Category Archives: Education

Nectar-Feeding Bats

Why Nectar-Feeding Bats Need A ‘Power Drink’ To Fly

Nectar-feeding bats burn sugar faster than any other mammal on Earth
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“We found that nectar-feeding bats made use of the sugar they were drinking for their metabolism within minutes after drinking it, and after less than half an hour they were fuelling 100% their metabolism from this source. For comparison, the highest rates reported in humans are for athletes who can fuel up to 30% of their metabolism directly from power drinks,” they say.
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Small nectar-feeding bats have among the highest metabolic costs among mammals, and mostly eat a diet low in fat and protein but rich in sugars. Metabolising these sugars immediately they are consumed saves the costs of converting them to and from storage.”

In a second experiment, Voigt and Speakman measured how fast the bats used their meagre fat stores. “We found the bats depleted almost 60% of their fat stores each day, but even this phenomenal rate was still barely enough to sustain their metabolism when nectar was absent. This underlines how accurately these bats must balance their energy requirements every day and how vulnerable they are to ecological perturbations that might interrupt their fuel supply for even a short period,” they say.

Nectar-feeding bats live in south and central America and are among the smallest of all living mammals, weighing less than 10g. They feed at night and can ingest up to 150% of their body weight as nectar.

That really is amazing.

Young Engineers Build Bridges with Spaghetti

Young engineers build bridges with spaghetti:

Proving that spaghetti is not just for dinner, the students of Johns Hopkins University’s Engineering Innovation summer program used the noodles to build intricate, miniature bridges and then wrecked them — all in the name of science. On Friday afternoon, the eight high school students participating in the competition pitted their engineering know-how against one another to see whose bridge could hold the most weight before splintering into pieces. The competition closed out four weeks of study under the summer program, which was taught by Muhammad Kehnemouyi, a full-time physics professor at Montgomery College, and Fred Katiraie, a full-time math professor at Montgomery College.
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The last team to go consisted of Sruti Bharat, 17, of California, Rohan Bhale, 15, of Olney, and Justin Yin, 17, of Wheaton. The group put weight after weight on the bridge and attached another chain to add more weights, but the bridge remained in one piece.

After adding all the weights available to them, Katiraie ran into another room to retrieve more. The team’s bridge held almost 60 times its actual weight before splintering.

Bacteria Frozen for 8 Million Years In Polar Ice Resuscitated

Eight-million-year-old bug is alive and growing

Kay Bidle of Rutgers University in New Jersey, US, and his colleagues extracted DNA and bacteria from ice found between 3 and 5 metres beneath the surface of a glacier in the Beacon and Mullins valleys of Antarctica. The ice gets older as it flows down the valleys and the researchers took five samples that were between 100,000 and 8 million years old.

They then attempted to resuscitate the organisms in the oldest and the youngest samples. “We tried to grow them in media, and the young stuff grew really fast. We could plate them and isolate colonies,” says Bidle. The cultures grown from organisms found in the 100,000-year-old ice doubled in size every 7 days on average.

Whereas the young ice contained a variety of microorganisms, the researchers found only one type of bacterium in the 8-million-year-old sample. It also grew in the laboratory but much more slowly, doubling only every 70 days.

Related: What is an Extremophile?

Harvard Course: Understanding Computers and the Internet

Harvard Extension School – Computer Science E-1: Understanding Computers and the Internet

This course is all about understanding: understanding what’s going on inside your computer when you flip on the switch, why tech support has you constantly rebooting your computer, how everything you do on the Internet can be watched by others, and how your computer can become infected with a worm just by turning it on. In this course we demystify computers and the Internet, along with their jargon, so that students understand not only what they can do with each but also how it all works and why. Students leave this course armed with a new vocabulary and equipped for further exploration of computers and the Internet. Topics include hardware, software, the Internet, multimedia, security, website development, programming, and dotcoms. This course is designed both for those with little, if any, computer experience and for those who use a computer every day.

