Tag Archives: Science

President Obama Speaks on Getting Students Excited About Science and Engineering

The President announces the “Educate to Innovate” initiative, a campaign to get students excited about pursuing careers in science, technology, engineering and mathematics. Quotes from President Obama from his speech – (see webcast above):

“As President, I believe that robotics can inspire young people to pursue science and engineering.”

“Now the hard truth is that for decades we’ve been losing ground. One assessment shows American 15-year-olds now rank 21st in science and 25th in math when compared to their peers around the world.”

“And today, I’m announcing that we’re going to have an annual science fair at the White House with the winners of national competitions in science and technology. If you win the NCAA championship, you come to the White House. Well, if you’re a young person and you’ve produced the best experiment or design, the best hardware or software, you ought to be recognized for that achievement, too. Scientists and engineers ought to stand side by side with athletes and entertainers as role models, and here at the White House we’re going to lead by example. We’re going to show young people how cool science can be.”

“improving education in math and science is about producing engineers and researchers and scientists and innovators who are going to help transform our economy and our lives for the better.”

Re-engineering the Food System for Better Health

Good food nation

According to the Centers for Disease Control, between 1980 and 2006 the percentage of obese teenagers in the United States grew from 5 to 18, while the percentage of pre-teens suffering from obesity increased from 7 to 17.
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Obesity is widespread due to our national-scale system of food production and distribution, which surrounds children – especially lower-income children – with high-calorie products…
90 percent of American food is processed – according to the United States Department of Agriculture – meaning it has been mixed with ingredients, often acting as preservatives, that can make food fattening.
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Now, in another report finished this October after meetings with food-industry leaders, the MIT and Columbia researchers propose a solution: America should increase its regional food consumption.
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Only 1 to 2 percent of all food consumed in the United States today is locally produced. But the MIT and Columbia team, which includes urban planners and architects, believes widespread adoption of some modest projects could change that, by increasing regional food production and distribution.

To help production, the group advocates widespread adoption of small-scale innovations such as “lawn to farm” conversions in urban and suburban areas, and the “10 x 10 project,” an effort to develop vegetable plots in schools and community centers. Lawns require more equipment, labor and fuel than industrial farming nationwide, yet produce no goods. But many vegetables, including lettuce, cucumbers and peppers, can be grown efficiently in small plots.
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As Albright sees it, the effort to produce healthier foods “fits right in with the health-care reform effort right now because chronic diseases are so costly for the nation.” America currently spends $14 billion annually treating childhood obesity, and $147 billion treating all forms of obesity.

Good stuff. We need to improve health in the USA. The current system is unhealthy and needs to be improved. The public good from improving the health of society is huge (both in terms of individual happiness and economic benefits).

Web Gadget to View Cell Sizes to Scale

Image of cell size gadget from University of Utah

The Genetic Science Learning Center, University of Utah has a nice web gadget that lets you zoom in on various cells to see how large they are compared to each other. Above see a red blood cell, x chromosome, baker’s yeast and (small) e-coli bacterium.

A red blood cell is 8 micron (micro-meter 1/1,000,000 of a meter). E coli is 1.8 microns. Influenza virus is 130 nanometers (1/1,000,000,000 a billionth of a meter). Hemoglobin is 6.5 nanometers. A water molecule is 275 picometers (1 trillionth of a meter).

Science Explained: RNA Interference

Explained: RNA interference

Every high school biology student learns the basics of how genes are expressed: DNA, the cell’s master information keeper, is copied into messenger RNA, which carries protein-building instructions to the ribosome, the part of the cell where proteins are assembled.

But it turns out the picture is far more complicated than that. In recent years, biologists have discovered a myriad of other molecules that fine-tune this process, including several types of RNA (ribonucleic acid). Through a naturally occurring phenomenon known as RNA interference, short strands of RNA can selectively intercept and destroy messenger RNA before it delivers its instructions.
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Double-stranded RNA molecules called siRNA (short interfering RNA) bind to complementary messenger RNA, then enlist the help of proteins, the RNA-induced silencing complex. Those proteins cleave the chemical bonds holding messenger RNA together and prevent it from delivering its protein-building instructions.

This article from MIT is one, of many, showing MIT’s commitment to science education of the public. Good job, MIT.

Open Science: Looking at Dust

Open access paper: Migration of Contaminated Soil and Airborne Particulates to Indoor Dust.

Indoor dust is a mixture of soil tracked into a residence, particulate matter derived from ambient outdoor air, and importantly, organic matter. Indoor dust is about 40% organic matter by weight in residential housing. Particles tracked into a residence are redistributed on floor surfaces account for over 60% of the dust mass on floors.

The Only Known Cancerless Animal

Unlike any other mammal, naked mole rate communities consist of queens and workers more reminiscent of bees than rodents. Naked mole rats can live up to 30 years, which is exceptionally long for a small rodent. Despite large numbers of naked mole-rats under observation, there has never been a single recorded case of a mole rat contracting cancer, says Gorbunova. Adding to their mystery is the fact that mole rats appear to age very little until the very end of their lives.

