CAN 3D printing shape the global economy

By | November 14, 2012, 8:00 AM PST


Lately, it seems like nearly everything has been reproduced by a 3D printer. Between the group that 3D printed a gun, the people who printed a drone, and the army of items sold at this small marketplace for 3D printed goods, there are plenty of novelty uses for these suddenly trendy machines. We’re a long way from 3D printing a house, but it’s clear that the hobby is inching into the mainstream.
Yet it’s difficult not to wonder: at what point will 3D printing move beyond novelty to industry? Will these machines change the way we manufacture goods, and subsequently change the global economy, too? (Is it already happening before our very eyes?)
The answer: yes and no. The term “3D printing” comprises two very different worlds: hobbyist 3D printing, where people with relatively inexpensive machines print plastic objects in the comfort of their homes; and industrial 3D printing, which is usually referred to by another name: additive manufacturing. They are vastly different and will likely have divergent impacts on the economy. Both, however, are poised to alter the way businesses think about production.
Homeward bound
Right now, home 3D printing is relatively exclusive to hobbyists and makers. A machine for the purpose costs about $4,000, and typically only prints objects from plastic. For now, those objects tend to verge on the trivial: bracelets, puzzle games, figurines. But some envision a future where people will be able to 3D print replacement parts, or even entire products, at home.
The arc of the 3D printing trend is similar to other technologies, says Cherie Ann Sherman, an economist at Ramapo College in New Jersey. In its infancy, the technology is today confined to crafts, hobbyists and hackers. But the path is well-worn. “If you think back to computers, that’s how personal computers started,” Sherman said. “They were being sold in hobby stores.”
In the modern age of mass manufacturing, consumers aren’t fixers. Most people don’t take their toaster apart to figure out what’s wrong with it, and even fewer will want to then 3D print a replacement part. But 3D printing can still have a huge impact on the home product economy, says Phil Anderson, an inventor and Ramapo College professor. Rather than each person having their own printer at home, local businesses and hardware stores could adopt the technology. Take your faulty toaster to Home Depot or Sears, and a store employee could isolate the problem and print your solution on the spot.
The development path of 3D printing could resemble that of photo printing, Anderson says. When it became affordable for people to have printers in their homes, people began printing their own photos. Today, most people don’t print their own photos, despite increasingly better home technology; instead, they avoid printing at all, and reserve the special occasions that they do for shops with high quality print services. The same could hold for 3D printing: if printers become affordable enough, many people might initially buy them, but they will eventually turn to specialized shops to get the job done as the technology becomes ubiquitous.
Still, the economic impact of these kinds of 3D printed products — one-off components or replacement parts — could be radical, Anderson says. They could eliminate the need for huge warehouses of parts and cut the need for shipping different components from place to place as they’re ordered, in favor of instantly creating a perfect replica on-site. Three-dimensional printing could reduce or eliminate some of the steps between product creators and consumers. The existence of the middle man that buys, sells and ships is threatened.
I can cost-effectively make a cell phone cover that is unique to every customer,” explains Ryan Wicker, a researcher at the University of Texas at El Paso. “I could build 100 different ones just as cost-effectively as building them all the same.” That flexibility and direct delivery is why 3D printing might change the markets for home appliances, jewelry and other small goods.
Sherman likens it to the way the Internet has cut the middle man from artists who can now promote their art or music online without a big record label attached to them. Now, people discover musicians on YouTube as easily as the radio. “You can be the Carly Rae Jepson of 3D printing,” she laughs.
The factory floor
Far from your living room or office is the world of the factory — the large, the numerous, at a scale that eclipses that of a human. This world of 3D printing, or, as industry designers call it, “additive manufacturing,” is far more mature. Industry has been printing parts for years now, from plastic vents to airplane parts to cars.
Take U.S. aerospace leader Boeing, for example. The company has two entire divisions dedicated to additive manufacturing: one for plastics, and another for metals. The two present quite different challenges. Plastic 3D printing is a more developed process, used for simple components such as vents and knobs. Metals, on the other hard, are far more complex, often used for structural components that require more safety oversight. Yet parts comprised of either material are made with the same process. More applications are expected in the near future.
As adoption increases, the potential impact of additive manufacturing on the labor force is difficult to understate. Traditional manufacturing requires a lot of unskilled labor, which is far less expensive in developing nations such as China and India. As globalization took hold over the last several decades, international outsourcing by companies pulled jobs away from former manufacturing hubs like the United States. In an additive manufacturing-based industry, that’s not necessary. Plus, the jobs that support it tend to be more, not less, skilled.You’re electromagnetically steering an electron beam, which is a very powerful energy source,” says Dave Dietrich, the lead engineer from the metals group at Boeing. “These people are heavily trained technicians.”
Three-dimensional printing also stands to make industrial design more efficient; with new capabilities comes new processes. Take a complicated engine piece, for example: what once required several pieces manufactured separately then fit together can now be designed and printed as one piece. For the airline industry, for example, that means lighter parts that translate to reduced fuel costs. “Even though we live in a 3D world, most of our products are designed in 2D,” Wicker says. “Just imagine allowing the full creativity of my designer to take advantage of all three dimensions.”
For big industry, a better bottom line makes additive manufacturing worth it, allowing for efficiencies in the process, speed and cost of manufacturing. For now, the costs to research and begin implementing such a process are large. But the future is clear, says Michael Hayes, the lead engineer for Boeing’s non-metal based 3D printing team. Five years from now, designing in three dimensions will mean that each part will be designed to perform several functions, rather than just one, he says.
Whether for leisure or line production, the predicted effects of the 3D printing process are manifold and immense. All it takes is a few big companies to sign on to set in motion a major shift in global markets, Sherman says. “These companies don’t see the technology as ripe yet,” he said. “Once they take a step in that direction, that’s when it will really have its impact.”
Image: Keith Kissel



