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Parasite Inspires Surgical Patch

Parasite Inspires Surgical Patch | Communicating Science | Scoop.it

By mimicking a technique used by an intestinal parasite of fish, researchers have developed a flexible patch studded with microneedles that holds skin grafts in place more strongly than surgical staples do. After burrowing into the walls of a fish's intestines, the spiny-headed worm Pomphorhynchus laevis inflates its proboscis to better embed itself in the soft tissue. In the new patch (sample shown in main image), the stiff polystyrene core of the 700-micrometer-tall needles (inset) penetrates the tissue; then a thin hydrogel coating on the tip of each needle—a coating based on the material in disposable diapers that expands when it gets wet—swells to help anchor the patch in place. In tests using skin grafts, adhesion strength of the patch was more than three times higher than surgical staples, the researchers report online today in Nature Communications. Because the patch doesn't depend on chemical adhesives for its gripping power, there's less chance for patients to have an allergic reaction. And because the microneedles are about one-quarter the length of typical surgical staples, the patches cause less tissue damage when they're removed, the researchers contend. Besides holding grafts in place, the patch could be used to hold the sides of a wound or an incision together—even, in theory, ones inside the body if a slowly dissolving version of the patch can be developed. Moreover, the researchers say, the hydrogel coating holds promise as a way to deliver proteins, drugs, or other therapeutic substances to patients.


Via Dr. Stefan Gruenwald
The Science & Education team's insight:

As someone who has sat and removed surgical staples this is a nice piece of technology

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Topaz Solar Farm, California : Image of the Day

Topaz Solar Farm, California : Image of the Day | Communicating Science | Scoop.it
The new 550 megawatt facility in California produces enough electricity to power 180,000 homes.

 

Nine million cadmium telluride solar modules now cover part of Carrizo Plain in southern California. The modules are part of Topaz Solar Farm, one of the largest photovoltaic power plants in the world. At 9.5 square miles (25.6 square kilometers), the facility is about one-third the size of Manhattan island, or the equivalent of 4,600 football fields.

Construction at Topaz began in 2011. The plant was mostly complete by November 2014, when it was turned on and began to generate electricity. By February 2015, all construction activity ended and plant operator BHE Renewable was set to announce that the project was officially complete. When operating at full capacity, the 550-megawatt plant produces enough electricity to power about 180,000 homes. According to BHE estimates, that is enough to displace about 407,000 metric tons of carbon dioxide per year, the equivalent of taking 77,000 cars off the road.

From the ground level, the scope of the facility is difficult to comprehend. Visitors to Topaz describe rows of solar panels that seem to stretch endlessly into the horizon. This satellite image, captured on January 2, 2015, by the Operational Land Imager on Landsat 8, helps put the facility into perspective. Solar arrays appear gray and charcoal. The surrounding farmland and grasslands appear brown and green. The power plant is situated within a plain flanked by the Caliente Range to the west and the Temblor Range to the east.

Topaz’s solar modules are mounted together on panels supported by steel columns; the structure holds the modules about 5 feet (1.5 meters) above the ground. Rows of panels are laid in a way that form large geometric shapes that are defined in part by the presence of access roads, stream beds, and preexisting infrastructure. The northernmost portions of the solar farm, which are close to a transmission line, were built first.

Mid American Renewables and Gunther Portfolio have published interesting aerial video and photographs that show additional views of the plant at various stages of construction.

References and Related ReadingABC News (2014, December 30) Topaz Solar Farm. Accessed February 27, 2015.BHE Solar Topaz Solar Farms. Accessed February 27, 2015.First Solar Topaz Solar Farm. Accessed February 27, 2015.Gigaom (2015, January 20) How the rise of a mega solar panel farm shows us the future of energy. Accessed February 27, 2015.County of San Luis Obsipo (2011, March) Topaz Solar Farm Project. Accessed February 27, 2015.Department of Energy (2011, August) Final Environmental Impact Statement. Accessed February 27, 2015.Gunter Portfolio (2012, November 21) Solar Barnstorming the Carrizo Plain. Accessed February 27, 2015.EIEE Spectrum (2015, February 25) Topaz Turns On 9 Million Solar Panels. Accessed February 27, 2015.Mid American Renewables (2015, February 25) Topaz Solar Farms Construction Site. Accessed February 27, 2015.
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The NASA Earth Observatory is always worth a look.

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Huge ocean confirmed underneath solar system’s largest moon

Huge ocean confirmed underneath solar system’s largest moon | Communicating Science | Scoop.it

 

Ganymede’s underground ocean contains more water than all the oceans on Earth

 

The solar system’s largest moon, Ganymede, in orbit around Jupiter, harbors an underground ocean containing more water than all the oceans on Earth. Scientists were already fairly confident in the ocean’s existence, based on the moon’s smooth icy surface—evidence of past resurfacing by the ocean—and other observations by the Galileo spacecraft, which made a handful of flybys in the 1990s. But new observations by the Hubble Space Telescope, published online today in the Journal of Geophysical Research: Space Physics, remove any remaining doubt. Ganymede now joins Jupiter’s Europa and two moons of Saturn, Titan and Enceladus, as moons with subsurface oceans—and good places to look for life. Ceres, the largest object in the asteroid belt, may also have a subsurface ocean. The new results come from Hubble’s observations of Ganymede’s magnetic field, which produces two auroral belts (pictured) that can be detected in the ultraviolet. Because of interactions with Jupiter’s own magnetic field, these belts rock back and forth. However, there is a third magnetic field in the mix—one emanating from the electrically conductive, saltwater ocean and induced by Jupiter’s field—that counterbalances Jupiter’s field and reduces the rocking of the auroral belts. The Hubble study suggests that the ocean can be no deeper than 330 kilometers below the surface.

The Science & Education team's insight:

Oceans are the theme of the day.

 

Another report: http://www.planetary.org/blogs/emily-lakdawalla/2015/03121716-ganymede-ocean.html

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Astronomy in Indigenous knowledge

Astronomy in Indigenous knowledge | Communicating Science | Scoop.it

Indigenous Australians have been developing complex knowledge systems for tens of thousands of years. These knowledge systems - which seek to understand, explain, and predict nature - are passed to successive generations through oral tradition.

As Ngarinyin elder David Bungal Mowaljarlai explains: “Everything under creation […] is represented in the ground and in the sky.” For this reason, astronomy plays a significant role in these traditions.

Western science and Indigenous knowledge systems both try to make sense of the world around us but tend to be conceptualised rather differently. The origin of a natural feature may be explained the same in Indigenous knowledge systems and Western science, but are couched in very different languages.

A story recounted by Aunty Mavis Malbunka, a custodian of the Western Arrernte people of the Central Desert, tells how long ago in the Dreaming, a group of women took the form of stars and danced a corroboree (ceremony) in the Milky Way.

One of the women put her baby in a wooden basket (coolamon) and placed him on the edge of the Milky Way. As the women danced, the baby slipped off and came tumbling to Earth. When the baby and coolamon fell, they hit the ground, driving the rocks upward. The coolamon covered the baby, hiding him forever, and the baby’s parents – the Morning and Evening Stars – continue to search for their lost child today.

If you look at the evening winter sky, you will see the falling coolamon in the sky, below the Milky Way, as the arch of stars in the Western constellation Corona Australis – the Southern Crown.

The place where the baby fell is a ring-shaped mountain range 5km wide and 150m high. The Arrernte people call it Tnorala. It is the remnant of a giant crater that formed 142 million years ago, when a comet or asteroid struck the Earth, driving the rocks upward.

 Tnorala (Gosses Bluff crater). Dementia/Flickr, CC BY-SA

Click to enlargePredicting seasonal change

When the Pleiades star cluster rises just before the morning sun, it signifies the start of winter to the Pitjantjatjara people of the Central Desert and tells them that dingoes are breeding and will soon be giving birth to pups.

The evening appearance of the celestial shark, Baidam traced out by the stars of the Big Dipper (in Ursa Major) tells Torres Strait Islanders that they need to plant their gardens with sugarcane, sweet potato and banana.

When the nose of Baidam touches the horizon just after sunset, the shark breeding season has begun and people should stay out of the water as it is very dangerous!

Torres Strait Islanders use constellations, such as the shark ‘Baidam’ pictured here, for practical purposes. Brian Robinson

Torres Strait Islanders' close attention to the night sky is further demonstrated in their use of stellar scintillation (twinkling), which enables them to determine the amount of moisture and turbulence in the atmosphere. This allows them to predict weather patterns and seasonal change. Islanders distinguish planets from stars because planets do not twinkle.

In Wergaia traditions of western Victoria, the people once faced a drought and food was scarce. Facing starvation, a woman named Marpeankurric set out in search of tucker for the group. After searching high and low, she found an ant nest and dug up thousands of nutritious ant larvae, called bittur.

This sustained the people through the winter drought. When she passed away, she ascended to the heavens and became the star Arcturus. When Marpeankurric rises in the evening, she tells the people when to harvest the ant larvae.

Arcturus (Marpeankurric – on the lower left) and the Milky Way over Lake Hart. Alex Cherney

Click to enlarge

In each case, Indigenous astronomical knowledge was used to predict changing seasons and the availability of food sources. Behind each of these brief accounts is a complex oral tradition that denotes a moral charter and informs sacred law.

An important thing to consider is that small changes in star positions due to stellar proper motion (rate of angular change in position over time) and precession (change in the orientation of Earth’s rotational axis) means that a few thousand years ago, these sky/season relationships would have been out of sync.

This means knowledge systems had to evolve over time to accommodate a changing sky. This shows us that what we know about Indigenous astronomical knowledge today is only a tiny fraction of the total knowledge developed in Australia over the past 50,000-plus years.

Moving forward

As we increase our understanding of Indigenous knowledge systems, we see that Indigenous people did develop a form of science, which is used by Indigenous and non-Indigenous people today.

Students in Albury/Wodonga learning about Indigenous astronomy through the Charcoal Nights initiative. Murray Arts

Traditional fire practices are used across the country, bush medicines are being used to treat disease, and astronomical knowledge is revealing an intellectual complexity in Indigenous traditions that has gone largely unrecognised.

It is time we show our appreciation for Indigenous knowledge and celebrate the many ways we can all learn from this vast accumulation of traditional wisdom.

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Biodiversity and food security in our future - YouTube

Biodiversity and food security in our future - YouTube | Communicating Science | Scoop.it

In the lead-up to Science in the Pub and WOMADelaide Planet Talks, we talked with Peter Langridge and Jodie Pain about biodiversity and food security in our future.

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A great example of a series of short, linked, talking head videos

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Increased efficiency and safety: what's new for Formula 1

Increased efficiency and safety: what's new for Formula 1 | Communicating Science | Scoop.it
The Formula 1 season begins in Melbourne this week and a number of changes have been made following the tragic accident last year which has left one driver still in a coma.

 

The 66th Formula 1 season is about to get underway this week at Albert Park, in Melbourne, and a number of changes have been introduced this year.

This follows the massive overhaul that took place last year – with certain aspects proving to be quite challenging already.

The FIA (Fédération Internationale de l'Automobile), which is the governing body for Formula 1, has further tightened the rules to make sure manufacturers and drivers are being pushed to increase the efficiency of their cars.

Current regulations state that F1 cars are limited to 1.6-litre turbocharged V6 engines, with a limit of 15,000 RPM (revolution per minute), a maximum fuel flow of 100kg per hour, and a maximum of 100kg fuel carried by the car.

This year, the FIA has reduced the number of allowed power units (engines) for the season from five to four, meaning each power unit will have to cover five races on average, as opposed to four last year. This will put added pressure on each team’s engineers to ensure power units run efficiency and reliability.

Furthermore, the minimum weight of the car has been increased from 691kg to 702kg for the car. This will result in more protective casing for the cars, and will also prevent teams from taking extraordinary steps to reach minimum weight.

Last year, Sauber driver Adrian Sutil was reportedly going on extreme diets prior to races in attempt to shed weight.

Fixing the ‘ugly’ nose

Last year, the nose height was substantially reduced (from 550mm to 185mm), mainly for safety purposes to prevent cars launching upwards in case they rear-end a racing car in front.

But this also resulted in F1 car noses being deemed aesthetically unattractive.

Formula 1 cars, such as this from Mercedes, this year will feature a lower nose than last year. Flickr/Ferran BCN, CC BY-NC-SA

Click to enlarge

Noses will be lower than in 2015 but must feature a taper, be symmetrical and consistent with the centreline of the car.

The newly mandated nose section results in a reduction of downforce at the front of the car. Hence, the main challenge for F1 engineers will be to compensate for the aerodynamic impact of the new nose design.

Virtual Safety Car system

Following Jules Bianchi’s terrible accident in last year’s Japanese Grand Prix – he’s still in a coma after his car crashed into a crane during a double yellow flag situation – a Virtual Safety Car (VSC) will be used when a section of track is under double waved yellow flags (meaning drivers or officials may be in danger).

