A stunning image of a mouse embryo halfway through pregnancy is one of two photos submitted by Oxford University researchers to be shortlisted for a national competition.

The British Heart Foundation's annual Reflections of Research competition challenges researchers to showcase awe-inspiring displays of life-saving research.

'Blooming development', submitted by Dr Victoria Rashbrook, shows a mouse embryo at the point where the early heart is forming, resembling a tulip in bloom.

Dr Rashbrook said: "I am delighted to be shortlisted for the British Heart Foundation’s Reflections of Research competition and share this awe-inspiring image of developing life.

"We hope this image can highlight the remarkable beauty of science and nature."

Dr Rashbrook and her team are using powerful microscopes to study how infant health and pregnancy are linked, aiming to better understand the cause of life-limiting heart defects and find new ways to treat and prevent them.

The second shortlisted image taken by an Oxford researcher, 'Igniting a new ‘wave’ of AF research', was submitted by Aaron Johnston.

'Igniting a new ‘wave’ of AF research', submitted by Aaron Johnston'Igniting a new ‘wave’ of AF research', submitted by Aaron Johnston (Image: Aaron Johnston, University of Oxford, British Heart Foundation - Reflections of Research) It shows the structure of a cell from the heart of a patient with atrial fibrillation (AF), a major cause of stroke.

Mr Johnston said: "Our image highlights how the cells, the key players in scarring of the heart in AF, change their shape, structure, and activity as the condition progresses.

"In our ongoing work, we hope to better understand how AF develops, and, most importantly, develop better treatments for this debilitating condition.”