Sunday, May 30, 2010

From butterflies' wings to bank notes - how nature's colors could cut bank fraud

Scientists have discovered a way of mimicking the stunningly bright and beautiful colours found on the wings of tropical butterflies. The findings could have important applications in the security printing industry, helping to make bank notes and credit cards harder to forge.

The bright green wings of the P. blumei butterfly result from the mixing of the different colors of light that are reflected from different regions of the scales found on the wings of these butterflies
IMAGE: The bright green wings of the P. blumei butterfly result from the mixing of the different colors of light that are reflected from different regions of the scales found on the wings of these butterflies.

Credit: Mathias Kolle, University of Cambridge







The striking iridescent colours displayed on beetles, butterflies and other insects have long fascinated both physicists and biologists, but mimicking nature's most colourful, eye-catching surfaces has proved elusive.

This is partly because rather than relying on pigments, these colours are produced by light bouncing off microscopic structures on the insects' wings.

Mathias Kolle, working with Professor Ullrich Steiner and Professor Jeremy Baumberg of the University of Cambridge, studied the Indonesian Peacock or Swallowtail butterfly (Papilio blumei), whose wing scales are composed of intricate, microscopic structures that resemble the inside of an egg carton.


This SEM image of concavities is covered by a conformal multilayer stack of 11 alternating layers of titania and alumina.
IMAGE: This SEM image of concavities is covered by a conformal multilayer stack of 11 alternating layers of titania and alumina.

Credit: Mathias Kolle, University of Cambridge

Because of their shape and the fact that they are made up of alternate layers of cuticle and air, these structures produce intense colours.

Using a combination of nanofabrication procedures – including self-assembly and atomic layer deposition – Kolle and his colleagues made structurally identical copies of the butterfly scales, and these copies produced the same vivid colours as the butterflies' wings.

According to Kolle: "We have unlocked one of nature's secrets and combined this knowledge with state-of-the-art nanofabrication to mimic the intricate optical designs found in nature."

"Although nature is better at self-assembly than we are, we have the advantage that we can use a wider variety of artificial, custom-made materials to optimise our optical structures."

As well as helping scientists gain a deeper understanding of the physics behind these butterflies' colours, being able to mimic them has promising applications in security printing.

"These artificial structures could be used to encrypt information in optical signatures on banknotes or other valuable items to protect them against forgery. We still need to refine our system but in future we could see structures based on butterflies wings shining from a £10 note or even our passports," he says.

Intriguingly, the butterfly may also be using its colours to encrypt itself – appearing one colour to potential mates but another colour to predators.

This scanning electron micrograph shows that the surface of a wing scale is covered with concavities

IMAGE: This scanning electron micrograph shows that the surface of a wing scale is covered with concavities.

Credit: Mathias Kolle, University of Cambridge

Kolle explains: "The shiny green patches on this tropical butterfly's wing scales are a stunning example of nature's ingenuity in optical design. Seen with the right optical equipment these patches appear bright blue, but with the naked eye they appear green.

"This could explain why the butterfly has evolved this way of producing colour. If its eyes see fellow butterflies as bright blue, while predators only see green patches in a green tropical environment, then it can hide from predators at the same time as remaining visible to members of its own species."

The results are published today in Nature Nanotechnology.


Monday, May 24, 2010

Fitness First Weight Splashing Billboard At Bus Stop

Fitness First Weight Splashing Billboard At Bus Stop

Terrifying or brilliant marketing idea, it is up you to decide?

Global fitness chain Fitness First has come up with new marketing idea by constructing a bus stop with weight splashing billboard in Netherlands.

If any commuter sit at the bus stop, the commuter weight will be shown at the billboard.

It's a noble effort taken by Fitness First to promote the important of taking care one health by doing exercise.

However, if my weight is more than 100 kg, certainly I don't want to take a seat at the bus stop.



Saturday, May 22, 2010

Process Involved In Drilling A Relief Well in the Gulf of Mexico

BP crews are set to begin drilling a relief well in the Gulf of Mexico (GoM) to stem the flow from the MC252 well.

A drilling rig drills a relief well or second well to intersect the original, flowing well as deeply as possible. A specialized heavy liquid is then pumped into the flowing well to bring it under control.

This liquid is denser than oil and so exerts pressure (known as hydrostatic pressure) to stem the flow of oil. Once the flow is stopped, the well can be returned to a safe condition.

A relief well should be faster to drill than the original well thanks to the knowledge already gained about the geology and pressure in the reservoir.

However, drilling a well of this nature presents many technical challenges to ensure that the flowing well is intersected in the right position and that the fluid pumping operations are effective.

BP has assembled a world-class team of experts from within the company and key specialists in the industry to ensure that the relief well operations are conducted safely and successfully.

A second relief well could form part of the contingency plans in case the first well encounters any delays. This means that progress can still be made to stem a flowing well should one drilling operation encounter a problem.

BP Relief Well Diagram



Monday, May 17, 2010

Prehistoric fish extinction paved the way for modern vertebrates

Event of unknown origin occurred as first vertebrates tested land

A mass extinction of fish 360 million years ago hit the reset button on Earth's life, setting the stage for modern vertebrate biodiversity. The mass extinction scrambled the species pool near the time at which the first vertebrates crawled from water towards land.

