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cvvt1986

A Holiday for Oil

Are we running out of oil?

http://podcast.sciam.com/earth/sa_e_podcast_081218.mp3

cvvt1986

Hanukkah is all about oil—and a miracle that purportedly stretched one day's worth of oil into light for eight days. The question is: will modern society have to do the same?

Our world relies on oil for everything: fuel, plastic even food. And with prices now plummeting one might predict a return to the age of abundant, cheap fossil fuel.

Not according to the International Energy Agency, which now predicts “peak oil” as early as 2020. Peak oil is the point at which the world's oil producers are drawing as much oil out of the ground as they will ever be able to. Paired with continued growth in demand from places like the U.S. and China, that's a recipe for much higher oil prices.

A majority of oil executives surveyed by the consulting firm Deloitte agree. They predict an end to cheap oil within the next 25 years--and an even larger majority think it will cease to be the cheapest energy source.

But rather than searching for ways to stretch the oil we still have--like a modern Hanukkah--it makes more sense to accelerate development of clean alternatives such as electric cars or biofuels from algae--and avoid dirty ones like turning coal or tar sands to liquid fuels.

As a Saudi oil minister once said: The Stone Age didn't end for a lack of stones. And the Oil Age may not end for lack of oil.

—David Biello

illusory87

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cvvt1986

Fruit Fly Immunity Stronger While Sleeping

http://podcast.sciam.com/daily/sa_d_podcast_081222.mp3

cvvt1986

For those of you who’ve spent many of your waking hours this winter washing your hands and fretting about getting sick, you might be better off just staying in bed. Because scientists from Stanford University have found that the immune system works best after dark.

The scientists were studying fruit flies, which are active at dawn and dusk, and sleep through the night like you and me. The circadian rhythm that tells these critters, and many others, when to snooze and when to cruise, controls lots of bodily functions. So the scientists got to wondering whether it also regulates the immune system and the fly’s ability to fight infections. Yes, even fruit flies can catch some pretty nasty bugs. Which the scientists proceeded to demonstrate.

They took a bunch of flies and infected them with some unsavory bacteria. Half the flies were infected while they slept, half while they were awake. Turns out that the flies that were infected at night were better able to battle their bugs than flies who got sick during the day, results presented at the American Society for Cell Biology meeting in San Francisco on December 14th. Whether human immunity is also better during sleep isn’t yet known. But Shakespeare might have been onto something when he called sleep “nature’s soft nurse.”

—Karen Hopkin 

cvvt1986

Brain Activity Altered during Religious Experience

 

 

http://podcast.sciam.com/daily/sa_d_podcast_081224.mp3

cvvt1986

In America there’s a feeling of Christmas. But that’s not the only winter holiday going on. Jews are lighting Hanukkah candles, Muslims recently feasted on Eid al-Adha, and pagans celebrated the solstice. So it’s a good time for researchers to consider spirituality—from a scientific point of view.

One experience central to major religions around the world is that of transcendence, the idea of almost losing a sense of self to the feeling that there’s something bigger out there. Now scientists at the University of Missouri say they’ve located that experience in our brains. All the people studied, from Buddhist monks in meditation to Francescan nuns in prayer, experience this transcendence. And they all have decreased activity in the right parietal lobe of the brain. That area has to do with senses such as orienting yourself in the space around you. The study was published in Zygon: Journal of Religion & Science.

Interestingly, people with injuries to the right parietal lobe report increased levels of spiritual experiences. The researchers are quick to say that this connection doesn’t minimize the role of religion, and that religious or spiritual experiences might decrease activity in that region and thus increase that special feeling of transcendence. Just in time for the holidays.

—Cynthia Graber 

cvvt1986

Fasting May Equal Calorie-Restricted Diets

http://podcast.sciam.com/daily/sa_d_podcast_081226.mp3

cvvt1986

Sometimes it’s not what you eat, but when you eat it. At least when it comes to longevity diets. For some time, scientists have known that animals kept on a strict diet live longer than their well-fed peers. But this Methuselah meal plan is no ordinary just-say-no-to-that-second-slice of pie kind of diet. To reap the life-extending benefits, some of these animals cut their calorie consumption in half. Such a diet might be do-able for captive mice and monkeys, but it would be a tough sell for people.

Then, five years ago, studies in mice suggested that intermittent fasting would work just as well. These mice abstained from eating every other day, and lived longer then their gluttonous comrades—without really skimping on the total calories they consumed.

Now, scientists at Kyoto University have found the same thing in worms that fasted every third day. And they found a gene that regulates the effect, results reported in the journal Nature. Like the mice, these fasting worms did not cut their total calorie intake. But they boosted their lifespan by 50 percent, and showed fewer signs of physical decline than their peers. So go ahead, enjoy that extra slice of pie. Because tomorrow’s another day. To not eat.

—Karen Hopkin 

illusory87

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