The idea behind the VSC system is to impose a speed limit to slow down cars during dangerous situations on the track, hence controlling the pack without deploying the actual safety car.

Once the virtual safety car has been called, all electronic marshal panels around the track will display ‘VSC’, while teams will be notified via the official messaging system.

Drivers will not be allowed to enter the pits, unless changing tyres, and must stay above the minimum time set by the FIA at least once in each marshalling sector. Cars may not be driven “unnecessarily slowly, erratically or in a manner which could be deemed potentially dangerous,” with those who fail to stay above the minimum time to be sanctioned by the stewards.

The VSC will be used when “the circumstances are not such as to warrant use of the safety car itself”, according to FIA rules.

The FIA has expanded the use of anti-intrusion panels to protect drivers in the event of a side impact. Also, drivers will not be able to significantly change helmet designs during the course of the season in order for drivers to be easily distinguished from one another.

The appeal of F1 racing

As noted by The Conversation’s contributor Simon Chadwick, while viewership of F1 races has dropped in recent years, F1 remains a seductive proposition for car manufacturers.

F1 racing (and its rules) tend to be part of a larger shift in the automotive industry. Formula 1 is once again placing itself at the forefront of innovation in efficiency and engine design that could trickle down to commercial cars.

While Volkswagen has decided to put off coming back to F1 for now, Honda is returning as an engine supplier in partnership with McLaren.

Gates open at Albert Park this Thursday but actual Formula 1 racing doesn’t begin until Saturday with the qualifying rounds and the actual race on Sunday.

For a little taste of F1 racing before the weekend, watch Australian Daniel Ricciardo take a look at the season ahead as part of the Red Bull team.

The Science & Education team's insight:

For the revheads this weekend

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Pi Day: A once in a century celebration

Pi Day: A once in a century celebration | Communicating Science | Scoop.it
A special Pi Day this year for those who celebrate this remarkable number on March 14, a date that can be written 3/14. Given 3.14 is Pi to two decimal places, what happens when you add in the year?

 

Pi Day – on March 14 – will be particularly memorable this year: the date can be written 3/14 by those who opt for the month then day format, which is Pi to two decimal places, 3.14. If you include the year this year then that gives 3/14/15, which is Pi to four decimal places, 3.1415.

This happens only once a century, and the Museum of Mathematics in New York City, among others, is taking Pi Day 2015 one step further, by celebrating at 9:26pm, adding three more digits to Pi, 3.1415926.

You can personally celebrate the event 12 hours earlier at 9.26am, wait a further 53 seconds to get 3.141592653 Pi to nine decimal places. That’s probably the best time and date approximation to Pi you can get with your typical time piece, although the digits of Pi continue on indefinitely, but more on that later.

Chicagoans plan to celebrate Pi Day this year by running in a Pi-K race of 3.14 miles. Numerous city bakeries are offering special pies for the occasion at US$3.14 per slice.

Another celebration

Not as well known perhaps is the fact that March 14 this year is also the 136th birthday of physicist Albert Einstein, and that 2015 is the 100th anniversary of the publication of Einstein’s paper on general relativity.

To commemorate this doubly significant event, Princeton University is planning a its usual gala event, including a pie eating contest, a performance by the Princeton Symphony, a contest to see who can recite the most correct digits of Pi (the current Guinness world record is 67,890 places), a guided Einstein tour and even an Einstein look-a-like contest.

Young entrants in an Einstein look-a-like competition as Princeton celebration Albert Einstein’s birthday, which coincides with Pi Day. Flickr/Princeton Public Library, CC BY-NC

Click to enlargePi in the popular culture

Pi Day long ago extended its reach beyond a handful of mathematical zealots, to become a widely celebrated, even the subject of a resolution to mark the day each year that was passed by the US House of Representatives in 2009.

This may well be the first legislation on Pi Day to have been adopted by a national governmental body. Pi Day even has its own following on Twitter through the hashtag #piday.

In general, Pi is much more in the public eye than it was even five or ten years ago, as we wrote last year.

Pi continues to fascinate and made another appearance on the US quiz show Jeopardy! on May 9, 2013 when it featured in an entire category of questions. The clues provided were:

(US$200) Pi is the ratio of this measurement of a circle to its diameter.(US$400) Numerically, pi is considered this, like a type of “meditation”.(US$600) For about $19,100 x pi, this “Black Swan” director made “Pi”, his 1998 debut film about a math whiz.(US$800) In the 100s AD this Alexandrian astronomer calculated a more precise value of pi, the equivalent of 3.14166.(US$1,000) You can find the area of this oval geometric shape with pi x A x B, if A & B are half of its longest & shortest diameter.

The clues and the answers (all were answered correctly by various contestants) are given here in the J-archive, an independent repository of clues and answers maintained by Jeopardy! fans.

Current record for computing Pi

Ever since the dawn of the computing age, researchers have plied their craft at computing Pi, by a variety of often exotic techniques.

As we explained earlier, if we count things to the second, this year’s Pi Day gives the number down to nine decimal places, at 3.141592653. But this is still only an approximation to the true value of Pi.

Pi is a transcendental number which means you can continue to expand the number of decimal places of Pi forever and there is no repetitive pattern.

The current record for calculating digits of Pi is 13.3 trillion decimal digits, which has been ascribed to someone known only as “houlouonchi” and Alexander J Yee.

What is Pi good for?

So what is Pi good for, anyway? Does Pi or the digits of Pi ever really enter the day-to-day world? It does, actually, quite a bit.

For example, Pi is central to digital signal processing, which is pervasive in our modern wireless world. The digits of Pi (in binary) are probably somewhere in the programming of your smartphone, used in digitally decoding multichannel, gigahertz signals while you casually chat with your friend about the local weather and politics.

Mathematically speaking, your smartphone is performing a fast Fourier transform, which involves Pi.

Pi even appears in the field equations of Einstein’s general relativity. So when you read reports about tests of Einstein’s general relativity, such as the recent dramatic discovery of a four-way gravitational lens, keep in mind that Pi is behind the equations governing these mind-blowing phenomena.

For those interested in looking over some of the original technical papers on Pi that have appeared over the past 120 years in the American Mathematical Monthly, see the Pi Day anthology by one of us and Scott Chapman in the March 2015 Monthly. While many of these articles are targeted to mathematical researchers, quite a few are readable by those with relatively modest mathematical training.

For the rest of us, perhaps it is enough just to know – for this year’s Pi Day purposes – that Pi = 3.141592653 so set your alarm cocks now for 9:26am, Saturday March 14, 2015, in your favourite timezone, and enjoy the 53 second countdown.

The Science & Education team's insight:

I will be baking tomorrow

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Mapping to make better decisions and improve communication

Mapping  to make better decisions and improve communication | Communicating Science | Scoop.it
Sometimes a different perspective can help you see a problem with fresh eyes. The problem to be solved in Gainesville, Fla.? A hot spot of poverty, child abuse and neglect.

The University of Florida's Dr. Nancy Hardt has an unusual double specialty: She's both a pathologist and an OB-GYN. For the first half of her career, she brought babies into the world. Then she switched — to doing autopsies on people after they die.

"I want to prevent what I'm seeing on the autopsy table. ... A lot of times, I'm standing there going, 'I don't think this person had a very nice early childhood.' "

- Dr. Nancy Hardt, pathologist, University of Florida

It makes perfect sense to her.

"Birth, and death. It's the life course," Hardt explains.

A few years ago, Hardt says, she learned about some research that changed her view of how exactly that life course — health or illness — unfolds.

The research shows that kids who have tough childhoods — because of poverty, abuse, neglect or witnessing domestic violence, for instance — are actually more likely to be sick when they grow up. They're more likely to get diseases like asthma, diabetes and heart disease. And they tend to have shorter lives than people who haven't experienced those difficult events as kids.

"I want to prevent what I'm seeing on the autopsy table," Hardt says. "I've got to say, a lot of times, I'm standing there, going, 'I don't think this person had a very nice early childhood.' "

Back in 2008, Hardt was obsessing about this problem. She wanted to do something to intervene in the lives of vulnerable kids on a large scale, not just patient by patient.

Hardt's Map Of Medicaid Births

The deep blue and red spot on the left shows the Gainesville area's most dense concentration of babies born into poverty — to parents on Medicaid.

Credit: Courtesy of Dr. Nancy Hardt

So, by looking at Medicaid records, she made a map that showed exactly where Gainesville children were born into poverty. Block by block.

Right away she noticed something that surprised her: In the previous few years, in a 1-square-mile area in southwest Gainesville, as many as 450 babies were born to parents living below the poverty line.

It just didn't make sense to her — that was an area she thought was all fancy developments and mansions.

So Hardt took her map of Gainesville, with the poverty "hotspot" marked in deep blue, and started showing it to people. She'd ask them, "What is this place? What's going on over there?"

Eventually she brought the map to the CEO of her hospital, who told her she just had to show it to Alachua County's sheriff, Sadie Darnell.

So Hardt did.

And, to Hardt's surprise, Sheriff Darnell had a very interesting map of her own.

 

Darnell had a thermal map of high crime incidence. It showed that the highest concentration of crime in Gainesville was in a square-mile area that exactly overlaid Hardt's poverty map.

"It was an amazing, 'Aha' moment," says Darnell.

"We kind of blinked at each other," Hardt says. "And — simultaneously — we said, 'We've got to do something.' "

The hotspot is dotted with isolated, crowded apartment complexes with names like Majestic Oaks and Holly Heights. The first time she visited, on a ride-along with Sheriff Darnell's deputies, Hardt tallied up all things that make it hard for kids here to grow up healthy.

Dr. Nancy Hardt's free "clinic on wheels," parked in December at an apartment complex in Gainesville, Fla., gets about 5,000 visits from patients each year.

Bryan Thomas for NPR

There's a lot of poorly maintained subsidized housing. Tarps cover leaky roofs. Mold and mildew spread across stucco walls. Sherry French, a sergeant from the sheriff's office, says lots of families here have trouble getting enough to eat.

Hardt added hunger to her list and substandard housing. And she noticed something else: almost a total lack of services, including medical care.

She mapped it out and determined that the closest place to get routine medical care if you're uninsured — which many people here are — is the county health department. It's almost a two-hour trip away by bus. Each way.

This was a problem a doctor like Hardt could tackle. She would bring medical care to the hotspot, by rustling up a very large donation: a converted Bluebird school bus, with two exam rooms inside.

Hardt organized a massive crew of volunteer doctors and medical students from the University of Florida, where she teaches, and raised the money to hire a driver and a full-time nurse.

The "clinic on wheels" first made it out to the hotspot in 2010, parking right inside one apartment complex there. Patients could walk in without an appointment and get treatment free of charge, approximating the experience of a house call. Today, the mobile clinic gets an average of 5,000 visits from patients per year, in under-served areas all over Gainesville.

Physician assistants and undergraduate care coordinators treat patients in the mobile clinic parked at Majestic Oaks, a low-income apartment complex in Gainesville.

Bryan Thomas for NPR

But the clinic is really just one piece of the puzzle.

Because after the day that Hardt and the sheriff matched up their maps, they kept digging into the data. And, a few years later, Hardt made some new maps. They showed that the crime in the hotspot included the highest concentration of domestic violence, child abuse and neglect in Gainesville.

Childhood Trauma Maps

The reddish pink spots on these maps of the Gaineseville area, indicate an increased density of reports of child abuse and neglect (top map) and domestic violence (bottom). Deep blue indicates the highest concentration.

Source: (Top) Alachua County Department of Children and Families; (Bottom) Gainesville Police Department, Alachua County Sheriff's Office

Credit: Courtesy of Dr. Nancy Hardt

That revelation brought Dr. Hardt back to her original mission — to head off bad health outcomes in the most vulnerable kids. So she teamed up with Sheriff Darnell and other local groups and grass-roots organizers from the neighborhood. They collaborated to create the SWAG (Southwest Advocacy Group) Family Resource Center, right in the Linton Oaks apartment complex.

The SWAG Center opened in 2012. Kids can come play all day long. There's a food pantry, free meals, a computer room, AA meetings. A permanent health clinic is slated to open up across the street next week.

All the resources here are designed to decrease the likelihood of abuse and neglect by strengthening families.

"I think we knew it intuitively — that health issues are associated with crime, [and] crime is associated with health issues and poverty," Darnell says. "But seeing that direct connection literally on a map ... it helped to break down a lot of walls."

Child abuse and domestic violence are still serious problems, but there has been a small drop in the numbers of such calls over the past few years, according to the data.

Hardt says that investing in families and health now can help kids grow up healthy — and save money in the future.

"Conservatives or liberals, everybody gets that," she says. "That we have limited resources and we need to really spend them wisely. I think the maps — the hot spot maps — just tell us policywise, where we need to be going and what we need to be doing."

