It's been around for decades and it's probably in your diet soda - for a little while longer anyway. PepsiCo announced recently it was removing the artificial sweetener aspartame from its Diet Pepsi products in the U.S. starting in August.

The company cited consumer concerns about the chemical's safety.

So this week, Reactions answers the question, "Is aspartame safe?"

The prevalence of smoking among undergraduate nursing and physiotherapy students in Spain decreased from 29.3% in 2003 to 18.2% in 2013. Many of the students remained unaware of the link between smoking and diseases such as bladder cancer or the negative health effects of second-hand smoke, which points to a significant deficiency in undergraduate training.

The majority of nursing and physiotherapy students recognized that healthcare professionals were role models in society, noted Dr. Beatriz Ordás, lead author of the Journal of Advanced Nursing study.

The recent craze for human breast milk amongst certain fitness communities and fetishists is ill advised.

A team of scientists and engineers at The University of Texas at Austin has identified the first sensor of the Earth's magnetic field in an animal, finding in the brain of a tiny worm a big clue to a long-held mystery about how animals' internal compasses work.

Animals as diverse as migrating geese, sea turtles and wolves are known to navigate using the Earth's magnetic field. But until now, no one has pinpointed quite how they do it. The sensor, found in worms called C. elegans, is a microscopic structure at the end of a neuron that other animals probably share, given similarities in brain structure across species. The sensor looks like a nano-scale TV antenna, and the worms use it to navigate underground.

A hereditary autoimmune disease that was thought to be exceedingly rare may have a less severe form that affects one in 1,000 people or even more.

The results suggest that a number of different autoimmune diseases and syndromes may be tied to mutations in a single gene. Among other things, these findings, combined with other research in the Weizmann lab, may help provide new means of diagnosing and treating autoimmune disorders.

Richard Dawkins and Francis Collins have dramatically different roles when it comes to science. One is a science popularizer and extremely anti-religious while one runs the $30 billion National Institute of Health and is a religious believer, but also writes popular science editorials and uses Twitter.

Which one would you guess most people can name?

The recent commitments by the leaders of G7 nations to reduce emissions of carbon dioxide to 40-70% below current levels by 2050, and to eliminate the use of fossil fuels altogether by 2100, have raised several questions.

Are these objectives feasible? Are they consistent with national commitments? Are they sufficient to stabilize the global climate without dangerous rates of warming? And are they anything new?

In the blockbuster "Jurassic World", actor Chris Pratt joins forces with a pack of swift and lethal velociraptors. "Velociraptor belongs to a group of predatory dinosaurs called the deinonychosaurs, or simply the 'raptors'," says University of Alberta paleontologist Scott Persons. "Raptors are characterized by particularly nasty feet. Their big toes each bore an enlarged and wickedly hooked talon, which makes raptors well suited for Hollywood fight scenes."

Persons and University of Alberta alumnus Lida Xing are part of the research team that has just documented a rich fossil footprint site in central China, which contains the tracks of several kinds of dinosaurs, including raptors. From these tracks, the team has gained new insights into raptor locomotion. 

Stem cells are especially sensitive to oxygen radicals and antioxidants shows new research from the group of Anu Wartiovaara in the Molecular Neurology Research Program of University of Helsinki.

Mitochondria are cellular power plants that use oxygen to produce energy. As a by-product they produce reactive oxygen. Excessive oxygen radicals may cause damage to cells but they are needed in small quantities as important cellular signaling molecules. One of their main functions is to control function of stem cells. Antioxidants are widely used to block the damage caused by reactive oxygen. To enhance their effect some new antioxidants are targeted to accumulate into mitochondria.

Media are important. Especially the media we trust. One might express the effect of a piece of journalism (J) about, say, a particular drug or food, as a factor of media authority (A), multiplied by the size of audience (D), divided by the availability of credible alternative sources (S).

The more of the latter which are accessible to the audience, and thus the greater the challenge to the “truthiness” of (J), the lesser the impact on individual and collective behavior. Where people trust the news source, and the issue is complex, and alternative analyses are not easily sourced, the effect is greater.