Author Archives: curiouscat

Nature Recreation Declining

Glacier National Park photo by John Hunter

Photo looking north across Lake McDonald from my Village Inn balcony in Glacier National Park, by John Hunter.

Nature recreation worldwide — from camping, hunting and fishing to park visitation — has declined sharply since the 1980s
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The study examines data from the United States, Japan and Spain on everything from backpacking to duck hunting…that correlated a decline in visits to U.S. National Parks with an increase in television, video game and Internet use.
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The decline in some nature use seems to be accelerating, such as U.S. state park and national forest visits, as well as fishing. Others show a more steady decline, such as U.S. and Japanese national park visits and U.S. Bureau of Public Lands visits. Most reliable long-term per capita visitation measures of nature recreation peaked between 1981 and 1991. They’ve declined about 1.2 percent per year since then, and have declined a total of between 18 percent and 25 percent.
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Other research shows that the time children spend in nature — particularly the activities we looked at in this study – determines their environmental awareness as adults. We recently wrote a review paper looking at this phenomenon as well as at the effects of videophilia on childhood development. These effects are substantial and include obesity, attentional disorders, lack of socialization and poor academic performance.

I must say I am surprised by this. My visits to national parks have led me to believe the attendance was increasing but that seems to be wrong. The National Parks Service has a simple web tool to view visits to US national parks by year. Go visit great parks, here are some photos from my trips: Grand Teton National Park, Rocky Mountain National Park, Shenandoah National Park and Grand Canyon National Park.

Energy-Efficient Microchip

Team develops energy-efficient microchip

The key to the improvement in energy efficiency was to find ways of making the circuits on the chip work at a voltage level much lower than usual, Chandrakasan explains. While most current chips operate at around one volt, the new design works at just 0.3 volts.

Reducing the operating voltage, however, is not as simple as it might sound, because existing microchips have been optimized for many years to operate at the higher standard-voltage level. “Memory and logic circuits have to be redesigned to operate at very low power supply voltages,” Chandrakasan says.

One key to the new design, he says, was to build a high-efficiency DC-to-DC converter–which reduces the voltage to the lower level–right on the same chip, reducing the number of separate components. The redesigned memory and logic, along with the DC-to-DC converter, are all integrated to realize a complete system-on-a-chip solution.

One of the biggest problems the team had to overcome was the variability that occurs in typical chip manufacturing. At lower voltage levels, variations and imperfections in the silicon chip become more problematic. “Designing the chip to minimize its vulnerability to such variations is a big part of our strategy,” Chandrakasan says. “So far the new chip is a proof of concept. Commercial applications could become available “in five years, maybe even sooner, in a number of exciting areas”

The World’s Hottest Chili

The World’s Hottest Chili:

The standard measure for such things is the Scoville Heat Unit, or SHU, named after Wilbur Lincoln Scoville, a chemist who in 1912 developed a method of assessing the heat given off by capsaicin, the active ingredient in chili peppers. JalapeÃ±o peppers measure about 5,000 SHUs. The bhut jolokia tops a million.
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Food scientists speculate that hot chilies have an unexpected side effect that boosts their popularity. A publication of the Brooklyn Botanical Garden in New York described it this way: “When capsaicin comes into contact with the nerve endings in the tongue and mouth, pain messengers, called neurotransmitters, are sent to the brain in a panic. The brain, mistakenly perceiving that the body is in big trouble, responds by turning on the waterworks to douse the flames. The mouth salivates, the nose runs and the upper body breaks into a sweat. The heart beats faster and the natural painkiller endorphin is secreted. In other words, you get a buzz.”

Water: Supercool and Strange

Supercool, and Strange

As liquids go, water is a radical nonconformist—differing from other liquids in dozens of ways (see the latest count at www.lsbu.ac.uk/water/anmlies). Most famous among water’s peculiarities is its density at low temperatures. While other liquids contract and get denser as they cool toward their freezing points, water stops contracting and starts to expand. That’s why ice floats and frozen pipes burst.
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Water gets even weirder at colder temperatures, where it can exist as a liquid in a supercooled state well below its ordinary freezing point. Recent evidence suggests that supercooled water splits its personality into two distinct phases—another oddity unseen in other liquids. And last year, water surprised scientists yet again, when they found that at –63 degrees Celsius, supercooled water’s weird behavior returns to “normal.”

The Decoy Effect

The Decoy Effect, or How to Win an Election

The human brain, however, always seeks simple answers. Enter the third candidate. Huber told some people there was also a choice of a four-star restaurant that was farther away than the five-star option. People now gravitated toward the five-star choice, since it was better and closer than the third candidate. (The three-star restaurant was closer, but not as good as the new candidate.)

Another group was given a different third candidate, a two-star restaurant halfway between the first two. Many people now chose the three-star restaurant, because it beat the new option on convenience and quality. (The five-star restaurant outdid this third candidate on only one measure, quality.)

What the decoy effect basically shows is that when people cannot decide between two front-runners, they use the third candidate as a sort of measuring stick. If one front-runner looks much better than the third candidate, people gravitate toward that front-runner. Third candidates, in other words, can make a complicated decision feel simple.