Finally, an article that at least cautions readers not expect that the world is going to be changed by 3-D printing - at least drastically. What is it about the material and cost limitations - the economics of "3-D" printing that is so hard for reporters to understand. Don't you get comparing 3-D printing to the internet - is totally inappropriate and just logically lame. The idea that Home Depot is going to start repair shops using 3-D printers for parts is economically absurd. The idea that I'm going to go to a 3-D printing booth to make a new handle for the screw driver I broke yesterday is equally absurd, because the price of the 3-D printing material (assuming it is structurally adequate) is more than the cost of the a new screw driver. It's the economics - or the lack thereof that has and still governs the applications of 3-D printing - not the technology.

Why not just state the obvious -there are certain types of tasks - such as single material small number component product development where 3-D printing can excel, however these are relatively limited number of applications. At the same time 3-D P will be economically unfeasible for many other production processes where existing tech like die cast molding large numbers of products where 3-D printed products can't come close to competing - ever. It's just simple math. physics and basic economics.
Posted by dduggerbiocepts
2 days ago
0 Votes
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3D Printing Problems
There are two problems with 3D printing that will impact this.

First, is the issue of time. 3D printing is SLOW. Compare injection molding with 3D printing. In the time that the 3D printer can make a single part, the injection molding machine will make a couple of dozed, or even a couple of hundred. Time is a big cost. That's the whole reason for Mass Production.

Second is the issue of materials. because of the time factor above, any single 3D printer will not use a terribly large amount of material. Because of the larger throughput, the injection molding machine will use much more, so the amount purchased will be much larger, driving the cost per Kg down.

Adding these two factors together, relegates the 3D printer to a niche area of manufacturing.

Still, there is a place where 3D printing shines. That is in prototyping situations, and where there is only a very limited product run needed. Those are the areas where a 3D printer will really make an impact.

I wouldn't want to rely on a 3D printer if my business is selling screws or screwdrivers, but, it would be really valuable on say a spaceship, where a replacement part is vital, and we are weeks away from any factory. It would also be quite useful for a car buff that needs a part that hasn't been made for 40 years.

In industry, it is already very useful for making the parts that are then used to make the molds for mass production. 3D printing will never make everything we as a planetary economy want and need. It will, however be added as another valuable tool. Every new tool adds some value.
Posted by YetAnotherBob
Updated - 1 day ago
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Acupuncture  help patients with depression


WASHINGTON: A new study suggests that acupuncture or counselling, provided alongside usual care, could benefit patients with depression.


The study, conducted by a team led by Dr Hugh MacPherson, of the department of health sciences at the University of York, found that in a primary care setting, combining acupuncture or counselling with usual care had some benefits after three months for patients with recurring depression.

