Artificial micro-swimmers in simulated natural environments

Microswimmers, such as bacteria, are known to show different behaviours depending on their local environment. They identify spatial chemical gradients to find nutrient rich areas (chemotaxis) and interact with shear flows to accumulate in high shear regions. Recently, artificial microswimmers have been developed which mimic their natural counterparts in many ways. One of the exciting topics in this field is to study these artificial motors in several natural settings like the ones bacteria interact with. In this Focus article, we summarize recent observations of artificial swimmers in chemical gradients, shear flows and other interesting natural environments simulated in the lab using microfluidics and nanotechnology.

Fabrication and applications of complex-shaped microparticles via microfluidics

Complex-shaped microparticles (MPs) have attracted extensive interest in a myriad of scientific and engineering fields in recent years for their distinct morphology and capability in combining different functions within a single particle. Microfluidic techniques offer an intriguing method for fabricating MPs with excellent monodispersity and complex morphology in parallel while controlling their number and size precisely and independently. To date, there are two notable microfluidics approaches for the synthesis of complex-shaped MPs, namely droplet based, and flow-lithography based microfluidics approaches. It is undoubted that the application of complex-shaped MPs via microfluidic fabrication will hold great promise in a variety of fields including microfabrication, analytical chemistry and biomedicine.

Spontaneous Ophthalmic Diseases in 586 New Zealand White Rabbits

The purpose of this study was to investigate spontaneous eye disease in New Zealand White (NZW) rabbits, which are commonly used for toxicity tests, and to provide reference materials for pharmaceutical companies and research centers. A total of 586 NZW rabbits were randomly chosen without sex preference and were examined using ocular equipment, including a direct ophthalmoscope, an indirect ophthalmoscope, a slit-lamp biomicroscope, a focal illuminator, and a fundus camera. This study showed that the incidence rate of temporary cataracts, regarded as a change within normal variation, was 0.5% in the NZW rabbits. Regarding abnormal ophthalmic disease, blepharitis was the most commonly observed ocular disease. Other findings included cataract, conjunctivitis, choroidal hypoplasia, keratitis, corneal scarring, eyelid laceration, posterior synechiae, uveitis, dacryocystitis, and persistent pupillary membrane. In total, the incidence rate of ophthalmic diseases was 9.6%. Based on sex and age distributions, females had more ocular diseases than males, and rabbits were less susceptible to eye diseases as they got older. In this study, photographs were taken to document findings, such as normal fundus, normal variations, ophthalmic disease, and histopathologic examination.