It isn't just human adults who regard youth as disease factories, in many species the young are often more susceptible to infection than adults, even after accounting for prior exposure to infection.

Evolution has an explanation for that. But like a lot of things in evolution, it may seem puzzling.

It shouldn't make sense, since dying young or becoming infertile due to infection means organisms will be unable to reproduce, but many species may have evolved to prioritize growth over immunity while maturing. And that complexity may be why immunity varies with age in different species.

A new study shows that smokers who switch to nicotine vapor alternatives (e.g. e-cigarettes or iQOS) may be better able to stay smoke-free in the long term - even if they didn't set out to quit smoking. 

And that even people who didn't want to stop smoking have eventually quit because they found vaping more enjoyable.  E-cigarettes contain nicotine, which is the addictive component of cigarettes also, but it's toxic chemicals in smoke that cause the harms of smoking. That is why e-cigarettes have caught on as an aid to help people quit smoking for good, whereas patches and gums are only effective for about 10 percent. 

If you want to map opioid prescription use, you can do it, right down to Congressional district. The highest rates are in the southeastern U.S., Appalachia and the rural west, all areas where there is more manual labor, according to an analysis in American Journal of Public Health.

The authors believe this could help policy makers at the federal and state level better target intervention and prevention strategies, though statistics have shown prescription use is not the problem, illegal recreational use is.

Neuroscientists believe that people's earliest memories date from around three to three-and-a-half years of age but many people report memories much earlier than that. It's likely just as fake as claims of repressed memories from the 1980s. 

At least according to surveys, which are just as unreliable as science claims about memory. 

Survey results of people's first memories found that 38.6 percent of 6,641 people claimed to have memories from two or younger, with 893 people claiming memories from one or younger. This was particularly prevalent among middle-aged and older adults.

Over 25 years ago, members of Congress saw statistics showing that U.S. people with college educations made more money, and they declared that college education should be a right. The solution was indicative of government - change student loans to being unlimited.

Are young people all making more money? No, they are buried in debt, but schools that were once foundering are now doing quite well. An entirely industry built up around universities for under-achieving students with money. And on the other end, credentialism came into play. A bachelor's degree became what a high school diploma was. 

Social media is king. It can run pizza chain founders out of their companies, it can be used by anti-science activists to mobilize well-meaning science advocates against other science advocates, but what it can't do is change human nature. And human nature says people will visit those nearby.

Even when people have well-connected social networks state lines, they are still most frequently interacting with people who are geographically close. Except in Los Angeles. Apparently everyone is looking for a reason to leave Los Angeles. 

DNA methylation is a molecular process that helps enable our bodies to repair themselves, fight infection, and get rid of environmental toxins, but new research has shown one way it can go awry: Obesity. 

Scholars identified how DNA methylation is associated with a condition known as non-alcoholic fatty liver disease (NAFLD), which can lead to liver cirrhosis and death. 
Their evidence is that DNA methylation has a role in the initiation of NAFLD-related fibrosis, 

Between 1999-2016, young adults had substantially higher deaths from cirrhosis in 49 of 50 U.S. states. The deaths linked to the end stages of liver damage jumped by 65 percent with alcohol a major cause in adults age 25-34.

The data published in BMJ shows young adults experienced the highest average annual increase in cirrhosis deaths -- about 10.5 percent each year and driven entirely by alcohol-related liver disease, the authors say. Researchers studied the trends in liver deaths due to cirrhosis by examining death certificates compiled by the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research project.

Up-and-down ripples, swings that rise and recede like the teeth on a saw blade, are found in everything from stock prices on Wall Street to ocean waves; and they occur periodically in the temperature and density of the plasma that fuels fusion reactions in doughnut-shaped facilities called tokamaks. If the swings combine with other instabilities in the plasma they can halt the reactions. Why some plasmas are free of sawtooth gyrations has long puzzled physicists. 

If you want to know how to do time travel, ask a mathematician. If you want to show how math is not science, but is instead the language of science, hand those equations to a physicist.