As a new Roman emperor, your risk of death was high, but it declined as time went on, according to a new analysis. And over 70 rulers, the progression was predictable. 

Historical records show that of 69 rulers of the unified Roman Empire, 43 (62 percent) suffered violent deaths - assassination, suicide or combat. Historical accounts typically examine each death as a single, random event alongside individual contributing factors such as allegiances and wealth. The military got a bonus from a new Emperor so there were periods when turnover was linked to the financial effect, for example.

Though young people are able to obtain alcohol and drink it, their ability to buy alcohol at point of sale is almost nonexistent. That is not the case with recreational cannabis, where early adopter states have a shocking 37 percent rate of youth being able to purchase marijuana. In  recreational only cannabis stores, 71 percent were able to purchase without a valid ID showing they were of legal age. 

Sperm quality can be reduced by several lifestyle factors, like obesity and related diseases such as type 2 diabetes, but a new examination of epigenetic phenomena - gene expression changing even if the DNA sequence is not changed -  finds that even diet can impact sperm quality, and in just two weeks.

The concern is that such epigenetic changes might be able to lead to properties being transferred from a parent to offspring via the sperm or the egg. 

Any time is a good time to start exercising but a great time to start exercising is today. Share this article on Facebook first, though. 

Don't be intimidated by those people who hiss about Crossfit or their Peloton, a new study shows you have the same ability to build muscle mass as highly trained master athletes of a similar age.

Navan Fort, the legendary capital of Ulster. has long been considered a site of ritual gatherings.  Excavations have uncovered a huge 40-yard diameter building and a barbary ape cranium, likely from at least as far as Iberiam along with remnants of pigs, cattle and sheepfrom across Ireland, perhaps being reared as far afield as Galway, Donegal, Down, Tyrone and Antrim. 

That means Iron Age communities were very mobile at holiday time, their own version of driving for Christmas. 

Light propagation usually goes both ways; it is reciprocal in that the trajectory of light traveling one direction is identical in the opposite direction.

Isolators and circulators, which make light propagate only in one direction, are vital building blocks in many modern laser and communication systems, but are almost exclusively based on the magneto-optic effect, making devices bulky and difficult for integration. A magnetic-free route would be a great breakthrough for many optical applications.