Permeability-selectivity trade-off for a universal leaky channel inspired by mobula filters.

Mobula rays have evolved leaf-shaped filter structures to separate food particles from seawater, which function similarly to industrial cross-flow filters. Unlike cross-flow filtration, where permeability and selectivity are rationally designed following trade-off analyses, the driving forces underlying the evolution of mobula filter geometry have remained elusive. To bridge the principles of cross-flow and mobula filtration, we establish a universal framework for the permeability-selectivity trade-off in a leaky channel inspired by mobula filters, where permeability and selectivity are characterized by the pore-scale leaking rate and the cut-off particle size, respectively.

Crack densification in drying colloidal suspensions.

As sessile drops of aqueous colloidal suspensions dry, a close-packed particle deposit forms that grows from the edge of the drop toward the center. To compensate for evaporation over the solid's surface, water flows radially through the deposit, generating a negative pore pressure in the deposit associated with tensile drying stresses that induce the formation of cracks. As these stresses increase during drying, existing cracks propagate and additional cracks form, until the crack density eventually saturates.

Fracture and relaxation in dense cornstarch suspensions.

Dense suspensions exhibit the remarkable ability to switch dynamically and reversibly from a fluid-like to a solid-like, shear-jammed (SJ) state. Here, we show how this transition has important implications for the propensity for forming fractures. We inject air into bulk dense cornstarch suspensions and visualize the air invasion into the opaque material using time-resolved X-ray radiography.

Setting new priorities for nursing research: The updated Swiss Nursing Research Agenda-a systematic, participative approach.

Aim: To identify current key areas for nursing research in Switzerland, we revised the Swiss Research Agenda for Nursing (SRAN) initially published in 2008.

Background: By developing a research agenda, nursing researchers internationally prioritize and cluster relevant topics within the research community. The process should be collaborative and systematic to provide credible information for decisionmakers in health care research, policy, and practice.