Publications by authors named "D I Gwynne"

Needle-based injections currently enable the administration of a wide range of biomacromolecule therapies across the body, including the gastrointestinal tract, through recent developments in ingestible robotic devices. However, needles generally require training, sharps management and disposal, and pose challenges for autonomous ingestible systems. Here, inspired by the jetting systems of cephalopods, we have developed and evaluated microjet delivery systems that can deliver jets in axial and radial directions into tissue, making them suitable for tubular and globular segments of the gastrointestinal tract.

View Article and Find Full Text PDF

The prevalence and diversity of female ornaments pose a challenge to evolutionary theory because males should prefer mates that spend resources on offspring rather than on ornaments. Among dance flies, there is extraordinary variation in sexual dimorphism. Females of many species have conspicuous ornaments (leg scales and inflatable abdominal sacs).

View Article and Find Full Text PDF

The rapid increase in aquaculture over the last several decades has led to concerns about the environmental impact of fish feeds relying on marine resources for fishmeal (FM). We aim to assess Nannochloropsis sp. QH25 co-product as a viable and sustainable replacement for FM in juvenile rainbow trout, Oncorhynchus mykiss, feeds.

View Article and Find Full Text PDF
Article Synopsis
  • The gut-brain axis connects the gastrointestinal system with the brain and influences various physiological functions, including feeding and emotions, and can be manipulated using pharmaceuticals or surgeries, which often come with risks.
  • Traditional electrical stimulation of the GI tract requires invasive procedures for electrode placement, while stimulating mucosal tissue has been difficult due to the presence of digestive fluids.
  • The newly developed FLASH capsule is an ingestible device inspired by the "thorny devil" lizard, designed to actively wick fluid and stimulate mucosal tissue to modulate gut hormones safely, with potential applications in treating metabolic, gastrointestinal, and neuropsychiatric disorders without invasive methods.
View Article and Find Full Text PDF

Male parental investment is expected to be associated with high confidence of paternity. Studies of species with exclusive male parental care have provided support for this hypothesis because mating typically co-occurs with each oviposition, allowing control over paternity and the allocation of care. However, in systems where males invest by feeding mates (typically arthropods), mating (and thus the investment) is separated from egg-laying, resulting in less control over insemination, as male ejaculates compete with rival sperm stored by females, and a greater risk of investing in unrelated offspring (cuckoldry).

View Article and Find Full Text PDF