The study, which also involved researchers from the Centre for Health Economics at York and Hull York Medical School, was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research Programme.

Many patients with depression are interested in receiving non-drug therapies, however, there is limited evidence to support the use of acupuncture or counselling for depression in a primary care setting. In this pragmatic randomised-controlled trial conducted in the north of England, the research team randomised patients with depression to receive 12 weekly sessions of acupuncture plus usual care (302 patients), or 12 weekly sessions of counselling plus usual care (302 patients), or usual care alone (151 patients).

Compared with usual care alone, there was a significant reduction in average depression scores at three months for both the acupuncture and counselling interventions, but there was no significant difference in depression scores between the acupuncture and counselling groups. At nine months and 12 months, because of improvements in the depression scores in the usual care group, acupuncture and counselling were no longer better than usual care.

The study is published in the journal PLOS Medicine.

densest galaxy known in the local universe,


Densest galaxy ever discovered


WASHINGTON: Astronomers have discovered the densest galaxy ever to be found - packed with an extraordinary number of stars - about 54 million light years from our own Milky Way.
The ultra-compact dwarf galaxy, dubbed M60-UCD1, was found in what's known as the Virgo cluster of galaxies, researchers said.
Imagine the distance between the Sun and the star nearest to it - Alpha Centauri. That's a distance of about 4 light years. Now, imagine as many as 10,000 of our Suns crammed into that relatively small space.
That is about the density of a galaxy discovered by an international team of astronomers led by a Michigan State University faculty member.
"This galaxy is more massive than any ultra-compact dwarfs of comparable size and is arguably the densest galaxy known in the local universe," said Jay Strader, MSU assistant professor of physics and astronomy.
The galaxy was discovered in the Virgo cluster of galaxies, a collection of galaxies located about 54 million light years from our own Milky Way.
What makes M60-UCD1, so remarkable is that about half of its mass is found within a radius of only about 80 light years. This would make the density of stars about 15,000 times greater than found in Earth's neighbourhood in the Milky Way.
"Travelling from one star to another would be a lot easier in M60-UCD1 than it is in our galaxy. Since the stars are so much closer in this galaxy, it would take just a fraction of the time," Strader said.
The discovery of ultra-compact galaxies is relatively new - only within the past 10 years or so. Until then, astronomers could see these "things" way off in the distance but assumed they were either single stars or very-distant galaxies.
Another intriguing aspect of this galaxy is the presence of a bright X-ray source in its centre. One explanation for this is a giant black hole weighing in at some 10 million times the mass of our Sun.

World’s first: A car driven by attention


MELBOURNE: Researchers claim to have developed the world's first attention-powered car — a pioneering vehicle that uses a headset to monitor brain activity and slow acceleration during periods of distraction.

The car commissioned by the The Royal Automobile Club of West Australia was tested in Perth in a bid to prevent road accidents due to inattention. The makers describe it as a "car that goes when you're paying attention, and slows when you're not."

The technology behind the vehicle uses a neuro headset that connects to brain activity linked to the car's engine via customized software, 'PerthNow' reported. The software communicates with the car and slows the vehicle when the driver's concentration lapses. The headset measures the electrical activity in a person's brain and feeds it into an algorithm that determines if the driver is paying attention or not.

genomic therapies to tackle tumor-prone years


Treatment for cancer lies in our genes


NEW DELHI: It's a warning that should be heeded. Even as experts say that the US will face a crisis in cancer care as an aging population reaches its tumor-prone years, scientists have developed revolutionary genomic therapies to tackle this looming crisis. So revolutionary, in fact, that the treatment for cancer now lies in our genes itself.

Most cancers have variations which can be decoded by their DNA. Specific tests now zero in on these DNA, leading to targeted treatment. "Previously, cancers were treated with a crude approach using multiple chemotherapy drugs with many side-effects," says Dr S V S Deo, associate professor, department of surgical oncology, All India Institute of Medical Sciences, Delhi. "Targeted therapy is like a 'smart bomb' which specifically attacks cancer cells without harming normal tissues and has minimal side effects." It is being used successfully for breast, lung, gastrointestinal and blood cancer.

The success of these biological therapies depends on identifying the defect in a cancer cell, says Dr Radheshyam, consultant, medical oncologist, HCG Cancer Centre, Bangalore. "In some tumors, precision medicine is going to be a significant part of overall treatment. While there are hundreds of chemotherapy drugs, in advanced cancers, both chemo and targeted therapy are given."