Hardt's next goal is to make more people aware of the links between health and early education. Last summer, the county got a new superintendent of schools. Hardt has been to visit him three times already — maps in hand.

The Science & Education team's insight:

How maps (as one form of representation) allow a more acute form of analysis and communication.

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Oldest known sponge pushes back date for key split in animal evolution

Oldest known sponge pushes back date for key split in animal evolution | Communicating Science | Scoop.it
Oldest known sponge pushes back date for key split in animal evolution

 

To the untrained eye, real animal sponges may seem as boring as synthetic kitchen sponges. But the evolution of these highly porous creatures has long been a mystery, with major implications for the early evolution of animals. Scientists debate when sponges, animals belonging to the phylum Porifera, first emerged. Some think it wasn’t until the Cambrian period, between 541 million and 485 million years ago, whereas others put it as early as 760 million years ago, during Precambrian times. Yet while some genetic analyses of modern sponges suggest a Precambrian date, claims for fossils that early have been met with skepticism due to their poor preservation. Getting the date right is important for understanding the timing and course of animal evolution, because the split between the sponges and most other animals (called the Eumetazoa) was a key event in the early history of life on Earth. A research team now claims that the tiny fossil pictured above, discovered in southern China and dated to 600 million years ago—clearly during the Precambrian—is the oldest known poriferan. The critter, reported online today in the Proceedings of the National Academy of Sciences, is just over 1 millimeter high and wide, the size of a small bead, and was found in a phosphorus-rich geological formation known for preserving animal fossils in an excellent state. The new specimen, the team says, is unmistakably spongelike, featuring three hollow tubes and a highly porous surface. The new discovery indicates that the common ancestor of sponges and Eumetazoa lived much earlier than many scientists assumed. And because today’s sponges and eumetazoans differ in some important genetic features, the team says, the find could also help date the first appearance of genes key to the evolution of most animals living today.

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Dark energy and dark matter: An introduction

Dark energy and dark matter: An introduction | Communicating Science | Scoop.it
Prev | Table of Contents | Next Leave a comment (0) Science 6 March 2015:
Vol. 347 no. 6226 pp. 1100-1102
DOI: 10.1126/science.aaa0980 ReviewThe dark side of cosmology: Dark matter and dark energyDavid N. Spergel*

+ Author Affiliations

Princeton University, Princeton, NJ 08544, USA.↵*Corresponding author. E-mail: dns@astro.princeton.eduAbstract

A simple model with only six parameters (the age of the universe, the density of atoms, the density of matter, the amplitude of the initial fluctuations, the scale dependence of this amplitude, and the epoch of first star formation) fits all of our cosmological data . Although simple, this standard model is strange. The model implies that most of the matter in our Galaxy is in the form of “dark matter,” a new type of particle not yet detected in the laboratory, and most of the energy in the universe is in the form of “dark energy,” energy associated with empty space. Both dark matter and dark energy require extensions to our current understanding of particle physics or point toward a breakdown of general relativity on cosmological scales.

Related ResourcesIn Science MagazineIntroduction to Special Issue Einstein's vision Margaret Moerchen, Robert CoontzScience 6 March 2015: 1082-1083.

John Archibald Wheeler, my academic great-grandfather, succintly summarized “geometrodynamics,” his preferred name for the theory of general relativity (1): “Spacetime tells matter how to move; matter tells spacetime how to curve.”

Cosmologists observe the motion of atoms (either in the form of gas or stars) or follow the paths taken by light propagating across the universe and use these observations to infer the curvature of spacetime. They then use these measurements of the curvature of spacetime to infer the distribution of matter and energy in the universe. Throughout this Review I will discuss a variety of observational techniques, but ultimately they all use general relativity to interpret the observations and they all lead to the conclusion that atoms, stuff that we understand, make up only 5% of the matter and energy density of the universe.

Standard cosmological model fits, but at a price

Observations of the large-scale distribution of galaxies and quasars show that the universe is nearly uniform on its largest scales (2) and that the velocity of a distant galaxy depends on its distance (3). General relativity then implies that we live in an expanding universe that started in a big bang. Because the universe expands, light is “redshifted,” so that light from a distant galaxy appears redder when it reaches us. Hubble’s observations that found a linear relationship between galaxy redshift and distance established the basic model in the 1920s.

Our current cosmological standard model assumes that general relativity and the standard model of particle physics have been a good description of the basic physics of the universe throughout its history. It assumes that the large-scale geometry of the universe is flat: The total energy of the universe is zero. This implies that Euclidean geometry, the mathematics taught to most of us in middle school, is valid on the scale of the universe. Although the geometry of the universe is simple, its composition is strange: The universe is composed not just of atoms (mostly hydrogen and helium), but also dark matter and dark energy.

The currently most popular cosmological model posits that soon after the big bang, the universe underwent a period of very rapid expansion. During this inflationary epoch, our visible universe expanded in volume by at least 180 e-foldings. The cosmic background radiation is the leftover heat from this rapid expansion. This inflationary expansion also amplifies tiny quantum fluctuations into variations in density. The inflationary model predicts that these fluctuations are “nearly scale-invariant”: The fluctuations have nearly the same amplitude on all scales.

These density variations set off sound waves that propagate through the universe and leave an imprint in the microwave sky and the large-scale distribution of galaxies. Our observations of the microwave background are a window into the universe 380,000 years after the big bang. During this epoch, electron and protons combined to form hydrogen. Once the universe became neutral, microwave background photons could propagate freely, so the sound waves imprint a characteristic scale, the distance that they can propagate in 380,000 years. This characteristic scale, the “baryon acoustic scale,” serves as a cosmic ruler for measuring the geometry of space, thus determining the density of the universe.

Observations of the temperature and polarization fluctuations in the cosmic microwave background, both from space (4–6) and from ground-based telescopes (7, 8), test this standard cosmological model and determine its basic parameters. Remarkably, a model with only six independent parameters—the age of the universe, the density of atoms, the density of matter, the amplitude of the density fluctuations, their scale dependence, and the epoch of first star formation—provides a detailed fit to all of the statistical properties of the current microwave background measurements. The same model also fits observations of the large-scale distribution of galaxies (9), measurements of the Hubble constant, and the expansion rate of the universe (10, 11), as well as distance determinations from supernovae (12). The success comes at a price: Atoms make up less than 5% of our universe; the standard model posits that dark matter dominates the mass of galaxies and that dark energy, energy associated with empty space, makes up most of the energy density of the universe (see Fig. 1).

View larger version:In this pageIn a new windowDownload PowerPoint Slide for TeachingFig. 1 The multiple components that compose our universe.

Dark energy comprises 69% of the mass energy density of the universe, dark matter comprises 25%, and “ordinary” atomic matter makes up 5%. There are other observable subdominant components: Three different types of neutrinos comprise at least 0.1%, the cosmic background radiation makes up 0.01%, and black holes comprise at least 0.005%.

Astronomical observations and cosmological theory suggest that the composition of the universe is remarkably rich and complex. As Fig. 1 shows, the current best estimates of the universe’s composition (5–8) suggest that dark energy, dark matter, atoms, three different types of neutrinos, and photons all make an observable contribution to the energy density of the universe. Although black holes are an unlikely candidate for the dark matter (13), their contribution to the mass density of the universe is roughly 0.5% of the stellar density (14).

Astronomical evidence for dark matter

The evidence for dark matter long predates our observations of the microwave background, supernova observations, and measurements of large-scale structure. In a prescient article published in 1933, Fritz Zwicky (15) showed that the velocities of galaxies in the Coma cluster were much higher than expected from previous estimates of galaxy masses, thus implying that there was a great deal of additional mass in the cluster. In the 1950s, Kahn and Woltjer (16) argued that the Local Group of galaxies could be dynamically stable only if it contained appreciable amounts of unseen matter. By the 1970s, astronomers argued that mass in both clusters (17) and galaxies (18) increased with radius and did not trace light. Theoretical arguments that showed that disk stability required dark matter halos (19) buttressed these arguments. Astronomers studying the motion of gas in the outer regions of galaxies found evidence in an ever-increasing number of systems for the existence of massive halos (20–24). By the 1980s, dark matter had become an accepted part of the cosmological paradigm.

What do we know about dark matter from astronomical observations today?

Microwave background and large-scale structure observations imply that dark matter is five times more abundant than ordinary atoms (4–8). The observations also imply that the dark matter has very weak (or no) interactions with photons, electrons, and protons. If the dark matter was made of atoms today, then in the early universe, it would have been made of ions and electrons and would have left a clear imprint on the microwave sky. Thus, dark matter must be nonbaryonic and “dark.”

Observations of large-scale structure and simulations of galaxy formation imply that the dark matter must also be “cold”: The dark matter particles must be able to cluster on small scales. Simulations of structure formation with cold dark matter (and dark energy) are generally successful at reproducing the observations of the large-scale distribution of galaxies (25). When combined with hydrodynamical simulations that model the effects of cooling and star formation, the simulations can reproduce the basic observed properties of galaxies (26, 27).

Supermassive clusters are important laboratories for studying dark matter properties. These clusters are thought to be “fair samples” of the universe, as the ratio of dark matter to ordinary matter observed in the clusters is very close to the cosmological value (28). X-ray observations directly trace the distribution of ordinary (“baryonic”) matter as most of the atoms in the cluster gas have been ionized. As Zwicky (29) first discussed, observations of gravitational lensing of background galaxies directly trace the total distribution of matter in the clusters. Today, over 75 years after Zwicky’s suggestion, astronomers use large-format cameras on the Hubble Space Telescope to make detailed maps of the cluster dark matter distribution (30). These observations reveal considerable amounts of dark matter substructure in the clusters, generally consistent with the predictions of numerical simulations (31).

At much smaller scales, dwarf galaxies are another important astronomical testing ground for theories of dark matter. The gravitational potential wells of these dark matter–dominated systems are quite shallow, so the predicted properties of dwarf galaxy halos are quite sensitive to dark matter properties. Several groups (32, 33) have argued that the observed properties of dwarf galaxies do not match the predictions of numerical simulations. Although some astrophysicists argue that improved models of star-formation feedback can reconcile this discrepancy (34), others suggest that dark matter self-interactions are needed to match simulations to observations (35).

All of the astronomical arguments for the existence of dark matter assume that general relativity is valid on galactic scales. Alternative gravity theories, such as modified Newtonian dynamics (MOND) (36), obviate the need for dark matter by changing the physics of gravity. Although these models have some phenomenological success on the galaxy scale (37), they have great difficulties fitting the microwave background fluctuation observations (4–8, 38) and observations of clusters, particularly the bullet cluster (39). Most theorists also consider these alternative models as lacking motivation from fundamental physics.

What is the dark matter?

The existence of nonbaryonic dark matter implies that there must be new physics beyond the standard model of particle physics. Particle physicists have suggested a wealth of possibilities, some motivated by ideas in fundamental physics and others by a desire to explain astronomical phenomena (40).

The early universe was an incredibly powerful particle accelerator. At the high temperatures and densities of the early moments of the big bang, the cosmic background radiation created an enormous number of particles. Cosmic microwave background experiments (5–8) have detected the observational signatures of the copious number of neutrinos produced in the early first moments of the universe. These early moments could have also created the dark matter particles.

Supersymmetry, the most studied extension of our current understanding of particle physics, provides potential candidates for dark matter. Particles can be divided into two types: fermions and bosons. Fermions obey the Pauli exclusion principle: Only one particle can be found in each state. Multiple bosons can be found in the same quantum state. Electrons are fermions, while photons are bosons. Supersymmetry would be a new symmetry of nature that links each boson to a fermionic partner and vice versa. This symmetry implies a plethora of new particles: The photon would have a fermionic partner, the photino, and the electron would have a bosonic partner, the selectron. One of the goals of the Large Hadron Collider (LHC) is to search for these yet undiscovered supersymmetric particles.

The lightest supersymmetric particle (LSP) can be stable. These particles would have been produced copiously in the first moments after the big bang. For certain parameters in the supersymmetric model, the abundance of the LSP is just what is needed to explain the observed abundance of dark matter. This success is an example of the “WIMP miracle” of cosmology: A weakly interacting massive particle (WIMP), a particle that interacts through exchanging particle with masses comparable to the Higgs mass, has the needed properties to be the dark matter.

Particle physics suggests other well-motivated dark matter candidates, including the axion (41) and “asymmetric dark matter” (42), particles whose abundances are not set by their cross section but by an asymmetry between particles and antiparticles.

If WIMPs are the dark matter, then they could be detected through several different routes: Dark matter could be created at an accelerator or seen either in deep underground experiments or through astronomical observations (40, 43). These possibilities have led to an active program of searching for dark matter. This search has had many exciting moments. There are currently a number of intriguing signals that might turn out to be the first detection of dark matter:

1) The Gran Sasso Dark Matter (DAMA) experiment has seen an annual modulation in the event rate in its detector (44) with just the theoretical predicted form (45). The interpretation of this result is controversial, as other experiments have failed to detect dark matter and seem to be in contradiction with this detection claim (46, 47).

