Germanium Halide Perovskites using Solid-state 73Ge and 133Cs NMR Spectroscopy

Metal-halide perovskites remain top candidates for better-performing photovoltaic devices but concerns with leading lead-based materials continue. Ge perovskites remain understudied for use in solar cells compared to their Sn-based counterparts. In this work, we undertake a combined 133Cs and 73Ge solid-state NMR and DFT study of the bulk CsGeX3 (X = Cl, Br, I) series. We show how seemingly small structural variations within germanium halide perovskites have major consequences on their 73Ge and 133Cs NMR signatures and reveal a near cubic-like phase at room temperature for CsGeCl3 with severe local Ge polyhedral distortion. Quantum chemical computations are effective at predicting the structural impact on NMR parameters for 73Ge and 133Cs. This study demonstrates the value of a combined experimental and theoretical approach for investigating attractive materials for energy applications – providing information that is out of reach with conventional characterization methods – and adds the challenging 73Ge nucleus to the toolkit.

Sequence and structure comparison of ATP synthase F0 subunits 6 and 8 in notothenioid fish

Mitochondrial changes such as tight coupling of the mitochondria have facilitated sustained oxygen and respiratory activity in haemoglobin-less icefish of the Channichthyidae family. We aimed to characterise features in the sequence and structure of the proteins directly involved in proton transport, which have potential physiological implications. ATP synthase subunit a (ATP6) and subunit 8 (ATP8) are proteins that function as part of the F0 component (proton pump) of the F0F1complex. Both proteins are encoded by the mitochondrial genome and involved in oxidative phosphorylation. To explore mitochondrial sequence variation for ATP6 and ATP8 we analysed sequences from C. gunnari and C. rastrospinosus and compared them with their closely related red-blooded species and eight other vertebrate species. Our comparison of the amino acid sequence of these proteins reveals important differences that could underlie aspects of the unique physiology of the icefish. In this study we find that changes in the sequence of subunit a of the icefish C. gunnari at position 35 where there is a hydrophobic alanine which is not seen in the other notothenioids we analysed. An amino acid change of this type is significant since it may have a structural impact. The biology of the haemoglobin-less icefish is necessarily unique and any insights about these animals will help to generate a better overall understanding of important physiological pathways.

Compositional and Verbal Aspect in Greek: The Aorist Imperfect Distinction and the Article-Aspect Interplay

According to an aspectological model proposed by Kabakčiev in 1984, later developed and sophisticated, languages differ according to whether they mark aspect (perfectivity and imperfectivity) on verbs, as in the Slavic languages – among others, or through nouns/NPs featuring (non-)boundedness which is transferred onto verbs, as in the Germanic languages – among others. In this model of compositional aspect (CA), Bulgarian is a borderline case with a perfective-imperfective and an aorist-imperfect distinction and a definite article only (no indefinite), and the model is used to analyze Greek, a language exhibiting identical features. NP referents play a major role for the compositional explication of aspect. The study finds that Greek is of the same borderline/hybrid type of language as Bulgarian, featuring verbal aspect (VA) predominantly, but also peripherally CA. The aorist/imperfect distinction exists both in Greek and Bulgarian to offset the structural impact of the definite article. Analyzed are some conditions for the explication of CA in Greek and they are found similar to those in Bulgarian. However, there are specificites and differences between the two languages that must be further studied and identified. Keywords: verbal aspect, compositional aspect, definite article, article-aspect interplay, aorist-imperfect contrast

Structural Impact on Some Common Physical Properties of Single Jersey Weft Knit Fabric

Single jersey weft knit fabrics include a large portion of knitted products. These fabrics are made using different types of stitches. In this study, several single jersey weft knit fabric samples containing four courses and two wales in the repeating unit of the fabric structure were made by introducing and gradually increasing the number of tuck stitches in the structure, to find out the effect of this stitch on fabric properties. Results showed that tuck stitches could positively affect the areal density, width, and tensile properties of the fabric. For some comfort-related properties, tuck stitches were found to improve wicking and drying properties, reduce water vapor transmission rate, and affect fabric smoothness. The position of tuck stitches in the structure also had some effect, but was not as significant as when the number of tuck stitches was varied.

Identity Ambivalence among the Eurasian Macanese: Historical Dynamics, Political Regimes and Eating Practices

This article focuses on the case study of an ethnically and culturally mixed Eurasian Macanese community through their phenomenological experience of identity ambivalence. Our thematic framework includes the structural impact of colonial and postcolonial political regimes in Macao, historical influences on contemporary identity and sociocultural expressions of creolisation. It is argued that the Macanese people illustrate the memory of the ambivalent encounter between the two extremities of the Eurasia (China and Portugal) which started in the 16th-c. and never ceased moving forces to the present day. Furthermore, in the context of fieldwork with the Macanese community in Portugal, an ethnographic approach helps reveal the ambivalent dynamics of similarities and differentiation with respect to food practices and commensality as expressed over dinner by a group of close friends in Lisbon.