Those few species that survived the bottleneck were the evolutionary starting point for all vertebrates--including humans--that exist today, according to results of a study published this week in the journal Proceedings of the National Academy of Sciences (PNAS).

"Everything was hit; the extinction was global," said Lauren Sallan of the University of Chicago and lead author of the paper. "It reset vertebrate diversity in every single environment, both freshwater and marine, and created a completely different world."

The Devonian Period, which spanned from 416 to 359 million years ago, is also known as the Age of Fishes for the broad array of species present in Earth's aquatic environments.

Armored placoderms such as the gigantic Dunkleosteus and lobe-finned fishes--similar to the modern lungfish--dominated the waters, while ray-finned fishes, sharks and tetrapods were in the minority, according to Maureen Kearney, program director in the National Science Foundation (NSF)'s Division of Environmental Biology, which funded the research, along with NSF's Division of Earth Sciences.

But between the latest Devonian Period and the subsequent Carboniferous period, placoderms disappeared and ray-finned fishes rapidly replaced lobe-finned fishes as the dominant group, a demographic shift that persists to today.

"The Devonian period is known as the Age of Fishes, but it's the wrong kind of fish," Sallan said. "Just about everything dominant in the Devonian died at the end of the period and was replaced."

"There's some sort of pinch at the end of the Devonian," said the paper's second author, Michael Coates, an organismal biologist and anatomist at the University of Chicago.

"It's as if the roles persist, but the players change: the cast is transformed dramatically. Something happened that almost wiped the slate clean, and, of the few stragglers that made it through, a handful then re-radiate spectacularly."

Scientists have long theorized that the Late Devonian Kellwasser event--considered to be one of the "Big Five" extinctions in Earth's history--was responsible for a marine invertebrate species shake-up.

But an analysis of the vertebrate fossil record by Sallan and Coates pinpointed a critical shift in diversity to the Hangenberg extinction event 15 million years later.

Prior to the extinction, lobe-finned forms such as Tiktaalik and the earliest limbed tetrapods such as Ichthyostega had made the first tentative "steps" toward a land-dwelling existence.

But after the extinction, a long stretch of the fossil record known as "Romer's Gap," is almost barren of tetrapods, a puzzle that had confused paleontologists for many years.

Sallan and Coates' data suggest that the 15-million-year gap was the hangover after the traumatic Hangenberg event.

"Something that's seen after an extinction event is a gap in the records of survivors," Sallan said. "You have a very low diversity fauna, because most things have been killed off."

When tetrapods finally recovered, those survivors were likely the great-great-grandfathers to the vast majority of land vertebrates present today.

Modern vertebrate traits--such as the motif of five-digit limbs that is shared by all mammals, birds and reptiles in utero--may have been set by this early common ancestor, the authors propose.

"Extinction events remove a huge amount of biodiversity," Coates said. "That shapes in a very significant way the patchiness of biodiversity that persists to the present day."

The analysis benefitted from recent advances in filling in the vertebrate fossil record, Coates said.

Previously, estimates of the earlier extinction had been made using fossils of invertebrates such as mollusks and clams, which are far more abundant.

With a larger dataset of vertebrates and analytical techniques borrowed from modern ecology, Sallan and Coates were able to see the abrupt changes in species composition before and after the Hangenberg event.

"It's a big extinction during what was already considered a critical time in vertebrate evolution, so it's surprising that it went unnoticed for so long," Sallan said. "But it took the right methods to reveal its magnitude."

What remains mysterious is exactly what happened 360 million years ago to trigger this mass extinction.

Other researchers have found evidence of substantial glacier formation at the end of the Devonian period, which would have dramatically lowered sea levels and affected life.

The first appearance of forest-like environments in some regions might also have produced atmospheric changes catastrophic to animal life.

The research also raises questions about the pattern of evolution after the extinction event.

It remains unclear why groups that were abundant before the event did not recover, while other groups spread and diversified in radical new ways.

Regardless of these questions, the consequences are still being felt hundreds of millions of years later.

"It is a pivotal episode that shaped modern vertebrate biodiversity," Coates said. "We are only now beginning to place that important event in the history of life and the history of the planet, which we weren't able to do before."

###
Funding was also provided by the University of Chicago Hinds Fund, the Paleontological Society, the Palaeontological Association, the American Society of Ichthyologists and Herpetologists, and the Evolving Earth Foundation.


The flora and fauna of the Devonian and Carboniferous periods

Tuesday, May 4, 2010

24K Gold-Plated USB Drive From Gold Noble


A Korean company called Gold Noble has just launch a 24 K Gold-plated usb drive.
It has 8 GB data storage and if you want to buy one, expect to spend about 106 USD for the usb drive. It is design just like a gold bar.
To order the 24k gold plated usb drive, please visit Gold Noble's site below.
You can buy the usb drive as a gift for your loved ones.


24K Gold-Plated USB Drive From Gold Noble
24K Gold-Plated USB Drive From Gold Noble






24K Gold-Plated USB Drive From Gold Noble


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