2) There have been multiple claims of excess gamma-ray signals coming from the center of our Galaxy at a range of potential dark matter masses (48, 49). Because of the high dark matter density in the galactic center, it is potentially the brightest source of high-energy photons produced through dark matter self-annihilation. However, the galactic center also contains a wealth of astrophysical sources that emit high-energy photons. Searches in external galaxies have also suggested the existence of dark matter with yet a different mass (50). This claim is also controversial (51). Cosmologists hope that observations of nearby dwarfs could provide a less ambiguous signal (52).

3) Dark matter annihilation in our Galaxy could potentially produce positrons. Cosmic-ray experiments have been searching for these signals (53). The challenge for these experiments is to separate this signal from astrophysical sources of cosmic rays, such as pulsars and production from secondary collisions.

Hopefully, future experiments will verify one of these results.

The discovery of the dark matter particle would resolve a long-standing mystery in astronomy, provide insights into dark matter’s role in galaxy formation and structure, and be the first signature of new physics beyond the Higgs.

Dark energy

When Einstein introduced his theory of general relativity, he added a cosmological constant term. This term generated a repulsive force that countered the pull of gravity and kept the universe static and stable. In the 1920s, Hubble’s discoveries showed that the universe was expanding, and physicists dropped the cosmological constant term.

Motivated by observational evidence favoring a low-density universe and theoretical prejudice that favored a flat universe, enthusiasm for a cosmological constant revived in the 1970s and 1980s in the astronomy community (54–56). Physicists recognized that the value of the cosmological constant was a profound problem in fundamental physics (57).

A universe dominated by a cosmological constant is a strange place to live. We think of gravity as an attractive force. If you throw a ball upwards, gravity slows its climb out of the Earth’s gravitational well. Similarly, gravity (in the absence of a cosmological constant) slows the expansion rate of the universe. Imagine your surprise if you threw a ball upwards and it started to accelerate! This is the effect that a cosmological constant has on the universe’s rate of expansion.

Supernova observations provided critical evidence for the universe’s acceleration. Supernovae are bright stellar explosions of nearly uniform peak luminosities (58). Thus, they serve as beacons that can be used to determine the light-travel distance to their host galaxies. By determining distance as a function of galaxy redshift, the supernova observations measure the expansion rate of the universe as a function of time. In the late 1990s, supernova observers reported the surprising result that the expansion rate of the universe is accelerating (59, 60).

Over the past 15 years, the observational evidence for cosmic acceleration has continued to grow. Measurements of the baryon acoustic scale, both in the microwave background (3–8) and in the galaxy distribution (9) as a function of redshift, traced the scale of the universe back to a redshift of 1100. Measurements of the growth rate of structure as a function of redshift also reinforced the case for cosmic acceleration.

Why is the universe accelerating? The most studied possibility is that the cosmological constant (or equivalently, the vacuum energy of empty space) is driving cosmic acceleration. Another possibility is that there is an evolving scalar field that fills space (like the Higgs field or the inflaton field that drove the rapid early expansion of the universe) (61). Both of these possibilities are lumped together in “dark energy.” Because all of the evidence for dark energy uses the equations of general relativity to interpret our observations of the universe’s expansion and evolution, an alternative conclusion is that a new theory of gravity is needed to explain the observations (38). Possibilities include modified gravity theories with extra dimensions (62).

Future observations can determine the source of cosmic acceleration and determine the nature of dark energy. Our observations can measure two different effects: the relationship between distance and redshift and the growth rate of structure (63). If general relativity is valid on cosmological scales, then these two measurements should be consistent. These measurements will also determine the basic properties of the dark energy.

Astrophysicists are currently operating several ambitious experiments that aim to use measurements of galaxy clustering and supernova observations to measure distance and gravitational lensing observations to measure the growth rate of structure (64, 65, 66). These are complemented by microwave background observations (67, 68, 69) that will provide independent measurements of gravitational lensing and more precise measurements of cosmic structure. In the next decade, even more powerful observations will map the large-scale structure of the universe over the past 10 billion years and trace the distribution of matter over much of the observable sky background (70, 71, 72). These observations will provide deeper insights into the source of cosmic acceleration.

Conclusions

Although general relativity is now a hundred-year-old theory, it remains a powerful, and controversial, idea in cosmology. It is one of the basic assumptions behind our current cosmological model: a model that is both very successful in matching observations, but implies the existence of both dark matter and dark energy. These signify that our understanding of physics is incomplete. We will likely need a new idea as profound as general relativity to explain these mysteries and require more powerful observations and experiments to light the path toward our new insights.

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Homo erectus older than we thought

Homo erectus older than we thought | Communicating Science | Scoop.it
Deep roots for the genus HomoAnn Gibbons 

On a hot January morning 2 years ago, Chalachew Seyoum was searching for fossils at a desolate site in Ethiopia called Ledi-Geraru, where no human ancestor had turned up in a decade of searching. But Seyoum, an Ethiopian graduate student at Arizona State University (ASU), Tempe, was upbeat after a week off. “I had a lot of energy and fresh eyes,” he says. “I was running here and there. I went up a little plateau and over the top when I spotted this specimen popping right out.”

He sat down and closed his eyes. When he opened them, he could more clearly see the gray fossil poking out of the bleached sand and mudstone, and he realized that he had found the jawbone of a hominin—a member of the human family. He called out for the ASU expedition leader: “Kaye Reeeed!” Reed scrambled up the steep slope on her hands and knees, saw the fossil, and yelled “Woo-hoo!”

Their excitement was justified. In two papers online this week in Science (http://scim.ag/BVillmoare; http://scim.ag/ENDiMaggio), the ASU team and co-authors introduce the partial lower jaw as the oldest known member of the genus Homo. Radiometrically dated to almost 2.8 million years ago, the jaw is a window on the mysterious time when our genus emerged. With both primitive and more modern traits, it is a bridge between our genus and its ancestors and points to when and where that evolutionary transition took place. As a transitional form “it fits the bill perfectly,” says paleontologist Fred Spoor of University College London.

Together with a reassessment of known fossils, published in Nature this week by Spoor and colleagues, the find is stimulating new efforts to sort out the mixed bag of early Homo remains and to work out which forms emerged first. “This causes us to rethink early Homo,” says paleoanthropologist Bernard Wood of George Washington University in Washington, D.C.

 

This partial lower jaw from Ethiopia is the oldest example of our genus Homo.

CREDIT: KAYE REED

Researchers agree that small-brained hominins in the genus Australopithecus evolved into early Homo between 3 million and 2.5 million years ago, but the Homo fossil trail disappears at the crucial time. Until now, the oldest known Homo fossil was a 2.3-million-year-old upper jaw from Hadar, Ethiopia, that has not been classified into a species. It and other early Homo fossils paint a confusing picture. Some have big skulls, others small; some consist of a bit of skull, others only a jaw, resulting in a grab bag of mismatched parts. As a result, researchers have argued about whether there was a single species of early Homo or three. The type specimen of H. habilis, for example, includes a 1.8-million-year-old lower jaw called OH 7 from Olduvai Gorge in Tanzania (Science, 17 June 2011, p. 1370). But the type specimen of another species, H. rudolfensis, is a 2.1-million-year-old skull without teeth or a lower jaw.

This week's papers advance the work on two fronts. Spoor and colleagues created a virtual reconstruction of the OH 7 specimen, which was found 55 years ago, to correct for postmortem distortion. They used computed tomography and 3D imaging to digitize and reassemble pieces of the jaw in the computer. Then they compared OH 7 with other specimens and found that it has more primitive features, such as a long, narrow palate, than do the older Hadar jawbone and members of H. rudolfensis. Although OH 7 itself is relatively recent, their analysis suggested that H. habilis arose earlier than the other two species.

 Homeland for Homo

The oldest known fossil of our genus comes from an evolutionary hotspot in Ethiopia, a place already known as the home of Australopithecus afarensis (Lucy's species); the oldest stone tools; and younger Homo specimens.

Meanwhile, the ASU team spent years doing targeted searches for an older ancestor. They hunted in sediments that were the right age—2.58 million to 2.84 million years old—and in an epicenter of early human evolution. Ledi-Geraru is only 30 kilometers from Hadar, home of the 2.3-million-year-old Homo jaw, as well as to more than 100 individuals of Australopithecus afarensis, the species of the famous skeleton called Lucy. The oldest known stone tools, dated to 2.6 million years ago, are only 40 km away at Gona.

The new Ledi-Geraru discovery fits best in Homo, says ASU paleoanthropologist William Kimbel. Its molars are slimmer than those of Australopithecus, the third molar is smaller, and the jawbone is shaped differently. The ASU team hasn't assigned the jaw to a species yet because they hope to find more parts, but say that it most closely resembles H. habilis.

In fact, the new jaw looks a lot like what Spoor imagined for the ancestor of OH 7. That suggests that although the two specimens are separated by almost 1 million years, they belong to the same lineage, and that the oldest Homo looked most like H. habilis, just as Spoor and others have predicted.

But the Ledi-Geraru specimen is not likely to be a member of H. habilis itself, Spoor says. The jaw also has traits that link it with A. afarensis, such as a rounded chin region. The similarities strengthen the proposal that Lucy's species, which lived from 2.95 million to 3.8 million years ago, was the direct ancestor of Homo. But other types of australopiths also lived during that time, making the genealogy exercise premature.

The ASU team does rule out A. sediba from South Africa as the Homo ancestor, because at 1.9 million years old it is too recent. But its discoverer, paleoanthropologist Lee Berger of the University of the Witwatersrand in Johannesburg, South Africa, says that the known A. sediba skeletons might simply be late examples of the species.

The new data may help solve a puzzle: Why did so many kinds of hominins roam East Africa between 2 million and 3 million years ago? To understand this burst of evolution, the ASU team analyzed the bones of other species living at that time. As they report in the second Science paper, fully one-third of the Ledi-Geraru mammals were new species, not seen in older sediments at nearby Hadar.

Three million years ago, Hadar was home to monkeys, giraffes, and elephants that favored a patchwork of woods and grasslands. Ledi-Geraru hosted a different fauna just 200,000 years later, with grazers such as gazelles, zebras, wild pigs, and a baboon at home in open grasslands like the Serengeti. Climate change and the shift to more open terrain may have spurred the emergence of many species, including members of Homo and Australopithecus, Reed says. “This is a snapshot of a hominin in a landscape that's really open,” agrees paleoclimatologist Peter deMenocal of Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York, who has argued that climate change sparked intense periods of speciation.

Researchers often reconstruct ancient climate from clues in sediment cores. To better correlate climate and human evolution, in 2013 researchers cored lakebeds close to key fossil sites (Science, 2 August 2013, p. 474). “Stay tuned,” deMenocal says. “We'll be answering this [climate question] within a year.”

The Science & Education team's insight:

The vision of erectus and australopithecines living together evokes the more recent image of sapiens, neanderthals and denisovians living togehter

 

Listen to Chris Smith explain: http://www.abc.net.au/radionational/programs/breakfast/science-with-chris-smith-earliest-genus-remains/6284808

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Newly discovered moth is enigmatic evolutionary wonder

Newly discovered moth is enigmatic evolutionary wonder | Communicating Science | Scoop.it
Amateurs and experts worked together to unravel the mystery of a new moth, the first discovery of its kind in 40 years.

 

The discovery of a new family of moth is one of the most exciting finds in entomology in the past 40 years. It was found not in some remote and unexplored region of Australia, but right in our backyard on Kangaroo Island in South Australia. The island that is only 100km from Adelaide and 13km from the mainland, that has been settled since 1836 and is one of the loveliest destinations for a holiday.

This family of moths (Aenigmatineidae) contains a single genus (Aenigmatinea) and single species (Aenigmatinea glatzella) which, to date, is found at a single site close to the beach on a single type of native pine tree (Callitris gracilis). Details of the discovery were first published earlier this year in the journal Systematic Entomology.

The moth – whose less technical name is the Enigma moth – is small with wings that are about 4mm long, and looks more like a caddis-fly than a moth. Despite their size they are exceptionally beautiful, with the males golden and females metallic purple.

A specimen of the Engima moth. You Ning Su, CSIRO, Author provided

Click to enlargeWhat’s in a name?

The genus name, Aenigmatinea, (along with its common name) reflects the enigmatic nature of the moth’s morphology. The moth has an odd mixture of physical characters that made it difficult to place within an evolutionary framework: its wings and genitalia showed it to be primitive -– but how primitive?

Richard Glatz hunting the Enigma moth on Kangaroo Island. Janine Mackintosh, Author provided

Click to enlarge

The most primitive moths have jaws, with one of the first steps in the evolution of advanced moths and butterflies being the development of a tongue. Aenigmatinea has neither – its mouth parts are almost entirely reduced.

