Varices, commonly called varicose veins, are a cosmetic problem if they occur as spider veins but in their advanced stage they pose a real health threat. In those patients, the blood is no longer transported to the heart unhindered but instead pools in the veins of the leg because the vessel walls or venous valves no longer function adequately.

Estimates show that 2010 was by far a record year for CO₂ emissions from fossil-fuel combustion and cement manufacture. Globally 9,139 Teragrams, a teragram is a million metric tons, of oxidized carbon (Tg-C) were emitted from these sources.

Converted to carbon dioxide, so as to include the mass of the oxygen molecules, this amounts to over 33.5 billion metric tons of carbon dioxide. The increase alone is about 512 Tg-C, or 5.9%, over the 2009 global estimate. The previous record year was 2008, with 8,749 Tg-C emitted; the 2010 estimate is about 104.5% of that, or 391 Tg-C more.

Physical activity is always good for you but a new analysis says it may patients reduce their risk of developing glaucoma. Higher levels of physical exercise appear to have a long-term beneficial impact on low ocular perfusion pressure (OPP), an important risk factor for glaucoma.

The analysis examined the relationship between physical activity and current OPP in 5,650 men and women aged 48-90 who live in the U.K. and were part of initial cohort from 1993-1997.

Chinese researchers have created a hypothesis for a quantum cloning machine able to produce several copies of the state of a particle at atomic or sub-atomic scale, or quantum state, which if produced could have implications for quantum information processing methods such as encryption systems.

Quantum cloning is difficult because quantum mechanics laws only allow for an approximate copy—not an exact copy—of an original quantum state to be made, as measuring such a state prior to its cloning would alter it. In their study, they demonstrate that it may be possible to create four approximate copies of an initial quantum state, a process called asymmetric cloning.

Prevailing wind shear patterns prohibit cyclones in the Arabian Sea from becoming major storms but a new study says winds are weakening and that has enabled the formation of stronger cyclones in recent years -- including storms in 2007 and 2010 that were the first recorded storms to enter the Gulf of Oman.

 Black holes are invisible but the forces they unleash cause some of the brightest phenomena in the Universe; quasars. The gravitational lensing effect of stars in a distant galaxy and the Hubble Space Telescope have teamed up to observe a quasar accretion disk, the brightly glowing disk of matter that is slowly being sucked into its galaxy’s central black hole, which heat up and emit extremely bright radiation as they 'enter'.

Result: Researchers were able to directly measure the disk’s size and plot the temperature across different parts of the disc; a level of precision equivalent to spotting individual grains of sand on the surface of the Moon.