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Diverse chemical, energy, environmental, and industrial processes involve the flow of polymer solutions in porous media. The accumulation and dissipation of elastic stresses as the polymers are transported through the tortuous, confined pore space can lead to the development of an elastic flow instability above a threshold flow rate, producing a transition from steady to unsteady flow characterized by strong spatiotemporal fluctuations, despite the low Reynolds number (Re≪1). Furthermore, in 1D ordered arrays of pore constrictions, this unsteady flow can undergo a second transition to multistability, where distinct pores simultaneously exhibit distinct unsteady flow states. Here, we examine how this transition to multistability is influenced by fluid rheology. Through experiments using diverse polymer solutions having systematic variations in fluid shear-thinning or elasticity, in pore constriction arrays of varying geometries, we show that the onset of multistability can be described using a single dimensionless parameter, given sufficient fluid elasticity. This parameter, the streamwise Deborah number, compares the stress relaxation time of the polymer solution to the time required for the fluid to be advected between pore constrictions. Our work thus helps to deepen understanding of the influence of fluid rheology on elastic instabilities, helping to establish guidelines for the rational design of polymeric fluids with desirable flow behaviors. 

In this paper we describe semantic fieldwork undertaken from a distance with speakers of Akuzipik (also known as (Siberian) Yupik), an endangered Alaska Native language. We present our experiences in working both synchronously and asynchronously on temporal reference, quantification, lexical semantics of derivational morphology, and antipassives with speakers via Facebook Messenger, text message, email, mail, and telephone. We detail a number of logistical, methodological, and interpersonal challenges and benefits to conducting semantic fieldwork via these means both during the global pandemic and before/after. While fieldworkers have found the situation more challenging than in-person fieldwork in many ways, scheduling time with speakers is easier, and some speakers favor the extra time afforded them to think about their answers. Relationships among fieldworkers and speakers have benefitted from more extended interactions than are possible during in-person trips, and fieldworkers have been able to engage with speakers who had been unavailable during in-person visits. 

Akuzipik (Yupigestun/Yupik/St. Lawrence Island Yupik/Siberian Yupik/Chaplinski Yupik) is an endangered language belonging to the Yupik branch of the Inuit-Yupik-Unangan language family. It is currently spoken by 800-900 people in the Bering Strait region, mainly on St. Lawrence Island, Alaska (St. Lawrence Island Yupik), and on the coast of the Chukotka Peninsula, in Russia (Chaplinski Yupik) (de Reuse 1994; Schwartz et al. 2019). The linguistic differences between these two varieties seem to be minor and not affect mutual intelligibility (Krauss 1975). The language has been undergoing a rapid generational shift, beginning in the 1950s in Russia and in the 1990s in Alaska (Schwartz et al. 2019). 

Akuzipik (Yupigestun/Yupik/St. Lawrence Island Yupik/Siberian Yupik/Chaplinski Yupik) is an endangered language belonging to the Yupik branch of the Inuit-Yupik-Unangan language family. It is currently spoken by 800-900 people in the Bering Strait region, mainly on St. Lawrence Island, Alaska (St. Lawrence Island Yupik), and on the coast of the Chukotka Peninsula, in Russia (Chaplinski Yupik) (de Reuse 1994; Schwartz et al. 2019). The linguistic differences between these two varieties seem to be minor and not affect mutual intelligibility (Krauss 1975). The language has been undergoing a rapid generational shift, beginning in the 1950s in Russia and in the 1990s in Alaska (Schwartz et al. 2019). 

St. Lawrence Island Yupik (ISO 639-3: ess) is an endangered polysynthetic language in the Inuit-Yupik language family indigenous to Alaska and Chukotka. This work presents a step-by-step pipeline for the digitization of written texts, and the first publicly available digital corpus for St. Lawrence Island Yupik, created using that pipeline. This corpus has great potential for future linguistic inquiry and research in NLP. It was also developed for use in Yupik language education and revitalization, with a primary goal of enabling easy access to Yupik texts by educators and by members of the Yupik community. A secondary goal is to support development of language technology such as spell-checkers, text-completion systems, interactive e-books, and language learning apps for use by the Yupik community.