The solution to the puzzle was to rely on the moth’s DNA and compare its sequence to potential relatives. The answer was intriguing -– the moth’s closest relatives have a tongue and Aenigmatinea has lost its tongue over time.

The “–tinea” part of the generic name refers to the name that Swedish botanist Carl Linnaeus gave small moths when he first created the binomial naming system that we use for all moths and animals.

What about the specific name, “glatzella”? This a little pun of the type that taxonomists often like. The moth’s head is partially bald -– a little male pattern baldness -– and “glatze” is German for “bald head”.

Glatzella also honours the moth’s discoverer Richard Glatz, the South Australian entomologist, who has fallen in love with Kangaroo Island and who for 15 years, in his own time, has documented the island’s insect fauna.

Why the excitement?

Primitive moths, those in which there is a single genital opening in the female, comprise less than 1% of extant lepidopteran species (moths and butterflies), but represent much of its physical diversity. The discovery of a new family of moths tells us about the early steps that led to the evolution of the more typical moths and butterflies, which are more familiar.

Close examination of the tiny Enigma moth. Alan Landford,CSIRO, Author provided

Click to enlarge

Discoveries of new families of anything are a big deal. Families are three rungs from the bottom of the taxonomic ladder -– above genera and species. New species and new genera of moths and butterflies are discovered every week, but it has been 40 years since a new family of primitive moths and butterflies have been discovered anywhere in the world.

The second reason this is exciting is because it highlights what a special place Australia is and what a special responsibility we have to take care of it. In Europe it is a big deal to identify and name a new species of moth; in Australia, we have tens of thousands of new species to name, and untold numbers of species that remain to be discovered.

This picture is duplicated, to a greater or lesser extent, for virtually every insect order. With so much collecting and naming to do before we have a good picture of our insect fauna, how can we possibly make informed decisions about which areas of our environment merit protection.

The discovery

This discovery is also exciting because it highlights the importance of citizen science and the interplay between people working in a private capacity and professional researchers.

The authors on the paper describing the new moth are a miscellany of characters. Richard Glatz is professional entomologist but has a private passion for the insect-life of Kangaroo Island. Andy Young is not professionally trained, but is a superbly gifted field-worker, who also lives on Kangaroo Island, with a great eye for unusual moths.

Richard and Andy were insightful enough to know they had discovered something interesting and generous enough to know they needed additional help to develop the discovery into a paper.

In 2009 they sent the only two moths they had collected to one of us (Ted Edwards, who works in an honorary capacity at the Australian National Insect Collection (ANIC)).

Ted Edwards with some of the collection at the Australian National Insect Collection. Alan Landford, CSIRO, Author provided

Click to enlarge

Realising the moth was unique, we sent it to Denmark to Niels Kristensen, the guru of primitive moth taxonomy, at the University of Copenhagen, who recognised it was a new family of moths.

A team of collectors from Australia and New Zealand, some professional entomologists and some experienced but self-trained amateurs, then joined Richard and Andy on Kangaroo Island to find additional specimens required for production of a scientific paper.

Researchers at the Department of Zoology at the University of Melbourne generated DNA sequences of the moth, which were then analysed in Finland. With these data, the moth was formally described by Niels and Ted and they produce their paper over a six month period, with emails sent back and forth across the world.

The paper was accepted late in 2014, a few weeks before Niels Kristensen passed away, a life tragically cut short with so many projects remaining uncompleted.

Having a major scientific paper produced collaboratively by private individuals and professional scientists is unusual. But surely this is a recipe to repeat and who knows what other insects may be discovered in Australia’s back yard.

The Science & Education team's insight:

The joy of old fashioned biology

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Does high-salt diet combat infections?

Does high-salt diet combat infections? | Communicating Science | Scoop.it
New study in mice shows that hoarding salt in skin may boost the body’s ability to fend off microbes

 

Conventional wisdom holds that consuming too much sodium chloride is bad for you. High-salt diets have been linked to high blood pressure, cardiovascular disease, and even autoimmune disorders. But a new study shows that dietary salt could also have immune-boosting effects. Researchers report that high levels of salt in skin help mice fight off bacteria and that humans may also stockpile salt at infection sites.

“The idea that salt storage might have evolved for host defense is very exciting,” says Gwen Randolph, an immunologist at Washington University in St. Louis who was not involved in the study. “It’s almost so new that it’s hard to swallow. I think it will take some time for the immunology community to allow this concept to take hold.”

Scientists only recently learned that the connective tissue of skin can serve as a reservoir for sodium ions when we consume large amounts of salt. When Jens Titze, a clinical pharmacologist at the Vanderbilt University School of Medicine in Nashville and the study’s principle author, was studying dietary salt intake in mice, he noticed that even mice on low-salt diets had unusually high salt concentrations in wounded skin. Titze and his colleagues realized that immune cells arriving in wounded skin to fight infections were entering a salty microenvironment. They hypothesized that the body was shuffling salt to infected skin to protect against invaders. In other words, “we are salting our cells in order to protect ourselves,” says Jonathan Jantsch, a microbiologist at the University of Regensburg in Germany and first author on the study, which appears in the current issue of Cell Metabolism.

To find out if all that extra sodium chloride was harming or helping immunity, the researchers turned to macrophages, an immune cell that engulfs and digests invading pathogens. Activated macrophages kill off invaders by releasing microbe-slaying molecules called reactive oxygen species, and the team thought high salt concentrations might trigger the immune cells to produce these compounds. The team cultured macrophages from mice and sprinkled salt into the nutrient bath until the cells were growing in a sodium chloride concentration equivalent to what they’d seen in the rodents’ infected skin. Salt increased the microbe-killing capacity of the immune cells, the team reports; the macrophages exposed to high levels of sodium chloride released significantly more microbicidal molecules than those that grew in a culture medium without salt. Next, the team infected macrophages with the common pathogens Escherichia coli or Leishmania major. After 24 hours, the E. coli load in macrophages exposed to high sodium chloride levels was less than half of that of macrophages cultured without salt, and L. major infections were down as well.

To test whether increased salt intake enhances immune defense in living mice, the researchers fed one group of mice a high-salt diet and the other group a low-salt diet for 2 weeks, then infected the skin on the rodents’ footpads with L. major. For the following 20 days, both groups of mice showed significant swelling in their footpads as the infection took hold, regardless of their diet. After that period, however, mice on the high-salt diet showed improved healing with fewer foot lesions and a lower parasite load than the group eating low-salt food.

“[The experiments] demonstrate that extremes of salt intake result in additional salt accumulation in infected skin and boost immune defense experimentally,” Jantsch says.

In humans, the group found evidence that salt accumulation may be localized to sites of infection. Using a new MRI technique that measures sodium in skin, the team found unusually high levels of salt accumulation in bacterial skin infections of people, whether they consumed a high-salt diet.

Taken together, the group’s findings indicate that both mice and humans may be benefiting from a salt-driven boost in immune defense. But don’t start loading more salt on your fries just yet. “The one thing you don’t want to take away from this study is that it authorizes you to eat more salt to enhance immunity,” Randolph says. A high-salt diet may have been a useful way to fight infections in our ancestors, before antibiotics existed or we lived long enough to develop cardiovascular diseases, but today, the detrimental effects of a high-salt diet outweigh any potential immunological benefits, according to Jantsch. Increasing salt concentration in infected skin from outside the body—by loading tissues with salty intravenous fluids, wound gels, or dressings—may be a more realistic potential application of the findings, he says.

Additional research is needed before such treatments are feasible, but the findings “do raise the possibility that this relatively simple mechanism might be able to enhance or promote immunity,” says Thomas Coffman, a nephrologist at Duke University Medical Center in Durham, North Carolina. “It is very provocative from that standpoint.”

The Science & Education team's insight:

Don't start eating more salt but the mechanisms are interesting

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How big is the average penis?

How big is the average penis? | Communicating Science | Scoop.it
Scientists are refining what constitutes "normal"

 

“I was in the pool!” George Costanza’s distress at the “shrinkage” of his penis after exiting a cold pool was hilarious in the 1994 Seinfeld episode, but for many men concern over the length and girth of their reproductive organ is no laughing matter. Now, a new study could assuage such worries with what may be the most accurate penis-size measurements to date.

Many earlier studies relied on self-reporting, which doesn’t always yield reliable results. “People tend to overestimate themselves,” says David Veale, a psychiatrist at the South London and Maudsley NHS Foundation Trust. So when Veale and his team set out to settle the score on penile proportions, they decided to compile data from clinicians who followed a standardized measuring procedure.

Published today in the British Journal of Urology International, their new study synthesizes data from 17 previous academic papers that included measurements from a total of 15,521 men from around the world. The data enabled the researchers to calculate averages and model the estimated distribution of penile dimensions across humanity. “It still just strikes me how many men have questions and insecurities and concerns about their own penis size. We actually do need good data on it,” says Debra Herbenick, a behavioral scientist at Indiana University, Bloomington, who was not involved in the study.

According to the team’s analysis, the average flaccid, pendulous penis is 9.16 cm (3.61 inches) in length; the average erect penis is 13.12 cm (5.16 inches) long. The corresponding girth measurements are 9.31 cm (3.66 inches) for a flaccid penis and 11.66 cm (4.59 inches) for an erect one.

A graph of the size distribution shows that outliers are rare. A 16-cm (6.3-inch) erect penis falls into the 95th percentile: Out of 100 men, only five would have a penis larger than 16 cm. Conversely, an erect penis measuring 10 cm (3.94 inches) falls into the 5th percentile: Only five out of 100 men would have a penis smaller than 10 cm.

Gentlemen, if you’re eager to see how you measure up, you’ll need to follow the same measurement procedure used in the study. All length measurements were made from the pubic bone to the tip of the glans on the top side of the penis. Any fat covering the pubic bone was compressed before measurement, and any additional length provided by foreskin was not counted. Circumference was measured at the base of the penis or around the middle of the shaft, as the two sites were deemed equivalent.

The researchers concluded that there was no strong evidence to link penis size to other physical features such as height, body mass index, or even shoe size. Yes, it seems that the only definite conclusion that can be drawn about a fellow with big socks is that he probably has big feet. Likewise, the study found no significant correlation between genital dimensions and race or ethnicity, although Veale points out that their study was not designed to probe such associations, because much of the data used were from studies of Caucasian men.

It’s easy to laugh at poor George Costanza for his shrunken manhood, but some reports suggest that only about 55% of men are satisfied with their penis size. Some seek potentially dangerous surgical solutions to a problem that, according to Veale, is often only in their head. Men “seem to have a very distorted picture of what [size] other men are, and what they believe they should be,” Veale says.

Pornography, in which male performers are often selected for their extremely large genitalia, may be partly to blame. Similarly, Herbenick points to the myriad spam e-mails that assert that 17.78 cm (7 inches) is average for an erection, when in reality such a member would place its owner in about the 98th percentile. It’s best to just ignore those ads in any case, Veale says. “There are no effective lotions or potions or pills.”

The Science & Education team's insight:

I couldn't resist this item. There are some good messages about normal distributions and humans perceptions of distributions.

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First photographs emerge of new Pacific island off Tonga

First photographs emerge of new Pacific island off Tonga | Communicating Science | Scoop.it
Three men scale peak of new one-mile island off Tonga which is believed to have formed after a volcano exploded underwater and then expanded

 

The first photographs have emerged of a newly formed volcanic island in the Pacific Ocean after three men climbed to the peak of the land mass off the coast of Tonga. Experts believe a volcano exploded underwater and then expanded until an island formed. The island is expected to erode back into the ocean in a matter of months.

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Pristine Seas -- National Geographic

Pristine Seas -- National Geographic | Communicating Science | Scoop.it

Learn about the Pristine Seas Expeditions from National Geographic.

Exploring and protecting some of the last truly wild places on the planet

National Geographic and Explorer-in-Residence Dr. Enric Sala launched the Pristine Seas project to find, survey, and help protect the last wild places in the ocean. It is essential that we let the world know that these places exist, that they are threatened, and that they deserve to be protected.

The Science & Education team's insight:

Again National Geographic has used a number modes of communication and brilliant graphic design. Look, learn and steal ideas.

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You probably haven't heard of these five amazing women scientists – so pay attention

You probably haven't heard of these five amazing women scientists – so pay attention | Communicating Science | Scoop.it

All week I’ve been intrigued and inspired by posters appearing in my department that depict truly great scientists, mathematicians and engineers. Few of them were known to me or my fellow students, yet their achievements include revolutionising algebra, developing the first treatment for leukaemia, and discovering fundamental processes in physics.

Their only common characteristic? They are women, and their appearance on the walls marks International Women’s Day. Try to recall a woman scientist and Marie Curie may be the first and perhaps only name that springs to mind. This is a shameful state of affairs, when for more than a century scientists who happen to be women have reached great scientific heights, despite the many barriers they faced on account of their gender.

