According to a new study, sunlight continues to damage people’s skin and increase the risk of cancer for hours after exposure.
Scientists at Yale University discovered it was the supposedly protective pigment melanin that was causing the damage.
The research team says the findings may lead to better sunscreens that can prevent the extra damage.
When UV radiation pummels our skin cells, it can cause mutations in the DNA.
Melanin, the pigment behind a tan or natural skin tone, is the body’s defense as it absorbs the radiation.
What scientists did not know previously was what happens to all the energy that the melanin has absorbed.
The Yale team showed, in the journal Science, that the high-energy version of melanin supercharges a series of chemical reactions.
A cocktail of superoxides and peroxynitrites culminate in a “very high-energy molecule breaking apart and releasing the energy that was holding it together”, said lead researcher Prof. Douglas Brash.
In laboratory tests, the whole damage in skin was still taking place four hours after UV exposure was stopped.
“Half or more of this kind of DNA damage is not happening on the beach, it’s on the car on the way home,” Prof. Douglas Brash said.
The team hopes they can develop a sunscreen that combines the usual protection with absorbing any energy from the melanin.
Massachusetts Institute of Technology tops the world’s top 20 universities, according to the new QS World University rankings.
Harvard University comes second and UK’s University of Cambridge is in third position.
University College London (UCL) and Imperial occupied fourth and fifth places, with Oxford in sixth.
Universities in the United States made up the rest of the top 10.
Top 20 universities:
1. Massachusetts Institute of Technology (MIT)
2. Harvard University
3. University of Cambridge
4. University College London (UCL)
5. Imperial College London
Massachusetts Institute of Technology tops QS World University Rankings in 2013
6. University of Oxford
7. Stanford University
8. Yale University
9. University of Chicago
10=. California Institute of Technology (Caltech)
10=. Princeton University
12. Eth Zurich (Swiss Federal Institute of Technology)
13. University of Pennsylvania
14. Columbia University
15. Cornell University
16. Johns Hopkins University
17=. University of Edinburgh
17=. University of Toronto
19=. Ecole Polytechnique Fédérale de Lausanne
19=. King’s College London
A new study has showed that women who cycle regularly are at risk of decreased sensation in the pelvic region.
Scientists at Yale University found that female cyclists may experience less pleasure during sex if the handlebars of their bike are lower than the seat.
They learned that a low handlebar position puts extra pressure on nerves and blood vessels, or neuropathies, in the genital area.
The study reported that modifying a bicycle’s setup by raising its handlebars “helps alleviate neuropathies” in females.
The findings, which were published in the Journal Of Sexual Medicine, were based on analysis of 48 women who each rode at least ten miles per week, four weeks per month.
Researchers had each participant mount their own bike on a stationary machine.
Scientists at Yale University found that female cyclists may experience less pleasure during sex if the handlebars of their bike are lower than the seat
They were asked to speak out if they experienced “soreness, tingling and other sensations”.
Sensation in the woman’s pelvic floor was then measured by a researcher using a pressure map.
Genital sensation was “measured in microns using biosthesiometry measures of vibratory thresholds”.
The study explained: “Handlebars positioned lower than the saddle correlated with increased perineum saddle pressures and decreased anterior vaginal and left labial genital sensation.”
The research follows a 2006 study from the same university, which acknowledged an association between cycling and decreased genital sensation, but not a reason for it.
While the effects of bike-riding for long periods of time have widely been linked to male erectile dysfunction, effects on a woman’s sexual health are often overlooked.