These therapies are especially beneficial for hereditary cancer and selectively kill cancer cells by interacting with the receptors. "Some targeted therapies even have the advantage that they lead to minimal hair loss," says Dr Sunil Kumar Gupta, senior consultant, Rajiv Gandhi Cancer Institute and Research Centre, Delhi.

For these biological therapies, first tissue is taken from the tumour and a DNA test done. This will show up genetic abnormalities and mutations. Sometimes a drug that works on a mutated lung cancer cell can also work for some other cancer. So scientists have to find which treatment works for which mutation in which organ.

There are different DNA tests for different cancers depending on their mutations. For example, BRCA testing helps in identifying women at risk for developing breast cancer with a family history. "Gene profiling tests like Oncotype Dx and mamma print help in knowing the risk of cancer recurring and the treatment can be tailored to the patient's needs. They also provide information on the need for chemotherapy," says Deo. Oncotype Dx is, however, done by labs in the US.

Oncotype Dx, says Gupta, analyzes 21 genes in a tumor to determine whether the patient should be given only hormonal therapy (for low risk patients) or chemotherapy (high risk). For lung cancer, EGFR, AIK and Her-2 gene tests are done and for colorectal cancer, K-ras gene mutation analysis.

These revolutionary treatments are a mind-boggling field and expensive with the costs varying between Rs 3 lakh to Rs 10 lakh, says Deo. While some 25% of cancer patients at AIIMS receive some form of targeted therapy, at HCG hospital more than 100 patients have been treated with this procedure. And at Rajiv Gandhi Cancer Institute, plans are afoot to start a Hereditary Genetic Cancer Clinic.

Safety devices for personal protection


AMRITAPURI (Kerala): Help is at hand for the vulnerable, especially women, the elderly and children, say scientists Krishnashree Achuthan and Suja Devi Vijayagangadharan, US-trained researchers at the Amrita Centre for Cyber Security that is part of Mata Amritanandamayi's Amrita University in Kerala's Kollam district.

The fetching coastline with its swaying palm trees and black sands fringes the vast University campus, where cutting edge scientific research is happening quietly, often through collaboration with peer groups abroad. Research here however is largely oriented toward practical applications that would benefit the greatest number - the Amritamitra safety device is one such that is to be announced during Amma's 60th birthday celebrations.

The personal safety device - designed at the suggestion of Mata Amritanandamayi - is just 3.5cm X 3.5cm and can be carried on one's person without attracting undue attention. The trigger may be built into the device or placed at another location on the individual's body, behind the ear or tucked at the waist, for example. This is how it operates:

This device will empower women - or the elderly, the physically challenged or children - to trigger communication with family and police when in distress. The device will remain inconspicuous to the offender and yet easily activated by the victim with multiple options to ensure stealthy and secure communication. With the ability to record conversations, and communicate immediately by the press of a button or using sms and voice calls to multiple destinations, this device also offers automated information on nearest police station, hospitals, fire stations to the victim to get immediate help. The device will also have ability to video tape events in the near future. It can work in indoor and outdoor environments with minimal power consumption.

Another device to be inaugurated during Amritavarsham60 -the 60th birthday celebrations of Amma on September 27, 2013 - is the one named Amritaspandan, a wireless device for heart patients that will alert the wearer and those on the alert list like hospital and family of any impending heart attack or failure, also revealing the location of the person.

A slew of initiatives and projects are to be announced during September 26-27 by the Mata Amritanandamayi Math (MAM) including the scheme to adopt 101 villages throughout India, which is being called the Amrita Self-Reliant Village Programme (Amrita Swasraya Gramam) where Ammachi Labs will set up e-learning facilities and every effort will be made to provide for education, skills development and healthcare. A Rs 50 crore project will take off towards disaster relief work in Uttarakhand, largely for housing, care for orphaned children and women and to provide educational services.

Also announced will be breakthroughs in cancer research by the Amrita Centre for Nanosciences and Molecular Medicine, a new tablet-based learning programme for literacy called Amrita RITE and a clutch of exciting online innovations for the benefit and protection of society.

Human brain tumour cells killed with drugs in mice

LONDON: Scientists have for the first time been able to completely erase human brain tumour cells in mice.

