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Covalent bonding interactions determine the energy–momentum (E–k) dispersion (band structure) of solid-state materials. Here, we show that noncovalent interactions can modulate theE–kdispersion near the Fermi level of a low-dimensional nanoscale conductor. We demonstrate that low energy band gaps may be opened in metallic carbon nanotubes through polymer wrapping of the nanotube surface at fixed helical periodicity. Electronic spectral, chiro-optic, potentiometric, electronic device, and work function data corroborate that the magnitude of band gap opening depends on the nature of the polymer electronic structure. Polymer dewrapping reverses the conducting-to-semiconducting phase transition, restoring the native metallic carbon nanotube electronic structure. These results address a long-standing challenge to develop carbon nanotube electronic structures that are not realized through disruption of π conjugation, and establish a roadmap for designing and tuning specialized semiconductors that feature band gaps on the order of a few hundred meV. 

This article analyzes the use of several response particles in face-to-face interaction in Wa’ikhana, an East Tukano language of northwestern Amazonia. Adopting a Conversation Analysis approach, we explore details of each particle, considering their prosodic shapes, the action contexts in which they occur, and their sequential positioning, all crucial to understanding their meanings in interaction. Our analysis shows that Wa’ikhana response particles exhibit both universal and language-particular properties, thus demonstrating the contributions of data from lesser-studied languages to research on language in social interaction, and the value of an interactional approach in the study of under-described, and often endangered, indigenous languages. 

In the wake of widespread and ongoing travel restrictions that began in early 2020 due to the COVID-19 pandemic, many documentary linguists worldwide shifted to remote work methods in order to continue or, in some cases, begin new projects. This pandemic situation has prompted questions about both methodological and ethical considerations in doing remote fieldwork. In this paper, we discuss the pros and cons of working remotely and discuss ways of working remotely based on our experiences working on projects in West Africa, northwest Amazonia, and Indonesia. We argue that elements of remote fieldwork should become a permanent part of linguistic fieldwork, but that such methods need to be considered in the context of decolonizing language documentation and centering the community’s needs and interests.