The mole rat’s cells express p16, a gene that makes the cells “claustrophobic,” stopping the cells’ proliferation when too many of them crowd together, cutting off runaway growth before it can start. The effect of p16 is so pronounced that when researchers mutated the cells to induce a tumor, the cells’ growth barely changed, whereas regular mouse cells became fully cancerous.

“It’s very early to speculate about the implications, but if the effect of p16 can be simulated in humans we might have a way to halt cancer before it starts.” says Vera Gorbunova, associate professor of biology at the University of Rochester and lead investigator on the discovery.

In 2006, Gorbunova discovered that telomerase—an enzyme that can lengthen the lives of cells, but can also increase the rate of cancer—is highly active in small rodents, but not in large ones.

Until Gorbunova and Seluanov’s research, the prevailing wisdom had assumed that an animal that lived as long as we humans do needed to suppress telomerase activity to guard against cancer. Telomerase helps cells reproduce, and cancer is essentially runaway cellular reproduction, so an animal living for 70 years has a lot of chances for its cells to mutate into cancer, says Gorbunova. A mouse’s life expectancy is shortened by other factors in nature, such as predation, so it was thought the mouse could afford the slim cancer risk to benefit from telomerase’s ability to speed healing.

While the findings were a surprise, they revealed another question: What about small animals like the common grey squirrel that live for 24 years or more? With telomerase fully active over such a long period, why isn’t cancer rampant in these creatures?

Undergraduate Student Discovers Herbivorous Spider

Herbivory Discovered in a Spider

A jumping spider from Central America eats mostly plants, according to new research. Spiders were thought to be strictly predators on animals. The spider, Bagheera kiplingi, was described scientifically in the late 1800s, but its vegetarian tendencies were not observed until the 21st century.

“This is the first spider in the world known to deliberately hunt plant parts. It is also the first found to go after plants as a primary food source,” said lead author Christopher Meehan.
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Of the approximately 40,000 species of spiders known, Bagheera kiplingi is the only species known to be primarily herbivorous. Ironically, the vegetarian spider is named after the panther in Rudyard Kipling’s “The Jungle Book.” The spider inhabits several species of acacia shrubs involved in a well-known mutualism between the acacias and several species of ants.
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Previously, very few spiders had been seen consuming plants at all. Some spiders had been observed occasionally eating nectar and pollen, although the bulk of their diet was insects and other small animals.

Dennis Bray Podcast on Microbes As Computers

Carl Zimmer interviews Dennis Bray in an interesting podcast:

Dennis Bray is an active professor emeritus in both the Department of Physiology and Department of Neuroscience at the University of Cambridge. He studies the behavior of microbes–how they “decide” where to swim, when to divide, and how best to manage the millions of chemical reactions taking place inside their membranes. For Bray, microbes are tiny, living computers, with genes and proteins serving the roles of microprocessors.

William Kamkwamba on the Daily Show

Pointy haired bosses removed the video. Argh!

William Kamkwamba on the Daily show. I first posted about William’s great work in 2007 – Home Engineering: Windmill for Electricity. What a great example of what can be done by sharing scientific and engineering ideas with those who will make the effort to create workable solutions.

William has written a book on his life: The Boy Who Harnessed the Wind.

The Nobel Prize in Physics 2009

The 2009 Nobel Prize in Physics honors three scientists, who have had important roles in shaping modern information technology, with one half to Charles Kuen Kao and with Willard Sterling Boyle and George Elwood Smith sharing the other half. Kao’s discoveries have paved the way for optical fiber technology, which today is used for almost all telephony and data communication. Boyle and Smith have invented a digital image sensor – CCD, or charge-coupled device – which today has become an electronic eye in almost all areas of photography. The Nobel prize site includes great information on the science behind the research that has been honored:

The first ideas of applications of light guiding in glass fibers (i.e. small glass rods) date from the late 1920’s. They were all about image transmission through a bundle of fibers. The motivation was medicine (gastroscope), defense (flexible periscope, image scrambler) and even early television. Bare glass fibers were, however, quite leaky and did not transmit much light. Each time the fibers were touching each other, or when the surface of the fibers was scratched, light was led away from the fibers. A breakthrough happened in the beginning of the 1950’s with the idea and demonstration that cladding the fibers would help light transmission, by facilitating total internal reflection.
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Optical communication of today has reached its present status thanks to a number of breakthroughs. Light emitting diodes (LEDs) and especially diode lasers, first based on GaAs (800-900 nm) and later on InGaAsP (1-1.7 ïm), have been essential. The optical communication window has evolved from 870 nm to 1.3 ïm and, finally, to 1.55 ïm where fiber losses are lowest. Gradient-index fibers were used in the first optical communication lines. However, when moving towards longer wavelengths and longer communication distances, single-mode fibers have become more advantageous.

Nowadays, long-distance optical communication uses single mode fibers almost exclusively, following Kao’s vision. The first such systems used frequent electronic repeaters to compensate for the remaining losses. Most of these repeaters have now been replaced by optical amplifiers, in particular erbium-doped fiber amplifiers. Optical communication uses wavelength division multiplexing with different wavelengths to carry different signals in the same fiber, thus multiplying the transmission rate. The first non-experimental optical fiber links were installed in 1975 in UK, and soon after in the US and in Japan. The first transatlantic fiber-optic cable was installed in 1988.