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We show that Clifford algebras provide a natural language to describe the physics of liquid crystal defects in 3D. This framework shows that most of these defects have fermionic nature, as the director field profile on a 2D cross section can algebraically be represented by a spinor. Defects in uniaxial, biaxial nematics, and cholesterics are represented by elements belonging to different Clifford algebras, suggesting that there are fundamental distinctions between topological defects in each of these phases. Our theory allows nematic defects to be interpreted as Majorana-like spinors, as defects and antidefects are topologically equivalent, while some cholesteric defects, such as screw dislocations, are better viewed as Weyl-like spinors of well-defined chirality. Defects can be described by a “defect bivector,” an algebraic element that quantifies the rototranslation associated with them. In cholesterics, fermionic defects of different types can combine to yield composite quasiparticles with either fermionic or bosonic nature. Under cylindrical confinement, these quasiparticles provide the way to understand the structure of screw dislocations. In the bulk, they may condensate to form topological phases, such as blue phases or skyrmion lattices. Our results provide a surprising link between liquid crystals, particle physics, and topological quantum matter. 

Phenological response to global climate change can impact ecosystem functions. There are various data sources from which spatiotemporal and taxonomic phenological data may be obtained: mobilized herbaria, community science initiatives, observatory networks, and remote sensing. However, analyses conducted to date have generally relied on single sources of these data. Siloed treatment of data in analyses may be due to the lack of harmonization across different data sources that offer partially nonoverlapping information and are often complementary. Such treatment precludes a deeper understanding of phenological responses at varying macroecological scales. Here, we describe a detailed vision for the harmonization of phenological data, including the direct integration of disparate sources of phenological data using a common schema. Specifically, we highlight existing methods for data harmonization that can be applied to phenological data: data design patterns, metadata standards, and ontologies. We describe how harmonized data from multiple sources can be integrated into analyses using existing methods and discuss the use of automated extraction techniques. Data harmonization is not a new concept in ecology, but the harmonization of phenological data is overdue.We aim to highlight the need for better data harmonization, providing a roadmap for how harmonized phenological data may fill gaps while simultaneously being integrated into analyses. 

While online community research is prevalent in CSCW, there are limited ethical principles for conducting research that may affect online communities. At the same time, a growing body of evidence suggests that traditional ethical review focused on research with individuals fails to fully capture the complexities of online community research. To support advancing ethical online community research, we propose a one-day hybrid workshop centered around tensions and challenges in adopting best practices for ethical online community research. This workshop aims to bring together online community researchers to 1) recognize existing approaches for ethical online community research, 2) expose gaps in current practices, and 3) prioritize directions to reconcile these ethical challenges. 

Attempting the hands-on activities typical of makerspaces without in-person expert facilitation can lead to frustration and decreased engagement. This study aims to explore the collaboration affordances of REACH, a novel communication device that allows users to share gestures around a common artifact while in separate locations. Using a modified version of the divergent collaborative learning mechanisms framework (DCLM), this paper highlights the affordances of REACH to support students in collaboratively engaging in joint attention and boundary spanning perception and action, even when they are physically disparate.