Researchers from Johns Hopkins University of Medicine in the US have discovered that weeks of treatment with a FDA-approved drug halted the growth of and ultimately left no detectable trace of brain tumour cells taken from adult human patients and regrown in mice.

The type of tumour targeted by the researchers eventually progresses to a subtype of glioblastoma multiform — the deadliest form of brain cancer — known to be highly progressive. They arise as a lower-grade Glioma and are initially treated with surgery alone, but eventually they progress to the more lethal form of tumour. Survival is longer than with glioblastoma, but it is found in younger patients, those under the age of 50.

The scientists targeted a mutation in the IDH1 gene first identified in human brain tumours called Gliomas by a team of Johns Hopkins cancer researchers in 2008. This mutation was found in around 80% of progressive forms of brain cancer.

"Usually in the lab, we're happy to see a drug slow down tumour growth. We never expect tumours to regress, but that is exactly what happened here. This therapy has worked amazingly well in these mice. We want to start discussing the parameters of a clinical trial to see if this will work in our human patients," said study leader Gregory Riggins, a professor of neurosurgery and oncology at Johns Hopkins.

The IDH1 gene produces an enzyme that regulates cell metabolism.

Indians going to Mars

REMINDS ONE OF THE COLONIZATION OF AUSTRALIA BY BRITAIN IN 1750-1900-THEY WERE SENT WITH  ONE WAY TICKET

 


Early Colonization of Australia
  In 1788 Britain sent prisoners to the Botany Bay penal colony. 

The First Fleet carried eleven ships full of prisoners.  The growing number of white prisoners caused problems for the native aborigines.  The aborigines suffered from diseases that were brought from the white prisoners.  In 1848 the governor of New South Wales did not accept anymore prisoners from Britain, but Western Australia, 1868, kept accepting.  Soon the prisoners made most of  population.Australia's It was hard for the prisoners at that time. The soil was not very suitable for farming therefore; the prisoners struggled for food.  Prisoners were put to service and they also raised sheep.
ship

Meet the Indians going to Mars



In the wise words of the 20-year-old Amulya Nidhi Rastogi, going to the moon was a fantastically-expensive piece of showing off, and not much more. "I must have been in class II when I read about man going to the moon and planting a flag there," he says. "But I couldn't understand why and I asked my father, 'Shouldn't we have done more? Maybe built a base there, set up a colony, a stepping stone to even more distant worlds?'"

Those old questions must still swirl around in his head for the slight — he's slim, about 5ft 6 inches, and wears glasses — third-year student of mechanical engineering at the World Institute of Technology in Gurgaon has applied to the Mars One Mission, which aims to establish a human colony on our galactic neighbour by the year 2023.

A rocket will take off from earth in late 2022 and, seven months later, will deposit four earthlings — two men and two women — on Mars. Once there, there will be no coming back, ever. Going to Mars then — there will of course be a huge, four-tiered vetting of the 165,000 men and women from around the world who have applied; applications are now closed — will mean staying there. But additional rockets will deposit four more permanent settlers there every two years.

Vinod Kotiya is married and has a one-year-old daughter. But that did not stop the 32-year-old manager with NTPC from applying to the mission on the day the Mars One website began accepting applications. That early start had Vinod climb up to number three on the popularity charts — visitors to the website are asked to vote for the applicants — which of course saw Vinod getting a very cold shoulder back home.

His wife, Priyanka, when he broke the news to her — sensibly, it could be argued, Vinod decided it would be better to tell her that he had applied to go to Mars after the fact rather than before — threatened to lie down in front of the rocket and not let it take off. Priyanka is somewhat more accepting of the move now that Vinod's popularity has climbed down to 15 on the charts; plus Vinod says that like a sensible Indian wife she has come to the conclusion that he will not make the cut and that, therefore, she has nothing to worry about.


[Amulya and his brother Tushar, who says he might write a book about his brother going to Mars]

None of this sounds very new, says Professor Radhika Chopra, who teaches sociology at Delhi university. Her speciality is urban anthropology. "Remember," she says, "when you look at the history of trans-national migration out of India, there has never been any certainty that those migrants will come back."

What she means to say is that when Indians have left these shores, they have always gone with the intention of settling down in the foreign lands they have travelled to.

Applicants to the Mars One Mission, in effect, plan on doing exactly the same thing — leave, and settle down elsewhere.

