In a new study performed in humans, researchers from Karolinska Institutet have determined the age of atherosclerotic plaques by taking advantage of Carbon-14 (14C) residues in the atmosphere, prevailing after the extensive atomic bomb tests in the 50ties and 60ties. The findings, published in the scientific online journal PLoS ONE, suggest that in most people plaque formation occurs during a relatively short and late time period in life of 3-5 years.
The investigators collected carotid plaques during carotid stenosis surgery at the Stockholm South General Hospital (Södersjukhuset). The patients were admitted for surgery since their carotid lesions partly obstructed the blood flow to the brain, causing symptoms of insufficient oxygen called Trans Ischemic Attacks (TIA) that in some cases also had lead to strokes.
The plaques were carbon dated at Uppsala University, by using Accelerator Mass Spectrometry (AMS). As a result of the extensive atomic bomb test in the 50-ties and 60-ties, the atmospheric concentration of 14C rapidly increased. Since then the concentration of 14C is declining, which now can be used to determine the time of synthesis of any biological sample.
Beauty is said to be in the eye of the beholder, but a new study reveals that the reverse is also true; unattractiveness is in the eye of the beheld. Research published in Ethology finds that people with bloodshot eyes are considered sadder, unhealthier and less attractive than people whose eye whites are untinted, a cue which is uniquely human.
“Red, ‘bloodshot’ eyes are prominent in medical diagnoses and in folk culture”, said lead author Dr. Robert R. Provine from the University of Maryland, Baltimore County. “We wanted to know if they influence the everyday behaviour and attitudes of those who view them, and if they trigger perceptions of attractiveness.”
Bloodshot eyes occur when the small blood vessels of the usually transparent conjunctiva membrane on the surface of the eye become enlarged and congested with blood, giving a red tint to the underlying sclera, the “white” of the eyes. Redness of the sclera is believed to be a general but important sign of a person’s emotional and biological state.