Automated electrochemical oxygen sensing using a 3D-printed microfluidic lab-on-a-chip system.

Dissolved oxygen is crucial for metabolism, growth, and other complex physiological and pathological processes; however, standard physiological models (such as organ-on-chip systems) often use ambient oxygen levels, which do not reflect the lower levels that are typically found . Additionally, the local generation of reactive oxygen species (ROS; a key factor in physiological systems) is often overlooked in biology-mimicking models. Here, we present a microfluidic system that integrates electrochemical dissolved oxygen sensors with lab-on-a-chip technology to monitor the physiological oxygen concentrations and generate hydrogen peroxide (HO; a specific ROS).

Control of liquid crystals combining surface acoustic waves, nematic flows, and microfluidic confinement.

The optical properties of liquid crystals serve as the basis for display, diagnostic, and sensing technologies. Such properties are generally controlled by relying on electric fields. In this work, we investigate the effects of microfluidic flows and acoustic fields on the molecular orientation and the corresponding optical response of nematic liquid crystals.

Spontaneous shock waves in pulse-stimulated flocks of Quincke rollers.

Active matter demonstrates complex spatiotemporal self-organization not accessible at equilibrium and the emergence of collective behavior. Fluids comprised of microscopic Quincke rollers represent a popular realization of synthetic active matter. Temporal activity modulations, realized by modulated external electric fields, represent an effective tool to expand the variety of accessible dynamic states in active ensembles.

[Strangulated postoperative diaphragmatic hernia].

We present a rare case of postoperative diaphragmatic hernia in a patient with colon infringement 3 years after surgery for cardioesophageal cancer accompanied by extensive diaphragmotomy. The diagnosis of diaphragmatic hernia with colon infringement was based on a combination of anamnestic, clinical and radiological data, as well as results of diagnostic pleural puncture. This clinical case is of interest due to small incidence of disease and difficult interpretation of clinical and diagnostic data.

Motility of acoustically powered micro-swimmers in a liquid crystalline environment.

Suspensions of microswimmers in liquid crystals demonstrate remarkably complex dynamics and serve as a model system for studying active nematics. So far, experimental realization of microswimmers suspended in liquid crystalline media has relied on biological microorganisms that impose strict limitations on the compatible media and makes it difficult to regulate activity. Here, we demonstrate that acoustically powered bubble microswimmers can efficiently self-propel in a lyotropic liquid crystal.