Of course, says Chopra, the Indians who have left the motherland have also stayed connected with her — either by shipping brides over after them or by other means. And that something similar, like a "Mars Facebook", will happen here too.

Vinod thinks so too. And says that while there are no plans for a return journey so far — Mars One says that is because the technology to take off from Mars and return to earth does not exist as yet, and that coming back from our neighbour will mean a very large increase in travel costs — that could change in the nine years still left for that first rocket to take off.

But Vinod, if you do get to go, Vaniya will be 10 then. Are you sure you will be able to leave her?

"Well," says Vinod, "she could come after me." And adds, "I have to go. The answers to the secrets of the universe will not be found here."



[Vinod with his wife Priyanka and their 1-year-old daughter Vaniya. Vinod says his daughter could follow him to Mars]

There are of course also more prosaic reasons for people wanting to go to Mars. Sameer Kumar Lowe says over the phone from Mumbai that his wife and son are dead set against him going, but that he's hoping for a salary and pension from the people putting together the Mars One Mission. (The project is being spearheaded by the Dutch entrepreneur Bas Landorp. And a bulk of the funds for the Mars One Mission will come from turning the selection process into reality television and broadcasting it.)

Sameer, who currently works with MMRDA as a rolling stock advisor on their metro and mono rail projects, he worked with Delhi Metro before this as a rolling stock engineer, and the Indian Air Force before that as a radar engineer, says he has been frustrated by the fact that he hasn't been able to build a house as yet.

And that a salary and a pension would make his wife and son, who has done a BTech but is currently unemployed, "financially secure". And of course, he adds with a laugh, the fame of being the first person on Mars will not hurt.

Sameer, who says he is "fifty plus", says he will stay fit enough for the job.

Whatever their reasons for wanting to go where no man has gone before, these men (of the 8,000 applicants from India, making them the fourth largest bloc after the Americans, the Chinese and the Brazilians, women make up an infinitesimal fraction) are in stellar (yes, pun intended) company.

Buzz Aldrin, the second man to walk on the moon, wrote recently in the New York Times that Nasa's Apollo programme to get to the moon was a space race between the US and the USSR, and not much more. And that we should close that chapter in the space exploration history books.

He then added: "Now I see the moon in a far different light — not as a destination but more a point of departure, one that places humankind on a trajectory to homestead Mars and become a two-planet species."

Oh, and of course, Aldrin's words also prove Amulya right.

A version of this article appeared in The Sunday Times of India on September 8. 
 comment:- "women make up an infinitesimal fraction"-shows level head thinking and analyzing by the fair sex
 
 well men are from mars -send them all off?no ,we need their help for the propagation of  humans of the future generations; till there are chances of survival of humans in mars


 

Ocean eddies are similar to black holes

Ocean eddies are similar to black holes
WASHINGTON: Some of the largest ocean eddies on Earth are mathematically equivalent to the mysterious black holes of space, scientists say.

These eddies are so tightly shielded by circular water paths that nothing caught up in them escapes.

George Haller, Professor of Nonlinear Dynamics at ETH Zurich, and Francisco Beron-Vera, Research Professor of Oceanography at the University of Miami, have developed a new mathematical technique to find water-transporting eddies with coherent boundaries.

The challenge in finding such eddies is to pinpoint coherent water islands in a turbulent ocean. The rotating and drifting fluid motion appears chaotic to the observer both inside and outside an eddy.

Haller and Beron-Vera were able to restore order in this chaos by isolating coherent water islands from a sequence of satellite observations. To their surprise, such coherent eddies turned out to be mathematically equivalent to black holes.

Black holes are objects in space with a mass so great that they attract everything that comes within a certain distance of them. Nothing that comes too close can escape, not even light.

But at a critical distance, a light beam no longer spirals into the black hole. Rather, it dramatically bends and comes back to its original position, forming a circular orbit.

Haller and Beron-Vera discovered similar closed barriers around select ocean eddies. In these barriers, fluid particles move around in closed loops ? similar to the path of light in a photon sphere. And as in a black hole, nothing can escape from the inside of these loops, not even water.

It is these barriers that help to identify coherent ocean eddies in the vast amount of observational data available. The very fact that such coherent water orbits exist amidst complex ocean currents is surprising, researchers said.

