Robot Walks on Water

Mimicking Insects to Avoid Sinking

Using Surface Tension

July 1, 2006 — A new robot made of ultralight carbon-fiber can stand or slowly walk on water. The principle it uses is borrowed from insects — surface tension tends to prevent the water’s surface from breaking, and the robot’s legs from sinking in.

PITTSBURGH — Nature inspires many things, from fashion to perfume to furniture. Now, technology gets a little inspiration.

After watching tiny bugs like these walk on water, Carnegie Mellon University mechanical engineer Metin Sitti wanted one of his own.

“We tried to make a robot to simulate the insect,” he tells DBIS. He tried and succeeded. This new tiny, lightweight, spindly legged creature is a robot that can propel itself across water in all directions. It can turn even sharp corners like the insect does, so it’s very agile.

The robot’s body is made of a super-light carbon fiber material. Its steel legs are coated with non-stick Teflon to repel water. A tiny battery gives it power.

“Right now we move by five centimeters per second, and the real insect can go up to one meter per second. So we are like around 20-times less speed,” Sitti says.

It might be slower, but just like insects, the robot doesn’t float. It stands on top of water thanks to the physics of surface tension. The surface is so strong that the robot’s feet only dent the water without breaking the surface while supporting the weight of the robot without sinking.

“When they put their legs on the surface of the water surface, they repel each other,” Sitti says. “And that repulsion can lift the body because it’s so light bodyweight.”

In the near future, Sitti says his creation could carry sensors to detect toxins in water supplies. “We can make many of them, like tens or hundreds of them, and cover a wide range and give you constant, continuous, water quality report,” he says.

Researchers have already received interest in the robot as an educational toy, to educate students and the public about water surface effects, and to provide entertainment.

BACKGROUND: Researchers at Carnegie Mellon University have built a tiny robot that can walk on water, much like insects known as water skimmers, water skaters, pond skaters or Jesus bugs. Although it is still a prototype, its creators believe it could one day be equipped with biochemical sensors that monitor water quality. It could be used with cameras for spying, search and rescue operations, or for exploration. The robot might also be outfitted with bacteria to help break down pollutants in the environment.

THE JESUS LIZARD: In 2004, Harvard researchers discovered how basilisk lizards (sometimes called “Jesus lizards” because they appear to walk on water) manage to run across the surface of water on their two hind legs, with front arms outstretched. They move at speeds faster than 1.5 meters per second, comparable to a human running 65 MPH. The lizard first slaps the water with its web-like foot, strokes downward with an elliptical motion to create an air pocket, and then pulls its foot out of the water by curling its toes inward. By repeating this sequence up to 10 times a second, it generates sufficient forward thrust and lift to run on water without tipping over or sinking.

WHAT IS BIOMIMICRY: Biomimicry is a field in which scientists, engineers, and even architects study models and concepts found in nature, and try to use them to design new technologies. It as a design principle that seeks sustainable solutions to human problems by emulating nature’s time-tested patterns and strategies. Nature fits form to function, rewards cooperation, and banks on diversity. For instance, the Eastgate Building in Harare, Zimbabwe, is the country’s largest commercial and shopping complex, and yet it uses less than 10 percent of the energy consumed by a conventional building of its size, because there is no central air conditioning and only a minimal heating system. The design follows the cooling and heating principles used in the region’s termite mounds.

The Institute of Electrical and Electronics Engineers, Inc., contributed to the information contained in the TV portion of this report.

Sourced & published by Henry Sapiecha


New ‘ocean’ being born in Africa


LONDON (UPI) — A new ocean is being born in Africa that will eventually split the continent in two, British researchers say.

Scientists at Britain’s Royal Society say a 40-mile crack in the Earth opened in Ethiopia in 2005 and has been growing ever since, the BBC reported Friday.

The crack will eventually became the sea bed of a new ocean that will divide Africa in two, though the process will require about 10 million years, scientists say.

Used to understanding planetary changes on timescales involving millions of years, scientists say the crack in the remote Afar region of Ethiopia is dramatic in the speed at which it is growing.

The 40-mile crack opened to a width of 22 feet in just 10 days, they say.

Ultimately, they say, the horn of Africa will split from the continent, and the crack, in a region below sea level, will fill with salt water.