So here are five women whose amazing discoveries and contribution to science should be as well-known and respected as those of Marie Curie.

 

Rosalind Franklin – crystallographyRosalind Franklin. Jewish Chronicle Archive/Heritage-Images

Only now is Rosalind Franklin’s (1920-1958) reputation recognised: a chemist, she was responsible for much of the X-ray crystallography research that was critical to the discovery of the famous double helical DNA structure.

She worked in a climate that was far from inclusive to women; her fellow scientists' attitude towards her are typified by James Watson’s book The Double Helix in which he is condescending throughout and refers to her as “Rosy”, a nickname she was known to dislike. Tragically, Franklin died from ovarian cancer in 1958, aged just 37. Four years later Francis Crick, James Watson and Maurice Wilkins, were awarded the Nobel Prize in Physiology or Medicine and famously omitted Franklin from their acceptance speech.

 

Lise Meitner – nuclear physicsLise Meitner in 1906. Churchill College Cambridge

Lise Meitner (1878-1968) was an Austrian physicist and the second woman to obtain a doctorate in physics at the University of Vienna in 1906, and the first woman in Germany to assume position of a full Professor of Physics in 1926. The annexation of Austria by Nazi Germany in 1938 forced Meitner to flee Germany due to her Jewish descent.

Meitner and Otto Hahn discovered nuclear fission in 1939, yet the 1944 Chemistry Nobel Prize was awarded only to Hahn who downplayed Meitner’s involvement. This was later described in Physics Today as “a rare instance in which personal negative opinions apparently led to the exclusion of a deserving scientist”.

 

Mary Anning – paleontologyMary Anning. Grey/Royal Geological Society

Mary Anning (1799-1847) was a self-educated palaeontologist from a poor background in Lyme Regis in the southwest of England. Her discoveries of the first complete Ichthyosaur in 1811 and a complete Plesiosaurus in 1823 established her as an expert in fossils and geology, which she played a key role in establishing as a new scientific discipline.

Her expertise was much sought-after by educated male contemporaries even though, as a woman, she was ineligible to join the Geological Society of London. However, by the time of her death from breast cancer aged 47, Anning had gained the respect of scientists and the general public for her work.

 

Gertrude Elion – pharmacologyGertrude Elion. Wellcome Foundation Archives, CC BY

Gertrude Elion (1918-1999) graduated from Hunter College in New York in 1937 with a degree in chemistry. Unable to complete a postgraduate degree due to the Great Depression, undeterred she spent time working as a lab assistant (for US$20 a week) and as a teacher until she obtained an assistant position at the Burroughs-Wellcome company.

Here she developed Purinethol, the first treatment for leukaemia, anti-malarial drug Pyrimethamine, and acyclovir, a treatment for viral herpes still sold today as Zovirax. Later Elion oversaw the adaptation of Azidothymidine, the first treatment for AIDS. In recognition of her achievements she was presented with the Nobel Prize in Physiology or Medicine in 1988, despite having never completed her PhD.

 

Jocelyn Bell Burnell – astrophysicsDame Jocelyn Bell Burnell. BBC

With a PhD in astrophysics from Cambridge University, Jocelyn Bell (1943-) built and worked on a radio telescope during her graduate studies. Here she discovered a repeating radio signal which, though it was initially dismissed by her colleagues, she traced to a rotating neutron star, later called a pulsar. For Jocelyn’s discovery of radio pulsars, described as “the greatest astronomical discovery of the 20th century”, her supervisor and his colleague were awarded the 1974 Nobel Prize in Physics.

Burnell was completely omitted as a co-recipient, to the outrage of many prominent astronomers at the time. However Burnell has gone on to receive many subsequent awards and honours, was President of the Royal Astronomical Society and the first women president of the Institute of Physics, and was appointed Dame Commander (DBE) of the Order of the British Empire in 2007.

 

Inspiration

My decision to study chemistry was inspired by my love for understanding the world around me and using science to help people. Learning about these incredibly tenacious women has kept me driven through tough weeks of thesis writing; the hardships they faced in their careers were immense in comparison to today.

Not only this, but it has reminded me of the amazing women colleagues around whom I am privileged to carry out my research. I spend time with scientists of many disciplines, all of whom inspire me daily. And while we women might happen to be fewer in number as scientists this has no bearing on our capacity to conduct intuitive, ground-breaking science now and for the future.

The Science & Education team's insight:

Gertrude Elion was the only one that I hadn't heard of and I talked about Rosalind Franklin in two tutorials this week

 

More from RIA http://riaus.org.au/articles/my-favourite-women-of-science

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Engaging the disengaged with science

Engaging the disengaged with science | Communicating Science | Scoop.it
Most science communication appeals to those who already love science. It's harder, but important, to reach out to the disengaged too.

Just as we don’t all have the same tastes or preferences for football codes or teams – or even genres of music or flavours of ice cream – so too we don’t all have the same tastes or preferences when it comes to science.

Last year the CSIRO released the results of a major survey into public attitudes towards science and technology, and found four key segments of the population that view science in very different ways:

A: Fan Boys and Fan Girls. This group is about 23% of the population and they are very enthusiastic about science and technology. Science is a big part of their lives and they think everyone should take an interest in it.

B: The Cautiously Keen make up about 28% of the public. They are interested in science and technology, but can be a little wary of it. They tend to believe that the benefits of science must be greater than any harmful effects.

C: The Risk Averse represent about 23% of the population. They are much more concerned about the risks of science and technology, including issues such as equality of access. Most of their values about science are framed in terms of risk.

D: The Concerned and Disengaged make up 20% of the population. They are the least enthusiastic and least interested in science and technology. Many of them don’t much trust it. They believe the pace of science and technology is too fast to keep up with and that science and technology create more problems than they solve.

Segment A are further away from the community average than any other segment CSIRO

Click to enlarge

If you are reading this article you are probably an A – and have self-selected to read the article as something you are interested in. But that is one of the problems: most audiences of science communications activities self-select from the As.

Interesting the disinterested

The research builds upon several other earlier surveys and its findings complement a 2014 survey designed by the Australian National University and conducted by Ipsos Public Affairs for the Inspiring Australia program.

This survey segmented Australians on the basis of how frequently they interacted with information about science and technology. It found that only half of the population could recall listening to, watching or reading something to do with science and technology, or even searching for science and technology information, at least once a fortnight. Also, 14% had much less frequent interactions with science and technology information.

So, while Merlin Crossley is quite right that we are increasingly well served by high-quality science communication activities, rather than simply needing even more, we believe we need a broader spread of activities, designed for different audiences who have different attitudes to science.

With science communication activities growing, the Fan Boys and Fan Girls have never had it so good. There are great science stories almost everywhere you turn, if you’re interested in those stories, of course.

But the CSIRO data showed that as many as 40% of the Australian public were unengaged, disinterested or wary of science – little changed since a similar Victorian government study in 2011.

So the growth in science communication is not necessarily growing its audience. To do that we need to align our science communication messages and channels with those that the disengaged and disinterested value.

Think of the football analogy mentioned above. A diehard AFL fan is not likely to seek out a rugby union match of their own volition. However, if you want to get them interested in rugby union, you might consider holding a demonstration match at an AFL game. Or even better, recruit AFL players to join one of the teams playing in the rugby union demo match.

More than blowing stuff up

There are many ways to get exciting science communication activities out of the existing channels and onto the Footy Shows and Today Shows of the world. Science communicators could show up at music and folk festivals and other community activities. They could get sports stars and TV personalities and musicians talking about science, much as the Inspiring Australia initiative has sought to do.

And they should think beyond BSU (blowing stuff up) approaches where the “wow” factor is high but longer term engagement is often quite low.

Bangs and stinks can be fun, but they don’t necessarily leave a lasting message. Sean Stayte/Flickr, CC BY-NC-SA

Click to enlarge

One of the other key findings of the CSIRO study was that the Fan Boys and Fan Girls are further away from the average point of community values than any other segment of the population. This means that Fan Boys or Girls probably have the least idea of what might appeal to the other segments. They know what turns them on, but they are probably only guessing what will work for the other segments.

So they need to recruit members of the other non-science fan segments to help devise science communication activities that appeal to them. For no one is going to understand the Bs, Cs and Ds like they understand themselves (even if they don’t much understand As!).

The Science & Education team's insight:

We are doing our bit.

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The Year of the Gibbon - RiAus

The Year of the Gibbon - RiAus | Communicating Science | Scoop.it

When we think of monkeys, we will generally picture a long armed primate, swinging through the trees. They’re gorgeous, and a little alien looking, but they’re monkeys. Actually, they’re gibbons. Gibbons are the group of primates that live in the tropical forests of Asia, and we often see them in zoos. But, why are they so important?

Well, not only is 2015 the Year of the Gibbon (according to International Union for Conservation of Nature), but Gibbons are the rarest primates on Earth, even though they are the largest group (when looking at number of species). Lots of species (both plant and animal) are on the brink of extinction, and the rate of extinction in animals today is higher than at any other known point in Earth’s history. So, what does this mean for the world’s Gibbons? Of the 16 known species, 1 is considered vulnerable, 11 as endangered and 4 as critically endangered on the IUCN RedList. In other words, the next species of primate to go extinct will probably be a Gibbon, most likely the Hainan Gibbon.

Gibbons are monogamous and live in family groups, they are also territorial. These areas, or home ranges can cover anywhere from 50 to 100 acres. Gibbons mark their territory using sound. It is a beautiful, and slightly eerie noise. They can also move incredibly fast through the treetops, sometimes travelling up to 56km/h (Usain Bolt can run at 45 km/h).

 

Gibbons are not only important figureheads of primates and creatures within their own right, they are also key parts of the ecosystems that they live in. Gibbons are frugivorous, meaning that they eat fruit, especially figs (a favourite delicacy). When Gibbons eat the fruit, they also eat the seed. This helps them to spread the plant’s seeds, and the next generation of trees to grow. So, the presence of Gibbons means that many different trees are able to spread their seeds and germinate, keeping the ecosystem of many tropical Asian forests thriving.

The competition between different species of Gibbons is also very important to the survival of these forests, not just the Gibbons. Different species occupy different areas of the forest and play different roles. But, they do overlap a little. This means that if one species goes extinct, another can move in to take its place. This can often lead to overgrazing and many other unforseen effects (known as indirect interactions).

So, Gibbons are incredibly important to the survival and maintenance of many forests throughout much of Asia. But, what is being done to save them from extinction? Well, announcing 2015 as the Year of the Gibbon was the first step. This has helped to pave the way for a number of initiatives across the globe. The IUCN / SSC Primate Specialist Group is one group that is spearheading this campaign. Other groups in Australia such as Perth Zoo are helping to promote awareness for the conservation of these amazing species. The International Primate Protection League is another great way to get involved in the conservation of this amazing and picturesque species, they also have a great Facebook page that lets you keep up-to-date with their work.

The Science & Education team's insight:

RIA puts out good, well digested, stories

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Newly discovered sea creature was once the largest animal on Earth

Newly discovered sea creature was once the largest animal on Earth | Communicating Science | Scoop.it
Fossil sheds light on the evolution of limbs in arthropods

 

Almost half a billion years ago, the largest animal on Earth was a 2-meter-long, helmet-headed sea creature that fed on some of the ocean’s tiniest prey. The newly described species is one of the largest arthropods yet discovered, a class of animals that includes spiders and crabs. The well-preserved remains of the multisegmented creature are providing clues about how subsequent arthropods’ legs may have evolved from the dozens of stubby flaps used to propel this beast through the water.

Fossils of the ancient leviathan were unearthed from 480-million-year-old rocks exposed on a hillside in southeastern Morocco. Besides a handful of relatively complete remains, researchers have recovered about 50 fragments that came from molted exoskeletons or decomposing carcasses before they were buried by sediment, says Peter Van Roy, a paleobiologist at Yale University. The largest nearly complete specimen measures about 1.3 meters long but likely would have stretched 1.6 meters if intact, he notes. Based on the sizes of isolated fragments, though, some of the creatures probably were about 2 meters long. It was likely the largest creature on Earth at the time, and only two other types of arthropods ever rivaled or exceeded it in size, the researchers report online today in Nature.

Van Roy and his colleagues dubbed the new species Aegirocassis benmoulae; Aegir is the god of the sea in Norse mythology, cassis is the Latin word for helmet, and benmoulae honors the Moroccan collector who first discovered fossils of the creature. Aegirocassis is a member of a group of creatures called anomalocaridids, a name derived from the Latin words for “strange shrimp.” Most known anomalocaridids were formidable predators, Van Roy says. But Aegirocassis, like a smaller and much older species of anomalocaridid, described last year, was a filter feeder that sifted millimeter-sized creatures—possibly including tiny crustaceans or the larvae of other marine organisms—from the water as it swam.