Because black-hole-type ocean eddies are stable, they function in the same way as a transportation vehicle - not only for micro-organisms such as plankton or foreign bodies like plastic waste or oil, but also for water with a heat and salt content that can differ from the surrounding water.

Haller and Beron-Vera have verified this observation for the Agulhas Rings, a group of ocean eddies that emerge regularly in the Southern Ocean off the southern tip of Africa and transport warm, salty water northwest.

The researchers identified seven Agulhas Rings of the black-hole type, which transported the same body of water without leaking for almost a year.

Haller points out that similar coherent vortices exist in other complex flows outside of the ocean. In this sense, many whirlwinds are likely to be similar to black holes as well.

The study was published in the Journal of Fluid Mechanics.

Spinning CDs to clean sewage water

READ MORE 60 Minutes
WASHINGTON:Wondering what to do with your obsolete audio CDs? Researchers have come up with a practical application: they can be used to break down sewage.

"Optical disks are cheap, readily available, and very commonly used," said Din Ping Tsai, a physicist at National Taiwan University. Close to 20 billion disks are already manufactured annually, the researchers noted.

Tsai and his colleagues used the large surface area of optical disks as a platform to grow tiny, upright zinc oxide nanorods about a thousandth the width of a human hair. Zinc oxide is an inexpensive semiconductor that can function as a photocatalyst, breaking apart organic molecules like the pollutants in sewage when illuminated with UV light.

As the disks are durable and able to spin quickly, contaminated water that drips onto the device spreads out in a thin film that light can easily pass through, speeding up the degradation. The team's complete water treatment device is approximately one cubic foot in volume. The device also consists of a UV light source and a system that recirculates the water to further break down the pollutants.

The team tested the reactor with a solution of methyl orange dye. After treating a half-litre solution for 60 minutes, they found that over 95% of the contaminants had been broken down.

the tree of knowledge-eureka

Black hole at heart of our galaxy erupted 2 million years ago

WASHINGTON: Scientists have for the first time found that a dormant volcano - a supermassive black hole - lying at the heart of our Milky Way galaxy last erupted two million years ago.

Astronomers have long suspected such an outburst occurred, but this is the first time it has been dated.

The evidence comes from a lacy filament of gas, mostly hydrogen, called the Magellanic Stream. This trails behind our galaxy's two small companion galaxies, the Large and Small Magellanic Clouds.

"For twenty years we've seen this odd glow from the Magellanic Stream," said lead researcher professor Joss Bland-Hawthorn at the University of Sydney, Australia, and a Fellow at the Australian Astronomical Observatory.

"We didn't understand the cause. Then suddenly we realised it must be the mark, the fossil record, of a huge outburst of energy from the centre of our galaxy," he said.
"It's been long suspected that our galactic centre might have sporadically flared up in the past. These observations are a highly suggestive 'smoking gun'," said Martin Rees, Astronomer Royal, who was one of the first people to suggest that black holes generate the power seen coming from quasars and galaxies with 'active' centres.

The galaxy's supermassive black hole is orbited by a swarm of stars whose paths help measure the black hole's mass: four million times the mass of the Sun, 'phys.org' reported.

The region around the black hole, called Sagittarius A, pours out radio waves, infrared, X-rays and gamma rays.

Infrared and X-ray satellites have seen a powerful 'wind' (outflow) of material from this central region. Antimatter boiling out has left its signature. And there are the 'Fermi bubbles' - two huge hot bubbles of gas billowing out from the galactic centre, seen in gamma-rays and radio waves.

"All this points to a huge explosion at the centre of our galaxy. What astronomers call a Seyfert flare," said team member Dr Philip Maloney of the University of Colorado in Boulder, US.

At a workshop at Stanford University in California earlier this year, researchers realised the Stream could be holding the memory of the galactic centre's past.

Struck by the fiery breath of Sagittarius A, the Stream is emitting light, much as particles from the Sun hit our atmosphere and trigger the coloured glows of the aurorae - the Northern and Southern Lights.

The brightest glow in the Stream comes from the region nearest the galactic centre.

"Geometry, the amount of energy from the original flare from Sagittarius A, the time the flare would take to travel to the Magellanic Stream, the rate at which the Stream would have cooled over time - it all fits together, it all adds up," said team member Dr Greg Madsen of the University of Cambridge in UK.