“It will pull apart, sink down deeper and deeper and eventually … parts of southern Ethiopia, Somalia will drift off, create a new island, and we’ll have a smaller Africa and a very big island that floats out into the Indian Ocean,” said Dr. James Hammond, a seismologist from the University of Bristol.

Copyright 2010 by United Press International

Sourced & published by Henry Sapiecha

Physics of the ‘Bends’:

New Study Helps Explain

Decompression Sickness

Science(June 28, 2010) — As you go about your day-to-day activities, tiny bubbles of nitrogen come and go inside your tissues. This is not a problem unless you happen to experience large changes in ambient pressure, such as those encountered by scuba divers and astronauts. During large, fast pressure drops, these bubbles can grow and lead to decompression sickness, popularly known as “the bends.”

A study in the Journal of Chemical Physics, which is published by the American Institute of Physics (AIP), may provide a physical basis for the existence of these bubbles, and could be useful in understanding decompression sickness.

A physiological model that accounts for these bubbles is needed both to protect against and to treat decompression sickness. There is a problem though. “These bubbles should not exist,” says author Saul Goldman of the University of Guelph in Ontario, Canada.

Because they are believed to be composed mostly of nitrogen, while the surrounding atmosphere consists of both nitrogen and oxygen, the pressure of the bubbles should be less than that of the surrounding atmosphere. But if this were so, they would collapse.

“We need to account for their apparent continuous existence in tissues in spite of this putative pressure imbalance,” says Goldman.

If, as is widely believed, decompression sickness is the result of the growth of pre-existing gas bubbles in tissues, those bubbles must be sufficiently stable to have non-negligible half-lives. The proposed explanation involves modeling body tissues as soft elastic materials that have some degree of rigidity. Previous models have focused on bubble formation in simple liquids, which differ from elastic materials in having no rigidity.

Using the soft-elastic tissue model, Goldman finds pockets of reduced pressure in which nitrogen bubbles can form and have enough stability to account for a continuous presence of tiny bubbles that can expand when the ambient pressure drops. Tribonucleation, the phenomenon of formation of new gas bubbles when submerged surfaces separate rapidly, provides the physical mechanism for formation of new gas bubbles in solution. The rapid separation of adhering surfaces results in momentary negative pressures at the plane of separation. Therefore, while these tiny bubbles in elastic media are metastable, and do not last indefinitely, they are replaced periodically. According to this picture, tribonucleation is the source, and finite half-lives the sink, for the continuous generation and loss small gas bubbles in tissues.

Sourced & published by Henry Sapiecha

Hurricane winds can rupture undersea pipes


WASHINGTON (UPI) — U.S. researchers say they’ve determined undersea forces produced by strong hurricanes are powerful enough to rupture underwater oil pipelines.

The scientists at the U.S. Naval Research Laboratory said the pipelines could crack or rupture unless they are buried or their supporting foundations are built to withstand hurricane-induced currents.

“Major oil leaks from damaged pipelines could have irreversible impacts on the ocean environment,” the researchers said, noting a hurricane’s winds can raise waves 66 feet or more above the ocean surface.

Based on unique measurements taken during a powerful hurricane, the researchers said their study is the first to show hurricanes propel underwater currents with enough force to dig up the seabed, potentially creating underwater mudslides and damaging pipes or other equipment resting on the bottom.

They said they’re not sure what strengths of forces underwater oil pipelines are built to withstand. However, “Hurricane stress is quite large, so the oil industry better pay attention,” said Hemantha Wijesekera, who led the study.

The findings are to appear in the June10 issue of the journal Geophysical Research Letters.

Sourced and published  by Henry Sapiecha


Why Icicles Are Long And Thin

Mathematical Physics Explains

How Icicles Grow

When droplets of melted snow drip down an icicle, they release small amounts of heat as they freeze. Heated air travels upwards and helps slow down the growth of the icicle’s top, while the tip is growing rapidly. Knowledge of the mathematical equations that govern icicle growth — the same that apply to stalactites — could help in the prevention of icicle formation on power lines.

Icicles can be dangerous and deadly, yet they can create some of the most amazing winter scenes. And for scientists, those winter scenes are playgrounds for discovery.

It’s on those playgrounds that experts in physics and mathematics are building their theories on what it takes to create an icicle.

