The Sinclair group's NAD paper drew attention partly because it showed a novel way that NAD and sirtuins work together. The researchers discovered that cells' nuclei send signals to mitochondria that are needed to maintain their normal operation. SIRT1 helps insure the signals get through. When NAD levels drop, as they do with aging, SIRT1 activity falls off, which in turn makes the crucial signals fade, leading to mitochondrial dysfunction and all the ill effects that go with it.

Test-tube and rodent studies also suggest that pterostilbene is more potent than resveratrol when it comes to improving brain function, warding off various kinds of cancer and preventing heart disease.

Hedonic well-being comes from an experience a person seeks out that gives them pleasure.

Eudaimonic well-being is a kind of happiness that comes not from consuming something but from a sustained effort at working toward something bigger than you.

they can and do influence each other, so it has been hard for scientists to measure which kind has had a greater positive influence on someone's physical or psychological well-being.

there is an increased expression of genes involved in inflammation and a decreased antiviral response. People who are subjected to long periods of stress have white blood cells that make slightly more pro-inflammatory proteins on a constant basis.

Bottom line? Happiness that comes from working for the greater good has a much more positive genetic impact.

The people who found happiness by pursuing a greater good had a lower level of this inflammatory gene expression and strong antiviral and antibody gene expression.

"Possibilities include a broader set of health behaviors than we measured (such as maintaining a healthy weight and adherence to medical advice), and greater resilience, sense of mastery and will to live among those who feel younger than their age," the study concludes.

"Research is showing us that personality can so be tied to your destiny,"

And so Operation Peacemaker was born. Loosely based on an academic fellowship, the ONS program invites some of the most hardened youth into the fold: often teenage boys suspected of violent crimes but whom authorities don't have enough evidence to charge criminally.

They are hooked up with mentors -- the reformed criminals-turned-city workers -- who offer advice, guidance and support to get jobs. If the fellows show good behavior after six months, they can earn a stipend of up to $1,000 a month.

In the media, the fellowship is often dubbed "cash for criminals," which makes Boggan's eyes roll. He laughs because, although it's true, the program is so much more. And it's predicated on the most basic of human elements: "We harass them with love and kindness."

Kimberley Ann Perkins O'Connor, who captured part of the incident on her phone, told CNN she overheard the boy joking to his mother about going into the water. Then, suddenly, there he was, being dragged by Harambe.

Some suggested the boy's parents should be held criminally responsible for the incident. An online petition seeking "Justice for Harambe" earned more than 100,000 signatures in less than 48 hours.

"We had a very difficult situation and we made a difficult call at the end. I'm not here to point fingers about fault," he said.

"We live in the real world, we make real decisions. People and kids can climb over barriers. We work hard to make sure this zoo is safe. People can climb over barriers, that's what happened."

Western lowland gorillas are critically endangered in the wild, numbering fewer than 175,000, according to the zoo. An additional 765 gorillas dwell in zoos worldwide.

Harambe was put down, a decision that left many wondering if the zoo was too quick to shoot.

Although it was the first incident of its kind at Cincinnati Zoo's Gorilla World exhibit since it opened in 1978, similar cases have occurred with very different outcomes.

The footage shows Jambo, a male gorilla, approaching the boy as if to check on him, extending a hand to stroke his back. When Merritt comes to, wailing, Jambo, seemingly startled by the cries, sets off in a different direction. Zookeepers immediately move in to save the boy.

This time, a female gorilla named Binti Jua picked up the unconscious boy, while carrying her own infant on her back, and guarded him from other gorillas.

not always the gentle giants the world saw in these two cases -- the animal advocacy group People for the Ethical Treatment of Animals said the larger concept of zoos is the root of the problem.

Maynard said the zoo plans to reopen the exhibit to the public after a thorough assessment.

If you enjoy being able to speak your mind publicly and practice (or abstain from practicing) the religion of your choice, please think of this Memorial Day as more than a beachside, grill-side day off from work. Attend a local ceremony; thank a veteran; reach out to the family of a deployed or wounded service member.

the world of business is more international and companies’ reaches are more global than ever before, so you might actually find that your familiarity with, and fluency in, another country could be a résumé plus.

Inevitably, some of those initial steps will have been influenced by seemingly trivial random events. So it is reasonable to conclude that virtually all successful careers entail at least a modicum of luck.

One’s date of birth can matter enormously, for example. According to a 2008 study, most children born in the summer tend to be among the youngest members of their class at school, which appears to explain why they are significantly less likely to hold leadership positions during high school and thus, another study indicates, less likely to land premium jobs later in life. Similarly, according to research published in the journal Economics Letters in 2012, the number of American chief executives who were born in June and July is almost one-third lower than would be expected on the basis of chance alone.

To acknowledge the importance of random events is not to suggest that success is independent of talent and effort. In highly competitive arenas, those who do well are almost always extremely talented and hard-working.

Such expertise comes not from luck but from thousands of hours of assiduous effort.

Being born in a good environment is one of the few dimensions of luck we can control — that is, at least we can decide how lucky our children will be.

The unlucky population is growing, and its luck is getting worse.

Evidence from the social sciences demonstrates that beyond a certain income threshold, people’s sense of well-being depends much more on their relative purchasing power than on how much they spend in absolute terms. If top tax rates were a little higher, all homes would be a little smaller, all cars a little less expensive, all diamonds a little more modest and all celebrations a little less costly. The standards that define “special” would adjust accordingly, leaving most successful people quite satisfied.

Merely prompting people to reflect on their good fortune tends to make them more willing to contribute to the common good, according to a 2010 study published in the journal Emotion.

A five-member conservative or liberal majority on the Supreme Court can impose a partisan political agenda on the country without too much difficulty, often with one key justice dictating the results. With eight justices equally divided among conservative and liberals, the court can only act decisively when at least one justice switches sides. This is a state of affairs to be celebrated, not lamented, and may be appreciated when the court is fully staffed again.