“Filter feeding and gigantism are associated, which is a pattern we see in different groups of animals across the tree of life,” says Gregory Edgecombe, a paleobiologist at the Natural History Museum in London, who wasn’t involved in the research. Just think of the filter-feeding leviathans swimming in today’s seas: The blue whale is the largest animal on Earth, tipping the scales at up to 190 metric tons despite feeding only on small free-swimming crustaceans, including the thumb-sized or smaller creatures called krill. Likewise, Van Roy and his colleagues note, in past eras several species of fish and sharks have evolved to huge proportions by directly exploiting the vast bounty at the base of the ocean’s food chain.

The new fossils also fill a critical gap in arthropod evolution, Van Roy says. In particular, they provide key insights into the evolution of arthropod limbs. Aquatic arthropods—today’s crustaceans such as shrimp, crabs, and lobsters as well as ancient creatures such as trilobites and sea scorpions—have limbs with two branches, one of which bears weight and another that is typically adorned with gills. Large gaps in the fossil record have previously obscured the origins of this configuration, but Aegirocassis provides the first look at how water-dwelling arthropods’ two-branched legs may have evolved. “This species is a very important intermediate, a transitional form,” says Javier Ortega-Hernández, a paleobiologist at the University of Cambridge in the United Kingdom, who wasn’t involved in the research. Although anomalocaridids died out (and thus aren’t the direct ancestors of any living arthropod lineage), they likely shared many anatomical features with close relatives living at the time that ended up on the surviving branches of life’s family tree, he explains.

Many Aegirocassis fossils that the team analyzed were preserved in three dimensions rather than being squished flat by accumulating sediments, as many previously described anomalocaridids had been. That enabled Van Roy and his team to see that each of the creature’s 11 segments had two flaps on each side—both of which helped propel the beast through the water, but the upper flap also seems to have been associated with the creature’s gills. Rather than undulating its entire body, Aegirocassis probably moved its lower flaps up and down in sequence, similar to the way a cuttlefish undulates its fleshy mantle (or sports fans repeatedly stand and sit as they “do the wave” in a stadium).

Through time and over generations, Van Roy and his colleagues suggest, arthropod species evolved such that the upper and lower flaps fused into one structure, with a stubby base and two branches growing from it. One branch came to bear the weight of walking whereas the other retained the gills. Many of today’s land-dwelling arthropods have legs with only one branch, having lost the need for gills as they developed other methods of breathing, he notes.

The 3D nature of the Aegirocassis fossils “made it easier to visualize what structures are on the upper surface versus the lower surface” of the creature, Edgecombe says. With previous teams having only strongly flattened fossils to analyze, he notes, “some really basic questions about how the body of anomalocaridids is arranged have had us chasing our tails for years.”

The Science & Education team's insight:

Another example of the Cambrian explosion.

 

See Gould, S. J. (1991). Wonderful life: The Burgess Shale and the nature of history. London: Penguin. it is old but a great story and in the Library

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Colima Volcano - 21st Jan 15

The Science & Education team's insight:

Colima is one of the more active volcanoes in Mexico http://en.wikipedia.org/wiki/Volc%C3%A1n_de_Colima

There is also a smaller eruption on 11th Jan. You can watch it on a webcam on Webcams of Mexic http://www.webcamsdemexico.com/webcam-volcan-de-colima.html

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Science Gossip: A new citizen science project

Science Gossip: A new citizen science project | Communicating Science | Scoop.it

Click here to edit the title

About ‘Science Gossip’

The publication of books and periodicals are key locations for visualizing knowledge about the natural world. The Biodiversity Heritage Library has digitized and catalogued millions of pages of printed text between the 1400's and today related to the investigation of the natural world. Illustrations are a large part of these printed pages, and we need your to help identify, classify and correlate them. The data you create by tagging illustrations and adding artist and engraver information will have a direct impact on the research of historians who are trying to figure out why, how often, and who made images depicting a whole range of natural sciences in the Victorian period.

BHL and Constructing Scientific Communities

‘Science Gossip’ is born from a collaboration between an Arts and Humanities Research Council project in the UK, called ‘Constructing Scientific Communities: Citizen Science in the 19th and 21st Centuries’ (ConSciCom) and the Missouri Botanical Garden who are providing content from the Biodiversity Heritage Library (BHL).

BHL is currently engaged in several citizen science initiatives that help leverage the crowd in improving access to its content. Projects include: Art of Life, where the public helps in describing natural history images; Purposeful Gaming and BHL where players engage in online games to help with text correction; Mining Biodiversity where annotators help train mining algorithms for named entities, such as taxa, places, habitats and traits; and the Field Book Project where “volunpeers” transcribe hand-written field book content. More information about these projects can be found in the BHL blog post on Crowdsourcing and BHL

The ConSciCom project is investigating the role of naturalists and ‘amature’ science enthusiasts in the making and communication of science in both the Victorian period and today. Historians at the Universities of Leicester and Oxford are investigating the particular roles of the periodical press in the nineteenth century as an arena in which citizen scientists of the past participated in scientific research. Periodicals and books of the Victorian era were heavily illustrated, but little is know about who made the illustrations and how they ended up in print. The data you create by tagging illustrations and adding artist and engraver information will have a direct impact on the research of historians who are trying to figure out why, how often, and who made images depicting a whole range of natural sciences in the Victorian period.

Better understanding the range of individuals who made science through their images will help us ascertain what constituted a nineteenth century scientist and citizen scientist. This is the first Zooniverse project where citizen scientists are both the researchers and the subject of the research. Citizen scientists of today can have a direct impact on how we understand historical and modern notions of what it means to do science.

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Scientific posters: Why?

Scientific posters: Why? | Communicating Science | Scoop.it

Scientists frequently lament the scarcity of effective scientific communicators—those who can explain complex concepts to the public, present scientifically sound alternatives to policy-makers, and make cogent arguments for the value of science to society. A few stellar programs are designed to select and train elite articulators, but some simple steps can improve the communication skills of all scientists. Most researchers learn how to talk about science at meetings. If scientists cannot explain their work clearly and succinctly to their peers, it is highly unlikely that they can explain it effectively to nonspecialists. I recently helped to judge student papers at a large scientific meeting, an experience that brought to my attention the importance of such communication early in one's career. I offer a few tips on how to make the most of this invaluable training.

“Training the next generation of scientists to communicate well should be a priority.”

PHOTO: PAUL SMITS/FLICKR

I encourage students to request a poster presentation at a large meeting. This format can be less stressful than speaking in front of a large audience. Furthermore, the student personally converses with members of the scientific community who share an interest in his or her research. The back-and-forth is good training and a reminder to students that discussing their research with experts or nonexperts should be a two-way conversation. Another advantage of presenting a poster is that the student can tailor the narrative to the interests of whoever stops by, in a Q&A exchange. I recall years ago when a graduate student was disappointed that her research would be described “only” in this format, until one of the giants in her field spent considerable time at her poster to discuss the work. As he left, he said, “I wish I had thought of that.” She was later hired into his department.

To be effective, posters need to be eye-catching as well as informative. In a convention hall lined with poster boards, scientists will bypass those with large blocks of texts and tables of impenetrable numbers. A cartoon that summarizes the model or findings, attractive displays of data, and photos that illustrate the experiment are good ways to grab attention. Creative ways to display pertinent information are a definite plus. I personally like posters that begin with the motivation for the work and end with the findings, areas for follow up, and broader implications of the results.

A 10-minute talk at a major conference is more difficult to organize and effectively deliver than an hour-long seminar. Mistakes that students often commit in preparing slides for a brief presentation are to show the same intricate multipart figures that they used in a research paper, have too much text (and in a font size too small), choose colors with insufficient contrast against the background, and use blurry images copied from the Internet. The delivery is also critical. Enthusiasm is one of the very best elements of any talk. Students should never merely recite from their slides and should never ever go over time. Recognizing who the audience is and pitching the talk appropriately are essential. Many years ago, if a scientist used unfamiliar jargon and aimed the presentation over the heads of the audience, the speaker might just have been considered smart. No longer. Today, such a speaker is viewed as a poor communicator.

Training the next generation of scientists to communicate well should be a priority. Departments could arrange for students to hold mock presentations for other faculty, researchers, and students in advance of their presentations at conferences—a dress rehearsal before the main event. And researchers attending meetings should take some time to judge a few student papers, visit student posters, or attend student talks. This feedback to young scientists is invaluable, and the great communicators that will emerge may well trace their sharpened skills back to a moment at their poster or at the podium.

The Science & Education team's insight:

Another reason to practice producing posters

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Brian Schmidt: why funding science infrastructure is essential

Brian Schmidt: why funding science infrastructure is essential | Communicating Science | Scoop.it
The government is holding crucial science infrastructure funding hostage until its higher education reforms are passed by the senate.

 

When you see the word “infrastructure”, the first thing conjured in most people’s minds is roads, bridges and rail. These are, after all, the most visible portion of the A$100 billion of infrastructure that the nation is currently investing in.

But there is another kind of infrastructure that is just as critical to Australia’s economy and future which you probably haven’t heard of. That is the national infrastructure that underpins our scientific research and development.

Over the past decade the nation has invested A$2.5 billion in national research infrastructure investment across a diverse range of 27 facilities.

These include telescopes that allow astronomers like myself to undertake internationally significant scientific research. As well as leading edge imaging devices that enable companies like Cochlear to remain at the forefront of their industry.

Another example is the Integrated Marine Observing System. This provides valuable observations used for predicting everything from where the wreckage of missing Malaysia Airlines flight MH370 may have drifted, to information used to predict the seasonal forecasts so valuable for Australia’s farmers.

Much of this infrastructure was provided through the National Collaborative Research Infrastructure Strategy (NCRIS) announced in 2004 by the then Minister for Education, Science and Training, Julie Bishop. It was an innovative five year program that strategically invested in research infrastructure in a coordinated way across the nation.

Widely applauded across the sector, the initiative lost momentum under Labor starting in 2011, when it was not funded.

Instead, a band-aid solution was applied in 2012, funded by money destined for universities, to keep facilities from shutting down. This piece-meal approach was extended through a short-term program to fund operations available for the 2013-14 financial years.

Framework for science

Many scientists have commented on the loss of the strategic value embedded in the original NCRIS program, including myself and Peter Doherty in 2013.

However, the community was positively reassured when in 2014, as part of its first budget, Minister Christopher Pyne announced A$150 million for NCRIS for 2015-16 to allow the research infrastructure of the nation to continue to operate. And, very importantly, this created a path to the future by initiating Review of Research Infrastructure chaired by Philip Clark AM. This panel is expected to provide an interim report in a few weeks and deliver its final report in May.

The Integrated Marine Observing System deploys floats like these to monitor global ocean temperatures. Some of its funding comes from NCRIS. Alicia Navidad/CSIRO

Click to enlarge

It is the supreme hope of the research community that this report will once again provide the framework for a long-term strategic investment strategy for the nation that the government can invest in.

It is therefore almost unthinkable that the community now finds itself on the verge of calamity. The A$150 million of funds, promised in the 2014 Budget, have not been released by the Government due to the release being linked to the passage of the Higher Education Bill.

There is less than five months until insolvency for some facilities, and no sign that the higher education reforms will pass, despite their support from the higher education sector. Thus panic is beginning to creep into many of 27 research facilities, with key members of staff becoming increasing unsure of their future.

As they should be. Some facilities will need to start terminating their employees at the end of the month to ensure their balance sheets add up in June. These are highly skilled workers whom you cannot just recruit with an advert on Seek, so we are already losing significant capacity.

Funding science into the future

Catastrophe is if we still do not have a resolution before the 2015 budget in May. At this point it will be necessary for a wholesale winding down of the nation’s scientific infrastructure capability.

And just like if a key infrastructure provider, such as Telstra, needed to shut down and quit providing services, the damage will be immense. This will not just be to the facilities themselves, but to the nation as a whole, through the effects on the A$30 billion of R&D spent each year and the 35,000 people which depend on the infrastructure provided.

Higher education needs to be reformed, although I am concerned by the current proposal. However, my discussions with cross bench senators suggest that the prospects of any higher education reform package passing the Senate before May are low.

This is why the Research Alliance, a group of scientific, research and university bodies, today have written an open letter calling on the prime minister Tony Abbott to honour the government’s commitment to this infrastructure program.

Our national research infrastructure needs an urgent solution independent of the higher education reform package, and I beg the Senate and the government to find a solution.

The cost of not doing so will dwarf the A$150 million one-off payment this year.

