From its role in kissing to mythological healing powers, mistletoe's roots run deep. This novella was the earliest and most popular of Dickens' Christmas stories. The kissing under mistletoe (left) and evergreen decoration hanging from the ceiling are vestiges of pre-Christian winter rites. Breakthroughs, discoveries, and DIY tips sent every weekday. It's hard to imagine a holiday season without Bing Crosby's Christmas standard Originally written from the perspective of a soldier stationed overseas during World War II, his longing for the simple comforts of home and reconnecting with his loved ones at Christmas is almost palpable: " Mistletoe just inexplicably feels familiar. Every December, the evergreen sprig s that spent the offseason hidden in our subconscious are suddenly all around us. Mistletoe is the long-lost acquaintance that we instantly recognize and embrace, yet whose backstory has been lost to us. "When I talk to people about parasitic plants, I know mistletoe is the one that they'll immediately recognize even if they don't really know it's a parasite," Virginia Tech plant biologist Jim Westwood tells . Author Washington Irving, best known for The Legend of Sleepy Hollow and is often credited with helping popularize the parasitic evergreen shrub in the United States. He wrote about the plant in an 1820 collection of short stories, but the roots of mistletoe go much deeper elsewhere in the world. Dating back to Ancient Greece and Rome, leafy mistletoe has long excited the imagination. Mistletoe served as a centerpiece of Celtic Rituals and Norse myths, where it bestowed life and fertility and served as an aphrodisiac, a plant of parley, an antidote for poisons, and a means of safe passage to and from Hades. According to The Living Lore, since the plant can thrive in the high branches of its host without soil, "many cultures saw mistletoe as a sacred plant, existing in liminal spaces between life and death, earth and sky, and human and divine." In Old Norse mythology, Baldr, the son of the god Odin and the goddess Frigg, was slain with a mistletoe spear. Some interpretations suggest that, "kissing under the mistletoe symbolizes forgiveness, echoing Frigg's grief and eventual reconciliation with the plant." Many early physicians and scientists saw mistletoe as a cure-all for the woes of the world. It was used to treat various diseases and conditions including epilepsy, infertility, and ulcers. In Pliny's, the writer and physician describes the Celtic ritual of oak and mistletoe. High priests dressed in white harvested mistletoe with golden sickles from the branches of sacred oak trees to make an elixir that could counteract any poison and render any barren animal fertile. "It's easy to imagine how people become fixated on mistletoe plants," says Westwood. "It stays green all winter growing in its host tree.

Real-time strategy is having a moment. And gaming's largest companies, including Microsoft and Tencent, are bankrolling studios behind new RTS entries like Age of Empires IV, which is set for release on October 28. This resurgence is good news for fans of real-time strategy games, but the genre must adapt to tastes of modern gamers. Fortunately, the developers behind tomorrow's blockbuster real-time strategy games are mindful of the genre's past mistakes. The seed of the real-time strategy genre was planted when Chris Crawford published a treatise on the future of real-time gaming, titled "The Future of Computer Wargaming," in the debut winter 1981 issue of Computer Gaming World.

How to estimate heterogeneity, e.g. the effect of some variable differing across observations, is a key question in political science. Methods for doing so make simplifying assumptions about the underlying nature of the heterogeneity to draw reliable inferences. This paper allows a common way of simplifying complex phenomenon (placing observations with similar effects into discrete groups) to be integrated into regression analysis. The framework allows researchers to (i) use their prior knowledge to guide which groups are permissible and (ii) appropriately quantify uncertainty. The paper does this by extending work on "structured sparsity" from a traditional penalized likelihood approach to a Bayesian one by deriving new theoretical results and inferential techniques. It shows that this method outperforms state-of-the-art methods for estimating heterogeneous effects when the underlying heterogeneity is grouped and more effectively identifies groups of observations with different effects in observational data.

Driverless vehicles will face a'testing' 200-mile (320km) journey across the UK next year. The autonomous cars will have to contend with challenges such as winding country lanes, motorways and roundabouts, in an effort to test their systems. The nationwide test, dubbed HumanDrive initiative, is designed to put the computer-controlled cars through their paces in'live traffic and natural conditions'. The HumanDrive initiative hopes to put the computer controlled cars through their paces in'live traffic and natural conditions' on a 200-mile (320 km) road test of the driverless cars The UK wants to get driverless cars on the road by 2021. However, British roads present a number of unique challenges that autonomous driving systems are unlikely to be prepared for after testing in the United States.