The good news for public health is that there have been significant decreases in past-month cigarette smoking by young adults and recreational use of opioid medications in the past year compared to 10 years ago. The same goes with alcohol, which is still the most used substance but has seen declines in past-year, past-month, and daily drinking.

A common first step in embryonic development is that an egg meets a sperm but in a Weizmann Institute of Science study published today in Cell, researchers have grown synthetic embryo models of mice outside the womb by starting solely with stem cells cultured in a petri dish.

Without the use of fertilized eggs.

Before every Marvel film premiere, comic books related to the characters almost always rise in value. People who speculate buy them from sellers. It's a bad idea.

In other parts pf culture, people who read about trendy topics like working-from-home and the metaverse and buy exchange traded funds (ETFs) will also likely be disappointed. Researchers found that ETFs based on these and similar hot topics earn an average return about 30 percent lower than more diversified funds over the five years after they are launched.

To most physicists, time is a relative construct. A clock changes position in three real dimensions, the earth rotates. If the effects in the real world change, like gravity, so does the perception of time. That does not make time a 'fourth' dimension outside stories.

Yet a few theoretical physicists argue that because time does march on, it is like an arrow. This 'arrow of time' would move into the future, and to bolster their idea they invoke the second law of thermodynamics: the principle that microscopic arrangements of physical systems tend to increase in randomness, moving from order to disorder. The more disordered a system becomes, the more difficult it is for it to find its way back to an ordered state, and the stronger the arrow of time.

The history of humans is a history of expansion, from the recesses of Africa outward across the world. No one is really a native and yet everyone is, because all humans were first an invasive species but if you are born in a place, you are then native. 

Some will claim their ancestors lived in a place 12,000 years ago, but unless they had an individual genomic analysis it's no more valid than saying they were descended from Genghis Khan, yet science is converging on ways to go beyond the silly '12 percent Irish' claims based on 23andMe or Ancestry and really determine if your ancestors were as close to the first humans as can exist.

If you get sleepy in the middle of hot days, you are not alone. You are not even alone in the animal kingdom.

Biology may be behind it.

We know that many people have a harder time sleeping in the summer and be slow to get out of bed on colder mornings and new study hopes to connect sensory neurons and neurons that control this cycle.

The work is only in fruit flies, so it goes in the exploratory pile despite the hyper-coverage such studies get in corporate media, but they found that fruit flies are pre-programmed to take a nap in the middle of the day. They believe there is a brain thermometer only active in hot temperatures.