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Archive for the ‘Nature’ Category

US Military Air Drones May Get Insect Hair Coats

October 3, 2011 Leave a comment

“For years, the military has turned to the birds and the bees for inspiration, churning out mechanical hummingbirds and remote-controlled insect cyborgs.

Now the Pentagon wants its mini-drones to have hairy wings and bug eyes, too. It’ll help the tiny machines spy on — and creep out — any enemies, military researchers promise…

Nature will be the engineers’ muse. A project to equip MAVs with hair-like sensors hopes to produce “the flight efficiency and agility of the hawkmoth,” the insect known for its hovering flight patterns.

To figure out how MAVs could keep flying smoothly even when the wind pipes up, another group is looking at how hair cells on bees’ bodies sense changes in air flow.”

Reusable Glass Nanoparticle Sponge Can Extract Toxins From Water

October 3, 2011 Leave a comment

A flexible web of glass nanoparticles makes up each piece of Osorb. When it comes in contact with pollutants, the web opens up to encapsulate them, causing the Osorb to swell. Ben Goldstein

“Chemist Paul Edmiston has plenty of data to prove how well Osorb, a glass substance, soaks up petroleum, solvents and other organic contaminants.

But he’s most convincing when he mixes motor oil with water, adds Osorb, filters off the swollen powder and drinks the remaining liquid. “It works like a nanomechanical sponge,” he says. “I’ve done trace analysis, and the water’s totally clean.”

A graduate student of Edmiston’s stumbled upon the material while experimenting with molecules for a bomb-detection device. After she added acetone to a beaker of silicas, they ballooned to eight times their normal size. She went straight to Edmiston, asking, “Did I mess up?”

Much to the contrary: The silicas, Edmiston realized, are hydrophobic, so they ignore water but grab both polar compounds (such as acetone) and nonpolar ones (such as octane) out of solution.

The contaminants can be released for disposal or recycling by squeezing the nanomechanical sponge—that is, by applying heat. The swellable glass can be reused more than 100 times.”

A Cosmic Thermostat Controls Earth’s Temperature?

October 1, 2011 Leave a comment

“In recent years, the idea that the climate is driven by clouds and cosmic rays has received plenty of attention. Interest in the idea was prompted by a Danish physicist named Henrik Svensmark, who first suggested it in the late 1990s.

Using satellite data on cloud coverage, which became available with the establishment of the International Satellite Cloud Climatology Project in 1983, Svensmark found a correlation between lower troposphere cloud cover and the 11-year solar cycle.

He proposed that cosmic rays initiate the formation of aerosols in the lower atmosphere that then form condensation nuclei for cloud droplets, increasing cloud formation from water vapor. Since low-level clouds increase Earth’s albedo (the amount of incoming solar radiation that is reflected back into space), more clouds mean cooler temperatures.

Svensmark claimed that this mechanism was responsible for virtually every climatic event in Earth history, from ice ages to the Faint Young Sun paradox to Snowball Earth to our current warming trend. Needless to say, this would overturn decades of climate research.

Cosmic “rays” are actually energetic subatomic particles. The solar wind shields the Earth from many of the cosmic rays coming from elsewhere in the Milky Way, so the number of rays that reach the Earth is modulated by variations in solar activity, such as the well-known 11-year solar cycle.

Early work by Svensmark and a group at CERN (we recently covered their initial results) has indicated that charged particles like cosmic rays can cause molecules of sulfuric acid, water, or other vapors to combine and form aerosols (particles about 1 nanometer in diameter). This provides a potential link between cosmic rays and cloud formation.”

Chlorophyll’s Competitor Arrives: Artificial Leaf Created

October 1, 2011 1 comment

“Researchers led by MIT professor Daniel Nocera have produced something they’re calling an “artificial leaf”: Like living leaves, the device can turn the energy of sunlight directly into a chemical fuel that can be stored and used later as an energy source.

The artificial leaf — a silicon solar cell with different catalytic materials bonded onto its two sides — needs no external wires or control circuits to operate.

Simply placed in a container of water and exposed to sunlight, it quickly begins to generate streams of bubbles: oxygen bubbles from one side and hydrogen bubbles from the other.

If placed in a container that has a barrier to separate the two sides, the two streams of bubbles can be collected and stored, and used later to deliver power: for example, by feeding them into a fuel cell that combines them once again into water while delivering an electric current.”

Messenger Takes Shocking “Cheesy” Photos of Mercury

September 30, 2011 Leave a comment

“The planet Mercury is dotted with holes that appear to be unlike any other landform yet seen in the solar system, new pictures show.

High-resolution photographs from NASA’s MESSENGER spacecraft revealed the shallow, rimless, irregularly shaped depressions—similar to the holes in Swiss cheese—in impact craters all over Mercury.

The features are “widespread both in latitude and longitude,” said study co-author David Blewett, of the Johns Hopkins University Applied Physics Laboratory in Maryland.

Dubbed hollows, the odd landforms can be tens of meters to a few kilometers wide, whereas the impact craters that contain them are tens of kilometers wide or bigger.

The hollows are often seen in clusters on the walls, floors, and peaks of the craters. Many hollows have smooth, flat bottoms and feature highly reflective material.

While Mercury had previously been thought of as a geologically dead planet, with few changes to its surface over the past billion years, “these [hollows] just look fresh,” Blewett added.

“I think there’s a distinct possibility that they’re active today.””

Why Do You See Stars When Hit On Your Head Or Face?

September 30, 2011 Leave a comment

“Naturally, it starts with your brain.

A little set up: The part of the brain that handles what you see is called the occipital lobe,; it’s located at the back of your head. Its job is to take the information sent from the retina and turn it into something that makes sense to you.

So before you know that the thing in front of you is actually your cat chewing on a power cord, your retina has to take the observable light, convert it first into a chemical signal, and then into an electrical impulse, before sending back to you brain for interpretation.

The occipital lobe will then say, yup, based on this information, that’s your cat trying to off himself. You get the idea: Your eyes and your brain work together to understand what’s in front of you.

Your brain reads other types of stimulation, too. Robert Wade Crow, an assistant clinical professor of neuro-ophthalmology at UC Irvine explains, “If you irritate the brain, it may create a response like it’s normally used to creating, which is, in this case, a visual response.”

Poking the occipital lobe can make it cry vision. The thing is, the response is not anchored to anything, so instead of seeing floating suicidal cats or baseballs speckling your vision when the occipital lobe is bumped, you just see light.”

Can A Chicken Be “Reverse-Evolved” Into A Dinosaur?

September 27, 2011 Leave a comment

“Renowned paleontologist Jack Horner has spent his career trying to reconstruct a dinosaur.

He’s found fossils with extraordinarily well-preserved blood vessels and soft tissues, but never intact DNA.

So, in a new approach, he’s taking living descendants of the dinosaur (chickens) and genetically engineering them to reactivate ancestral traits — including teeth, tails, and even hands — to make a “Chickenosaurus”.”