The Science & Education team's insight:

Another plea from the great and good in science which also cogently interrogates the nature of science

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We must defend science if we want a prosperous future

We must defend science if we want a prosperous future | Communicating Science | Scoop.it
Our nation’s future depends on the quality of its thinking and its leaders. As such, science must be at the core of our national discourse.
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Another old man saying what we know is true

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Feature: Physicists gear up to catch a gravitational wave

Feature: Physicists gear up to catch a gravitational wave | Communicating Science | Scoop.it
After decades of work, physicists say they are a year or two away from detecting ripples in spacetime

 

This patch of woodland just north of Livingston, Louisiana, population 1893, isn’t the first place you’d go looking for a breakthrough in physics. Standing on a small overpass that crosses an odd arching tunnel, Joseph Giaime, a physicist at Louisiana State University (LSU), 55 kilometers west in Baton Rouge, gestures toward an expanse of spindly loblolly pine, parts of it freshly reduced to stumps and mud. “It’s a working forest,” he says, “so they come in here to harvest the logs.” On a quiet late fall morning, it seems like only a logger or perhaps a hunter would ever come here.

Yet it is here that physicists may fulfill perhaps the most spectacular prediction of Albert Einstein’s theory of gravity, or general relativity. The tunnel runs east to west for 4 kilometers and meets a similar one running north to south in a nearby warehouselike building. The structures house the Laser Interferometer Gravitational-Wave Observatory (LIGO), an ultrasensitive instrument that may soon detect ripples in space and time set off when neutron stars or black holes merge.

Einstein himself predicted the existence of such gravitational waves nearly a century ago. But only now is the quest to detect them coming to a culmination. The device in Livingston and its twin in Hanford, Washington, ran from 2002 to 2010 and saw nothing. But those Initial LIGO instruments aimed only to prove that the experiment was technologically feasible, physicists say. Now, they’re finishing a $205 million rebuild of the detectors, known as Advanced LIGO, which should make them 10 times more sensitive and, they say, virtually ensure a detection. “It’s as close to a guarantee as one gets in life,” says Peter Saulson, a physicist at Syracuse University in New York, who works on LIGO.

Detecting those ripples would open a new window on the cosmos. But it won’t come easy. Each tunnel contains a pair of mirrors that form an “optical cavity,” within which infrared light bounces back and forth. To look for the stretching of space, physicists will compare the cavities’ lengths. But they’ll have to sense that motion through the din of other vibrations. Glancing at the pavement on the overpass, Giaime says that the ground constantly jiggles by about a millionth of a meter, shaken by seismic waves, the rumble of nearby trains, and other things. LIGO physicists have to shield the mirrors from such vibrations so that they can see the cavities stretch or shorten by distances 10 trillion times smaller—just a billionth the width of an atom.

IN 1915, Einstein explained that gravity arises when mass and energy warp space and time, or spacetime. A year later, he predicted that massive objects undergoing the right kind of oscillating motion should emit ripples in spacetime—gravitational waves that zip along at light speed.

For decades that prediction remained controversial, in part because the mathematics of general relativity is so complicated. Einstein himself at first made a technical error, says Rainer Weiss, a physicist at the Massachusetts Institute of Technology (MIT) in Cambridge. “Einstein had it right,” he says, “but then he [messed] up.” Some theorists argued that the waves were a mathematical artifact and shouldn’t actually exist. In 1936, Einstein himself briefly took that mistaken position.

© MATT WEBER

 

Rainer Weiss of the Massachusetts Institute of Technology laid out the basic plan for LIGO 43 years ago.

 

Even if the waves were real, detecting them seemed impossible, Weiss says. At a time when scientists knew nothing of the cosmos’s gravitational powerhouses—neutron stars and black holes—the only obvious source of waves was a pair of stars orbiting each other. Calculations showed that they would produce a signal too faint to be detected.

By the 1950s, theorists were speculating about neutron stars and black holes, and they finally agreed that the waves should exist. In 1969, Joseph Weber, a physicist at the University of Maryland, College Park, even claimed to have discovered them. His setup included two massive aluminum cylinders 1.5 meters long and 0.6 meters wide, one of them in Illinois. A gravitational wave would stretch a bar and cause it to vibrate like a tuning fork, and electrical sensors would then detect the stretching. Weber saw signs of waves pinging the bars together. But other experimenters couldn’t reproduce Weber’s published results, and theorists argued that his claimed signals were implausibly strong.

Still, Weber’s efforts triggered the development of LIGO. In 1969, Weiss, a laser expert, had been assigned to teach general relativity. “I knew bugger all about it,” he says. In particular, he couldn’t understand Weber’s method. So he devised his own optical method, identifying the relevant sources of noise. “I worked it out for myself, and I gave it to the students as a homework problem,” he says.

Weiss’s idea, which he published in 1972 in an internal MIT publication, was slow to catch on. “It was obvious to me that this was pie in the sky and it would never work,” recalls Kip Thorne, a theorist at the California Institute of Technology (Caltech) in Pasadena, California. Thorne recorded his skepticism in Gravitation, the massive textbook that he co-wrote and published in 1973. “I had an exercise that said ‘Show that this technology will never work to detect gravitational waves,’ ” Thorne says.

But by 1978 Thorne had warmed to the idea, and he persuaded Caltech to put up $2 million to build a 40-meter prototype interferometer. “It wasn’t a hard sell at all,” Thorne says, “which was a contrast to the situation at MIT.” Weiss says that Thorne played a vital role in winning support for a full-scale detector from the National Science Foundation in 1990. Construction in Livingston and Hanford finally began in 1994.

Now, many physicists say Advanced LIGO is all but a sure winner. On a bright Monday morning in December, researchers at Livingston are embarking on a 10-day stint that will mark their first attempt to run as if making observations. LIGO Livingston has the feel of an outpost. Roughly 30 physicists, engineers, technicians, and operators gather in the large room that serves as the facility’s foyer, auditorium, and—with a table-tennis table in one corner—rec room. “Engineering run 6 began 8 minutes ago,” announces Janeen Romie, an engineer from Caltech. It seems odd that so few people can run such a big rig.

But in principle, LIGO is simple. Within the interferometer’s sewer pipe–like vacuum chamber, at the elbow of the device, a laser beam shines on a beam splitter, which sends half the light down each of the interferometer’s arms. Within each arm, the light builds up as it bounces between the mirrors at either end. Some of the light leaks through the mirrors at the near ends of the arms and shines back on the beam splitter. If the two arms are exactly the same length, the merging waves will overlap and interfere with each other in a way that directs the light back toward the laser.

The ultimate motion sensor

In a LIGO interferometer, light waves leaking out of the two storage arms ordinarily interfere to send light back to the laser. By stretching the two arms by different amounts, a gravitational wave would alter the interference and send light toward a photodetector.

G. GRULLÓN/SCIENCE

But if the lengths are slightly different, then the recombining waves will be out of sync and light will emerge from the beam splitter perpendicular to the original beam. From that “dark port” output, physicists can measure any difference in the arms’ lengths to an iota of the light’s wavelength. Because a gravitational wave sweeping across the apparatus would generally stretch one arm more than the other, it would cause light to warble out of the dark port at the frequency at which the wave ripples. That light would be the signal of the gravitational wave.

In practice, LIGO is a monumental challenge in sifting an infinitesimal signal from a mountain of vibrational noise. Sources of gravitational waves should “sing” at frequencies ranging from 10 to 1000 cycles per second, or hertz. But at frequencies of hundreds or thousands of hertz the individual photons in the laser beam produce noise as they jostle the mirrors. To smooth out such noise, researchers crank up the amount of light and deploy massive mirrors. At frequencies of tens of hertz and lower, seismic vibrations dominate, so researchers dangle the mirrors from elaborate suspension systems and actively counteract that motion. Still, a large earthquake anywhere in the world or even the surf pounding the distant coast can knock the interferometer off line.

To boost the Hanford and Livingston detectors’ sensitivity 10-fold, to a ten-billionth of a nanometer, physicists have completely rebuilt the devices. Each of the original 22-kilogram mirrors hung like a pendulum from a single steel fiber; the new 40-kilogram mirrors hang on silica fibers at the end of a four-pendulum chain. Instead of LIGO’s original 10 kilowatts of light power, researchers aim to circulate 750 kilowatts. They will collect 100,000 channels of data to monitor the interferometer. Comparing the new and old LIGO is “like comparing a car to a wheel,” says Frederick Raab, a Caltech physicist who leads the Hanford site.

The new Livingston machine has already doubled Initial LIGO’s sensitivity. “In 6 months they’ve made equivalent progress to what Initial LIGO made in 3 or 4 years,” says Raab, who adds that the Hanford site is about 6 months behind. But Valery Frolov, a Caltech physicist in charge of commissioning the Livingston detector, cautions that machine isn’t running anywhere close to specs. The seismic isolation was supposed to be better, he says, and researchers haven’t been able to keep the interferometer “locked” and running for long periods. As for reaching design sensitivity, “I don’t know whether it will take 1 year or whether it will take 5 years like Initial LIGO did,” he warns.

Still, LIGO researchers plan to make a first observing run this year and hope to reach design sensitivity next year. “We will have detections that we will be able to stand up and defend, if not in 2016, then in 2017 or 2018,” says Gabriela González, a physicist at LSU and spokesperson for the more than 900-member LIGO Science Collaboration.

That forecast is based on the statistics of the stars. LIGO’s prime target is the waves generated by a pair of neutron stars—the cores of exploded stars that weigh more than the sun but measure tens of kilometers across—whirling into each other in a death spiral lasting several minutes. Initial LIGO could sense such a pair up to 50 million light-years way. Given the rarity of neutron-star pairs, that search volume was too small to guarantee seeing one. Advanced LIGO should see 10 times as far and probe 1000 times as much space, enough to contain about 10 sources per year, González says. However, Clifford Will, a theorist at the University of Florida in Gainesville, notes that the number of sources is the most uncertain part of the experiment. “If it’s less than one per year, that’s not going to be too good,” he says.

Enlarging the search

Compared with Initial LIGO, Advanced LIGO will be able to detect gravitational wave sources up to 10 times as far away, probing 1000 times as much space. Such a volume will likely yield multiple sources.

ADAPTED FROM NSF BY G. GRULLÓN/SCIENCE

The hunt will be global. As well as combining data from the two LIGO detectors, researchers will share data with their peers working on the VIRGO detector, an interferometer with 3-kilometer arms near Pisa, Italy, that is undergoing upgrades, and on GEO600, one with 600-meter arms near Hannover, Germany. By comparing data, collaborators can better sift signals from noise and can pinpoint sources on the sky. Japanese researchers are also building a detector, and LIGO leaders hope to add a third detector, in India.

FOR THEORISTS—if not for the rest of the world—seeing gravitational waves for the first time will be something of an anti-climax. “We are so confident that gravitational waves exist that we don’t actually need to see one,” says Marc Kamionkowski, a theorist at Johns Hopkins University in Baltimore, Maryland. That’s because in 1974 American astrophysicists Russell Hulse and Joseph Taylor Jr. found indirect but convincing evidence of the waves. They spotted two pulsars—neutron stars that emit radio signals with clockwork regularity—orbiting each other. From the timing of the radio pulses, Hulse and Taylor could monitor the pulsars’ orbit. They found it is decaying at exactly the rate expected if the pulsars were radiating energy in the form of gravitational waves.

LIGO’s real payoff will come in opening a new frontier in astronomy, says Robert Wald, a gravitational theorist at the University of Chicago in Illinois. “It’s kind of like after being able to see for a while, being able to hear, too,” Wald says. For example, if a black hole tears apart a neutron star, then details of the gravitational waves may reveal the properties of matter in neutron stars.

All told, detecting gravitational waves would merit science’s highest accolade, physicists say. “As soon as they detect a gravitational wave, it’s a Nobel Prize,” Kamionkowski predicts. “It’s such an extraordinary experimental accomplishment.” But the prize can be shared by at most three people, so the question is who should get it.

Weiss is a shoo-in, many say, but he demurs. “I don’t want to deny that there was some innovation [in my work], but it didn’t come out of the blue,” he says. “The lone crazy man working in a box, that just doesn’t hold true.” In 1962 two Russian physicists published a paper on detecting gravitational waves with an interferometer, as Weiss says he learned long after his 1972 work. In the 1970s, Robert Forward of the Hughes Aircraft Company in Malibu, California, ran a small interferometer. Key design elements of LIGO came from Ronald Drever, project director at Caltech from 1979 to 1987, who, Thorne says, “has to be recognized as one of the fathers of the LIGO idea.”

But to make that prize-winning discovery, physicists must get Advanced LIGO up and running. At 8 a.m. on Tuesday morning, LIGO operator Gary Traylor comes off the night shift. “Last night was a total washout,” he says in his soft Southern accent, swiveling in a chair in the brightly lit control room. “There’s a low pressure area moving over the Atlantic that’s causing 20-foot waves to crash into the coast,” Traylor says, and that distant drumming overwhelmed the detector. So in the small hours, LIGO did sense waves. But not the ones everybody is hoping to see.

The Science & Education team's insight:

a good intro to an interesting corner of physics research

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