Nice job. via: Learn How The Darn Thing Works … from Harvard

Related: University of California, Berkeley course videos – Technology Talks at Google – Engineering and Science Webcast Libraries – Lectures from the Stanford Linear Accelerator Center

Aerogels – Cool Substances

First Prize for Weird

A solid that’s up to 99 percent gas, it is rigid to a light touch, soft to a stronger one, and shatters like glass if it’s put under too much pressure too quickly; it’s one of the most enigmatic of materials, as well as one of the most versatile.

It can withstand the heat of a direct flame; engineers use it for insulation on oil rigs and for warmth in the insoles of hiking boots worn in the coldest temperatures on Earth. NASA uses it to trap comet dust blowing through the universe at six kilometers per second.
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Nicknamed “frozen smoke” after its ethereal appearance, aerogel is neither frozen nor smoke. It’s also surprisingly low tech—it’s been known since 1931
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Together, these ingredients can form a structure that chemically resembles glass but is so full of whorls and crevices that one cubic centimeter has a total surface area equal to a football field’s. The lightest-weight solid in the world, aerogel weighs 1.2 milligrams per cubic centimeter—barely more than the air molecules around it. In fact, the material itself is almost entirely made of air, like a sponge that consists mostly of holes. Don’t let its lightness fool you: it’s strong. NASA photos show two grams of the material easily supporting a 2.5-kilogram brick.
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And because the aerogels pack an enormous surface area into a tiny volume, small pieces can clear out many liters of water. Kanatzidis’s aerogels sopped up so much mercury that they diluted a solution of 645 parts per million down to 0.04 parts per million. They had similar effects on lead and cadmium, two other pollutants.

The new aerogels aren’t ready for widespread use: they’re made with platinum, so they’re extraordinarily expensive. But if other metals can be used to make them instead (Kanatzidis says they can), chunks of them could be dropped into polluted water, removing contaminants.

Cool. NASA Aerogel FAQ

Authors of Scientific Articles by Country

The United States National Science Foundation published – Changing U.S. Output of Scientific Articles: 1988–2003.

In an unexpected development in the early 1990s, the absolute number of science and engineering (S&E) articles published by U.S.-based authors in the world’s major peer-reviewed journals plateaued.
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The unprecedented plateau in the number of U.S. S&E articles should not be confused with a decades-long and familiar decline in the U.S. share of the world’s S&E articles. As other states built up their S&E capabilities, the U.S. share of the world’s articles in natural sciences and engineering dropped from 38% in 1973 to 28% in 2003. This decline in share is not surprising, nor has it been viewed as a cause for concern. By many measures, including articles published in peer-reviewed journals, the United States has been the world’s leading scientific nation for decades and remains the world’s leading scientific nation.
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Although the U.S. share of the world’s influential articles dropped substantially, the United States remained dominant in this area. At the end of the period studied, U.S. institutions were at least partially responsible for half of the world’s influential articles; no other major publishing center approached this figure. Moreover, compared with other major publishing centers, a considerably higher percentage of total U.S. output was classified as influential.

NSF includes a great deal of interesting data along with commentary. One compelling area is that of the location of authors of the top 1% of the most cited papers. The USA leads with 64.6% in 1992 and 56.6% in 2003. European Union-15 (15 countries for this measure) 23.3% to 27.7% (interesting, not what I would have predicted – which would have been a decline, though a small one). Japan 4.2% to 5.3%. East Asia – 4 (China, Singapore, South Korea, and Taiwan) from .1 to 1.1% (and rising rapidly – .5% in 2001 to .8% in 2002) – interesting but not so surprising, basically what I would expect – rapid gains. All other countries: 7.8% in 1992 and 9.3% in 2003. I predict these figures will have to break out India sometime in the next 10 years – I wish they did now though I expect it is a fairly low figure. China will also be reported separately, I believe.

