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Practical reproducibility is the ability to reproduce results is a manner that is cost-effective enough to become a vehicle of mainstream scientific exploration. Since computational research artifacts usually require some form of computing to interpret, open and programmable infrastructure, such as a range of NSF-supported testbeds spanning infrastructure from datacen- ter through networks to wireless systems, is a necessary – but not sufficient – requirement for reproducibility. The question arises what other services and tools should build on the availability of such programmable infrastructure to foster the development and sharing of findable, accessible, integrated, and reusable (FAIR) experiments that underpin practical reproducibility. In this paper, we propose three such services addressing the problems of packaging for reuse, findability, and accessibility, respectively. We describe how we developed these services in Chameleon, an NSF-funded testbed for computer science research which has supported the research of a community of 8,000+ users, and discuss their strengths and limitations. 

Recently, a large family of at least 14 discotic liquid crystals was discovered that are exceptions to the conventional paradigm that discotic mesogens tend to feature long, flexible tails on their periphery. To understand why these materials are liquid crystals, as well as the structural determinants of discotic phase behavior, we studied a group of closely related small tail-free disk-like molecules, including both mesogenic and non-mesogenic compounds differing only in the position of a single fluorine substituent. The rigidity and structural simplicity of these molecules make them well suited to for study by large, fully all-atom simulations. Using a combination of static and dynamic metrics, we were able to identify several key features of the columnar mesophase and, thereby, conclusively identify a columnar liquid crystalline mesophase present in a subset of our systems. Our simulations feature molecules hopping between columns in the columnar mesophase and distinctive molecular rotations in 60° steps about the columnar axis. The ability to create and characterize columnar mesophases in silico provides a potent tool for untangling the structural determinants of liquid crystalline behavior in these and other tail-free discotic liquid crystals.