Publications by authors named "A P Petroff"

Copper is an essential trace metal for biological processes in humans and animals. A low level of copper detection at physiological pH using fluorescent probes is very important for in vitro applications, such as the detection of copper in water or urine, and in vivo applications, such as tracking the dynamic copper concentrations inside cells. Copper homeostasis is disrupted in neurological diseases like Alzheimer's disease, and copper forms aggregates with amyloid beta (Ab42) peptide, resulting in senile plaques in Alzheimer's brains.

View Article and Find Full Text PDF

Thiovulum majus, which is one of the fastest known bacteria, swims using hundreds of flagella. Unlike typical pusher cells, which swim in circular paths over hard surfaces, T. majus localize near hard boundaries by turning their flagella to exert a net force normal to the surface.

View Article and Find Full Text PDF

Simple and reproducible 3D cell culture systems that mimic biological interactions within physiological tissues (biomimetics) can provide unique insight for scientific inquiries compared to 2D cell cultures. Fibroblast-populated collagen lattices (FPCLs) are commonly used for mimicking physiological collagen matrices, potentiating biomechanical stresses on embedded fibroblasts. Here, we describe a novel 3D co-culture model that incorporates human Tenon's capsule fibroblasts embedded in FPCLs co-cultured with THP-1 monocytes suspended in culture media.

View Article and Find Full Text PDF

Our planet is a self-sustaining ecosystem powered by light energy from the sun, but roughly closed to matter. Many ecosystems on Earth are also approximately closed to matter and recycle nutrients by self-organizing stable nutrient cycles, e.g.

View Article and Find Full Text PDF

We demonstrate that edge currents develop in active chiral matter due to boundary shielding over a wide range of densities corresponding to a gas, fluid, and crystal. The system is composed of spinning disk-shaped grains with chirally arranged tilted legs confined in a circular vibrating chamber. The edge currents are shown to increasingly drive circulating bulk flows with area fraction as percolating clusters develop due to increasing spin-coupling between neighbors mediated by frictional contacts.

View Article and Find Full Text PDF