We all know icicles form when melting snow begins dripping down a surface. But what scientists didn’t know is how their shape is formed. What makes each icicle different?

University of Arizona Physicist Martin Short turned to mathematics to find out.

“Icicles have a certain mathematical shape, and this mathematical shape is universal among icicles,” Short tells DBIS.

So what is the math behind an icicle?

“Here I’ve drawn the profile of an icicle. Here is the height, and here’s the radius … Here’s the profile here, and I’ve written the formula here. The height is proportional to the radius to the four-thirds,” he says.

What does the formula have to do with an icicle’s shape? “It kind of looks like a carrot,” says Short. “It starts out flat and then sort of up as you go.”

As water drips onto an icicle and freezes, it releases heat. The warm air rises up the sides of the icicle. Short says that warm air layer acts like a blanket that’s an insulator, and so the blanket is very thin near the tip and thick at the top. That allows the top to grow very slowly and the tip to grow rapidly — creating a long, thin icicle.

It’s the same equation scientists use to study stalactites in caves, but instead of water, stalactites are formed by the buildup of calcium left after the water evaporates.

“If we know the mechanisms by which stalactites form, well, we could better preserve our natural caves that we have here, and try to stop them from eroding,” Short says.

And now that scientists know how icicles are made, it could lead to breakthroughs to prevent them from forming on power lines and trees.

Sharks Can Really Sniff out Their Prey,

and This Is How They Do It

Science (June 10, 2010) — It’s no secret that sharks have a keen sense of smell and a remarkable ability to follow their noses through the ocean, right to their next meal. Now, researchers reporting online on June 10th in Current Biology, have figured out how the sharks manage to keep themselves on course.

It turns out that sharks can detect small delays, no more than half a second long, in the time that odors reach one nostril versus the other, the researchers report. When the animals experience such a lag, they will turn toward whichever side picked up the scent first.

“The narrow sub-second time window in which this bilateral detection causes the turn response corresponds well with the swimming speed and odor patch dispersal physics of our shark species,” known as Mustelus canis or the smooth dogfish, said Jayne Gardiner of the University of South Florida. All in all, it means that sharks pick up on a combination of directional cues, based on both odor and flow, to keep themselves oriented and ultimately find what they are looking for.

If a shark experiences no delay in scent detection or a delay that lasts too long — a full second or more — they are just as likely to make a left-hand turn as they are to make a right.

These results refute the popular notion that sharks and other animals follow scent trails based on differences in the concentration of odor molecules hitting one nostril versus the other. It seems that theory doesn’t hold water when one considers the physics of the problem.

“There is a very pervasive idea that animals use concentration to orient to odors,” Gardiner said. “Most creatures come equipped with two odor sensors — nostrils or antennae, for example — and it has long been believed that they compare the concentration at each sensor and then turn towards the side receiving the strongest signal. But when odors are dispersed by flowing air or water, this dispersal is incredibly chaotic.”

Indeed, Gardiner explained, recent studies have shown that concentrations of scent molecules could easily mislead. Using dyes that light up under laser light, scientists found that there can be sudden peaks in the concentrations of molecules even at a distance from their source.

Gardiner’s team suggests that the findings in the small shark species they studied may help to explain the evolution of the wide and flat heads that make hammerhead sharks so recognizable. One idea has held that the characteristic hammerhead may lend the animals a better sense of smell. But studies hadn’t shown their noses to be all that remarkable, really. For instance, they don’t respond to odors at concentrations lower than other sharks. The new findings suggest that the distance between their nostrils could be the key.

“If you consider an animal encountering an odor patch at a given angle, an animal with more widely spaced nostrils will have a greater time lag between the odor hitting the left and right nostrils than an animal with more closely spaced nostrils,” Gardiner said. “Hammerheads may be able to orient to patches at a smaller angle of attack, potentially giving them better olfactory capabilities than pointy-nosed sharks.” That’s a theory that now deserves further testing.

In addition to giving insights into the evolution and behavior of sharks, the findings might also lead to underwater robots that are better equipped to find the source of chemical leaks, like the oil spill that is now plaguing the Gulf Coast, according to the researchers.