The NSF data includes all sorts of great stuff. For the same top 1% of cited articles by topic East Asia – 4 in Engineering/Technology: 1992 .9% – 2003 7.2% in Social Sciences 0.0% to .6% in Mathematics 1.3% to 5.6%. In Engineering/Technology the USA dropped from 63.3% to 45.4%.

This is more data supporting what I have said before Science Excellence and Economic Benefits:
Continue reading →

Where is “Everybody”

The Fermi Paradox: Back with a vengeance

The Fermi Paradox is the contradictory and counter-intuitive observation that we have yet to see any evidence for the existence of ETI’s. The size and age of the Universe suggests that many technologically advanced ETI’s ought to exist. However, this hypothesis seems inconsistent with the lack of observational evidence to support it.i”The Fermi Paradox is the contradictory and counter-intuitive observation that we have yet to see any evidence for the existence of ETI’s. The size and age of the Universe suggests that many technologically advanced ETI’s ought to exist. However, this hypothesis seems inconsistent with the lack of observational evidence to support it.
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There are more stars in the Universe than we can possibly fathom. Any conception of ‘rare’ ‘not enough time’ or ‘far away’ has to be set against the inability of human psychology to grasp such vast cosmological scales and quantities. The Universe and the Milky Way are extremely old, our galaxy has been able to produce rocky planets for quite some time now, and our earth is a relative new-comer to the galaxy.
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The fact that our Galaxy appears unperturbed is hard to explain. We should be living in a Galaxy that is saturated with intelligence and highly organized. Thus, it may be assumed that intelligent life is rare, or, given our seemingly biophilic Universe, our assumptions about the general behaviour of intelligent civilizations are flawed.

A paradox is a paradox for a reason: it means there’s something wrong in our thinking.

I agree. I am going with the it is hard for life to start and it what has started is really far away (so we can’t detect what life there is). Another option I could believe is once you reach a certain level of technological sophistication you often wipe out your civilization – leaving relatively short periods where civilizations produce signals we can detect (included in this is creating something that wipes themselves out, and a nasty thing [virus, bacteria, whatever…] that spreads everywhere because of instant transportation and wipes everybody out). Or maybe civilizations quickly go through a technology phase producing signals we can detect and move onto something else (though I can’t really understand why or what that would mean really). Or, similar to that one, for some reason we are really really odd in our move to technology – maybe most of the time things just stay in a natural state and nothing evolves that wants to do more than eat and sleep (if they sleep). That seems really unlikely but…

Contradictory Medical Studies

I have written before about false research findings. This is an important topic – we need to remember that the interpritation of one study (or many studies) in not necessarily conclusive. Another article – When Medical Studies Collide:

Two years ago, the headlines blared that echinacea was a bust. Millions of people who believed the best-selling herbal remedy was warding off colds were probably deluding themselves, according to The New England Journal of Medicine. Now echinacea is back in the news. This time, it works! So says a study in The Lancet Infectious Diseases.

How could two studies come to such different conclusions—especially when there have been no new trials of the herb? While the New England Journal reported on one clinical trial, authors of the latest report combined data from previous studies, a controversial approach called a meta-analysis. Its conclusion is dramatically different—not just from that of the New England Journal paper, but also from a review last year of the same studies.
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The problem is, the world of medical and health research is messier than most people realize. Black-and-white answers are rare, even when it comes to a single drug trial.

Just remember those last two sentences. Very simple. And most people would agree if you showed them those two sentences and asked if they agreed. But then they see a headline and away they go… Just force yourself to repeat that idea every time you see a health report. Don’t believe the headline without strong support.

An interesting tidbit from the article. The coneflower is the source of echinacea. I tried to find photos that I am pretty sure I have on my hard drive of the flowers in my back yard, but I couldn’t.

Related: Correlation is Not Causation – Another Paper Questions Scientific Paper Accuracy