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Jumping droplets are interesting because of their applications in energy harvesting, heat transfer, anti-icing surfaces, and displays. Typically, droplets “jump” from a surface when two or more drops coalesce. Here, we demonstrate an approach to get a single droplet of liquid metal (eutectic gallium indium) to jump by using electrochemistry in a solution of 1M NaOH. Applying a positive potential to the metal (∼1 V relative to the open circuit potential) drives electrochemical surface oxidation that lowers the interfacial tension from ∼450 mN/m to ∼0 mN/m. In the low interfacial tension state, the droplet flattens due to gravity. Rapid switching to a negative potential (relative to the open circuit potential) reduces the surface oxide, returning the deformed droplet to a state of high interfacial tension. This rapid change in interfacial tension in the flattened state generates excess surface energy, which drives the droplet to return to a spherical shape with enough momentum that the liquid droplet jumps. This work is unique because (1) the jumping is controlled and tuned electrically, (2) the approach works with a single droplet, (3) it does not require a superhydrophobic surface, which is typically used to prevent droplets from adhering to the substrate, (4) the drops jump through a viscous medium rather than air, and (5) the potential energy obtained by the jumping drops is one order of magnitude higher than previous approaches. Yet, a limitation of this approach relative to conventional jumping drops is the need for electrolyte and a source of electricity to enable jumping. Herein, we characterize and optimize the jumping height (∼6 mm for a 3.6 mm diameter drop) by changing the reductive and oxidative potential and time.

Helminthic therapy has shown considerable promise as a means of alleviating some inflammatory diseases that have proven resistant to pharmaceutical intervention. However, research in the field has been limited by a lack of availability to clinician scientists of a helminth that is relatively benign, non-communicable, affordable, and effectively treats disease. Previous socio-medical studies have found that some individuals self-treating with helminths to alleviate various diseases are using the rat tapeworm (cysticercoid developmental stage of Hymenolepis diminuta; HDC). In this study, we describe the production and use of HDCs in a manner that is based on reports from individuals self-treating with helminths, individuals producing helminths for self-treatment, and physicians monitoring patients that are self-treating. The helminth may fit the criteria needed by clinical scientists for clinical trials, and the methodology is apparently feasible for any medical center to reproduce. It is hoped that future clinical trials using this organism may shed light on the potential for helminthic therapy to alleviate inflammatory diseases. Further, it is hoped that studies with HDCs may provide a stepping stone toward population-wide restoration of the biota of the human body, potentially reversing the inflammatory consequences of biota depletion that currently affect Western society.