“This discovery can be applied to underwater steering algorithms,” Gardiner said. “Previous robots were programmed to track odors by comparing odor concentrations, and they failed to function as well or as quickly as live animals. With this new steering algorithm, we may be able to improve the design of these odor-guided robots. With the oil spill in the Gulf of Mexico, the main oil slick is easily visible and the primary sources were easy to find, but there could be other, smaller sources of leaks that have yet to be discovered. An odor-guided robot would be an asset for these types of situations.”

The researchers include Jayne M. Gardiner, University of South Florida, Tampa, FL, Center for Shark Research, Mote Marine Laboratory, Sarasota, FL; and Jelle Atema, Boston University Marine Program, Boston, MA, Marine Biological Laboratory, Woods Hole, MA, Woods Hole Oceanographic Institution, Woods Hole, MA.

Sourced and published by Henry Sapiecha 11th June 2010

Clam Cleanup

Biologists Clam Up Waterways

To Determine Sources Of Pollution

January 1, 2009 — Biologists are able to determine the sources of toxins in water by using clams as pollutant traps. Clams naturally clean water by feeding absorbing toxins in their tissues as they draw in water. By placing the clams downstream of industrial parks and highways, they can be analyzed for pollutants. Biologists open the clams after exposure to these waters and detach them from their shells– various lab tests reveal contaminants in the waterway.

See also:
Plants & Animals

Many of our streams and rivers are contaminated with pollutants like pesticides, lead, arsenic and PCBs. It’s a problem that’s costly to clean up. Scientists are using a new, inexpensive way to fix the problem.

Lurking in many rivers and streams are contaminants. Some you can see, and some you can’t. Hidden chemicals ruin waterways and everything in it. To clean things up, biologists are teaming up with local high school students to dredge up clams to use as tiny detectives. They help by finding the source of toxic leaks.

“We’re using them as pollutant traps,” said Harriette Phelps, Ph.D., a biologist at the University of the District of Columbia in Washington, D.C.

Students put the clams in streams that lead to rivers. Clams then suck in water swept down from industrial parks and highways.

“It’s been a great experience to actually come and see them and be the ones to pick them up out of the water,” student Caitlin Virta said.

Clams clean the water as they feed, absorbing toxins in their tissues. The clams are collected back from streams. Then, scientists pry open the clams and detach them from their shell. Later, lab tests reveals the clam’s secret — the kinds and quantities of pollutants in the water.

“We can trace them back to sources, and then hopefully we can go from there and get rid of the sources,” Dr. Phelps said.

The clams detected a banned pesticide in Maryland, believed buried years ago and now slowly leaking. “I thought it was really cool how you could tell the health of a stream from analyzing clam leftovers,” Virta said.

It’s a cool way to clean up the environment.

BIOACCUMULATION AND CLAMS: Clams are filter-feeders, meaning they draw water into their shells, remove the food they find, and then draw in more food-rich water to continue feeding. This means that lots of water works its way through their shells. The muscle of the clam gathers not only food, but other material suspended in water during this process, which can lead to the accumulation of toxins and pollutants. Bioaccumulation is the term for toxins and pollutants that collect in the tissue of an organism. Biomagnification is a related term, referring to the transfer of such substances from prey to predator. If a prey animal bioaccumulates toxins in its body, then its predator, after consuming many of the smaller animals will accumulate many, many times the amount of the toxin in any one of their prey.

SECONDARY STANDARDS: Even if your tap water meets the EPA’s basic requirement for safe drinking water, some people still object to the taste, smell or appearance of their water. These are aesthetic concerns, however, and therefore fall under the EPA’s voluntary secondary standards. Some tap water is drinkable, but may be temporarily clouded because of air bubbles, or have a chlorine taste. A bleach-like taste can be improved by letting the water stand exposed to the air for a while.

The American Geophysical Union contributed to the information

Sourced and published by Henry Sapiecha 7th June 2010


SEX IN THE OCEAN IS GREAT FOR THESE OYSTERS

NEWLY INVENTED OYSTER BEDS ON WHICH OYSTERS GROW

BRING A NEW MEANING TO THE TERM ‘SEA BED’


Hi, this is Rex Ellis.