Internet Undersea Cables

In a previously post we highlighted some of the engineering involved in fixing undersea cables and the challenges in laying internet fiber underwater. Given the recent news those posts might be of interest: Cut undersea Internet cables slow India’s connectivity

Early estimates suggested that half of India’s Internet capacity vanished after the first two cable lines were cut Wednesday. In other countries, such as Egypt, the figure was as high as 70 percent. The two Mediterranean cables cut Wednesday carry the bulk of the region’s Internet traffic
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Much of this traffic has now been rerouted along Pacific cables. Because of the redirected traffic, a third cable cut, discovered Friday in the Gulf region, has had no effect. Some 90 percent of India’s bandwidth has been restored and cable repairs are expected to take two weeks, but bad weather has prevented a repair ship from setting off to mend one of the cables.

For some businesses, the cut meant a slightly degraded service – poorer reception for call-centers that use Internet telephony, for example. But for larger businesses that carry the bulk of outsourcing from the United States and Europe, there was virtually no disruption.

“We have diversity in path and providers globally, and hence we have not lost any connectivity to our offices or customers,” according to an e-mailed statement by Infosys, one of India’s largest Information Technology companies.

While the initial reports talk of the cables being damaged by a ship anchor, at least one new report disputes that, Ships did not cut internet cable:

No ships were present when two marine cables carrying much of the Middle East’s internet traffic were severed, Egypt’s Ministry of Communications has said, contrary to earlier speculation about the causes of the cut.
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“A marine transport committee investigated the traffic of ships in the area, 12 hours before and after the malfunction, where the cables are located to figure out the possibility of being cut by a passing vessel and found out there were no passing ships at that time,” said the statement.

Treated Mosquito Nets Prevent Malaria

WHO Backs Free, Treated Mosquito Nets to Prevent Malaria

Long-lasting, insecticide-treated mosquito nets should be distributed free, rapidly and widely in malaria-endemic areas, World Health Organization officials said here Thursday, setting new guidelines for fighting the mosquito-borne disease around the globe.
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The WHO announcement was paired with what Kochi called “impressive” findings by Kenyan health authorities that widespread, free distribution of mosquito nets can effectively save children’s lives.

After several years of using a combination of free distribution and sales, the Kenyan government last year conducted a massive, almost military-style campaign to distribute without charge 3.4 million insecticide-treated mosquito nets over three days in 46 malaria-endemic districts across the country.

Among a monitored group of 3,500 children in four of those districts, the number sleeping under the nets increased nearly tenfold from 2004 to 2006, WHO said, citing Kenyan government figures. The result was 44 percent fewer deaths than among children not sleeping under nets. Insecticide-treated mosquito nets kill mosquitoes on contact. If enough nets are distributed and used, they can have a kind of collective impact of eradicating mosquitoes in a given area.

PLoS Medicine open access article: Increasing Coverage and Decreasing Inequity in Insecticide-Treated Bed Net Use among Rural Kenyan Children

Genetic Research Suggests Cats ‘Domesticated Themselves’

Why Do Cats Hang Around Us? (Hint: They Can’t Open Cans), Washington Post

The findings, drawn from an analysis of nearly 1,000 cats around the world, suggest that the ancestors of today’s tabbies, Persians and Siamese wandered into Near Eastern settlements at the dawn of agriculture. They were looking for food, not friendship.

They found what they were seeking in the form of rodents feeding on stored grain. They stayed for 12 millennia, although not without wandering off now and again to consort with their wild cousins. The story is quite different from that of other domesticated animals: cattle, sheep, goats, horses

Rainforests

John Hunter in Costa Rica

Facts about Rainforests by The Nature Conservancy

Covering less than 2 percent of the Earth’s total surface area, the world’s rainforests are home to 50 percent of the Earth’s plants and animals.
Seventy percent of the plants identified by the U.S. National Cancer Institute as useful in the treatment of cancer are found only in rainforests.
Less than one percent of the tropical rainforest species have been analyzed for their medicinal value.
Originally, 6 million square miles of tropical rainforest existed worldwide. But as a result of deforestation, only 2.6 million square miles remain.
At the current rate of tropical forest loss, 5-10 percent of tropical rainforest species will be lost per decade.
Every second, a slice of rainforest the size of a football field is mowed down. That’s 86,400 football fields of rainforest per day, or over 31 million football fields of rainforest each year.

Photo of John Hunter in Costa Rican rain forest, by Justin Hunter.

Teach Yourself Programming in Ten Years

Teach Yourself Programming in Ten Years by Peter Norvig

Get interested in programming, and do some because it is fun. Make sure that it keeps being enough fun so that you will be willing to put in ten years.
Talk to other programmers; read other programs. This is more important than any book or training course.
Program. The best kind of learning is learning by doing. To put it more technically, “the maximal level of performance for individuals in a given domain is not attained automatically as a function of extended experience, but the level of performance can be increased even by highly experienced individuals as a result of deliberate efforts to improve.” (p. 366)