I am thrilled because my Harvest Post has now reached production stage! I have been developing this idea since 2006 and have had  great feed back and a lot of encouragement by the industry.
Have a look at the post with the baskets in the pic  and see for yourself. Today we have been out to sea and have sank the post within seconds into the sea bed. It was indeed very difficult to remove it again. The harvest post is very strong and can carry multiple baskets with single compartments in order to grow shellfish stress free and in a shorter time than so far possible thanks to 48 single compartments per basket.

I am ready to take your orders, please contact me for a quote on a custom made solution for your needs.

THE PRODUCT IS GUARANTEED TO HAVE A LIFE OF AT LEAST 25YEARS

…………………………………………………………………………………………………………………….

HARVEST POST INVENTOR

[OYSTER GROWING]

Rex Ellis

About Me

I have worked in the plastic industry for over 20 years. We developed different products like tanks and a plastic picket fence with an inbuilt watering system. The idea about the revolutionising way of growing shellfish came to me when I saw how labour intensive and physically demanding the growing of shellfish is. Because I love eating oysters, scallops and mussels myself I want to see the highest quality of shellfish grown especially in New Zealand, my home country and Australia, my chosen place to live

0407 820 030
rexellisharvestpost@gmail.com

Sourced and published by Henry Sapiecha 4th May 2010

Renewable Energy:

Inexpensive Metal Catalyst

Can Effectively Generate

Hydrogen from Water

Science (May 1, 2010) — Hydrogen would command a key role in future renewable energy technologies, experts agree, if a relatively cheap, efficient and carbon-neutral means of producing it can be developed. An important step towards this elusive goal has been taken by a team of researchers with the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley. The team has discovered an inexpensive metal catalyst that can effectively generate hydrogen gas from water.

“Our new proton reduction catalyst is based on a molybdenum-oxo metal complex that is about 70 times cheaper than platinum, today’s most widely used metal catalyst for splitting the water molecule,” said Hemamala Karunadasa, one of the co-discoverers of this complex. “In addition, our catalyst does not require organic additives, and can operate in neutral water, even if it is dirty, and can operate in sea water, the most abundant source of hydrogen on earth and a natural electrolyte. These qualities make our catalyst ideal for renewable energy and sustainable chemistry.”

Karunadasa holds joint appointments with Berkeley Lab’s Chemical Sciences Division and UC Berkeley’s Chemistry Department. She is the lead author of a paper describing this work that appears in the April 29, 2010 issue of the journal Nature, titled “A molecular molybdenum-oxo catalyst for generating hydrogen from water.” Co-authors of this paper were Christopher Chang and Jeffrey Long, who also hold joint appointments with Berkeley Lab and UC Berkeley. Chang, in addition, is also an investigator with the Howard Hughes Medical Institute (HHMI).

Hydrogen gas, whether combusted or used in fuel cells to generate electricity, emits only water vapor as an exhaust product, which is why this nation would already be rolling towards a hydrogen economy if only there were hydrogen wells to tap. However, hydrogen gas does not occur naturally and has to be produced. Most of the hydrogen gas in the United States today comes from natural gas, a fossil fuel. While inexpensive, this technique adds huge volumes of carbon emissions to the atmosphere. Hydrogen can also be produced through the electrolysis of water — using electricity to split molecules of water into molecules of hydrogen and oxygen. This is an environmentally clean and sustainable method of production — especially if the electricity is generated via a renewable technology such as solar or wind — but requires a water-splitting catalyst.

Nature has developed extremely efficient water-splitting enzymes — called hydrogenases — for use by plants during photosynthesis, however, these enzymes are highly unstable and easily deactivated when removed from their native environment. Human activities demand a stable metal catalyst that can operate under non-biological settings.

Metal catalysts are commercially available, but they are low valence precious metals whose high costs make their widespread use prohibitive. For example, platinum, the best of them, costs some $2,000 an ounce.

“The basic scientific challenge has been to create earth-abundant molecular systems that produce hydrogen from water with high catalytic activity and stability,” Chang says. “We believe our discovery of a molecular molybdenum-oxo catalyst for generating hydrogen from water without the use of additional acids or organic co-solvents establishes a new chemical paradigm for creating reduction catalysts that are highly active and robust in aqueous media.”

The molybdenum-oxo complex that Karunadasa, Chang and Long discovered is a high valence metal with the chemical name of (PY5Me2)Mo-oxo. In their studies, the research team found that this complex catalyzes the generation of hydrogen from neutral buffered water or even sea water with a turnover frequency of 2.4 moles of hydrogen per mole of catalyst per second.

Long says, “This metal-oxo complex represents a distinct molecular motif for reduction catalysis that has high activity and stability in water. We are now focused on modifying the PY5Me ligand portion of the complex and investigating other metal complexes based on similar ligand platforms to further facilitate electrical charge-driven as well as light-driven catalytic processes. Our particular emphasis is on chemistry relevant to sustainable energy cycles.”

This research was supported in part by the DOE Office of Science through Berkeley Lab’s Helios Solar Energy Research Center, and in part by a grant from the National science Foundation.

Sourced and published by Henry Sapiecha 2nd May 2010

Microbes galore in seas; “spaghetti” mats Pacific

HUGE MATS OF TOXIC BACTERIA ON SEA BEDS

By Alister Doyle, Environment CorrespondentPosted 2010/04/18 at 1:09 pm EDT

OSLO, Apr. 18, 2010 (Reuters) — The ocean depths are home to myriad species of microbes, mostly hard to see but including spaghetti-like bacteria that form whitish mats the size of Greece on the floor of the Pacific, scientists said on Sunday.

The survey, part of a 10-year Census of Marine Life, turned up hosts of unknown microbes, tiny zooplankton, crustaceans, worms, burrowers and larvae, some of them looking like extras in a science fiction movie and underpinning all life in the seas.

“In no other realm of ocean life has the magnitude of Census discovery been as extensive as in the world of microbes,” said Mitch Sogin of the Marine Biological Laboratory in Woods Hole, Massachusetts, head of the marine microbe census.

The census estimated there were a mind-boggling “nonillion” — or 1,000,000,000,000,000,000,000,000,000,000 (30 zeroes) — individual microbial cells in the oceans, weighing as much as 240 billion African elephants, the biggest land animal.

Getting a better idea of microbes, the “hidden majority” making up 50 to 90 percent of biomass in the seas, will give a benchmark for understanding future shifts in the oceans, perhaps linked to climate change or pollution.

Among the biggest masses of life on the planet are carpets on the seabed formed by giant multi-cellular bacteria that look like thin strands of spaghetti. They feed on hydrogen sulphide in oxygen-starved waters in a band off Peru and Chile.

“Fishermen sometimes can’t lift nets from the bottom because they have more bacteria than shrimp,” Victor Gallardo, vice chair of the Census Scientific Steering Committee, told Reuters. “We’ve measured them up to a kilo (2.2 lbs) per square meter.”

GHOSTLY MATS

The census said they carpeted an area the size of Greece — about 130,000 sq km (50,000 sq miles) or the size of the U.S. state of Alabama. Toxic to humans, the bacteria are food for shrimp or worms and so underpin rich Pacific fish stocks.

The bacteria had also been found in oxygen-poor waters off Panama, Ecuador, Namibia and Mexico as well as in “dead zones” under some salmon farms. They were similar to ecosystems on earth that thrived from 2.5 billion to 650 million years ago.

Overall in the oceans, up to a billion microbe species may await identification under the Census, an international 10-year project due for completion in October 2010.

Tiny life was found everywhere, including at thermal vents with temperatures at 150 Celsius (300F) or in rocks 1,626 meters (5,335 ft) below the sea floor. Many creatures lack names or are hard to pronounce like loriciferans, polychaetes or copepods.

One major finding was that rare microbes are often found in samples where they can be outnumbered 10,000 to one by more common species. Isolated microbes may be lying in wait for a change in conditions that could bring a population boom.

Ann Bucklin, head of the Census of Marine Zooplankton that include tiny transparent crustaceans or jellyfish, said the seas were barely studied even by the census.

“Seventy percent of the oceans are deeper than 1,000 meters,” Bucklin, of the University of Connecticut, told Reuters. “The deep layer is the source of the hidden diversity.”

Paul Snelgrove, of Memorial University in Canada, said one sample in the South Atlantic in an area the size of a small bathroom — 5.4 square meters — turned up 700 species of copepod, a type of crustacean, 99 percent of them unfamiliar.

Just finding Latin names for each find will be hard. Scientists had rejected the idea of raising funds by letting people pay to have a marine “bug” named after them.

Sourced and published by Henry Sapiecha 21st April 2010

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