Category Archives: science

Frogs: monitoring them, finding new species, and research about the golden ones in Panama

I have three frog-oriented items and while they’re not strictly speaking in my usual range of topics, given this blog’s name and the fact I haven’t posted a frog piece in quite a while, it seems this is a good moment to address that lack.

Monitoring frogs and amphibians at Trent University (Ontario, Canada)

From a March 23, 2015 Trent University news release,

With the decline of amphibian populations around the world, a team of researchers led by Trent University’s Dr. Dennis Murray will seek to establish environmental DNA (eDNA) monitoring of amphibian occupancy and aquatic ecosystem risk assessment with the help of a significant grant of over $596,000 from the Natural Sciences and Engineering Research Council of Canada (NSERC).

Awarded to Professor Murray, a Canada research chair in integrative wildlife conservation, bioinformatics, and ecological modelling and professor at Trent University along with colleagues Dr. Craig Brunetti of the Biology department, and Dr. Chris Kyle of the Forensic Science program, and partners at Laurentian University, University of Toronto, McGill University, Ontario Ministry of Natural Resources and Forestry and Environment Canada, the grant will support the development of tools that will promote a cleaner aquatic environment.

The project will use amphibian DNA found in natural breeding habitats to determine the presence and abundance of amphibians as well as their pathogens. This new technology capitalizes on Trent University’s expertise and infrastructure in the areas of wildlife DNA and water quality.

“We’re honoured to have received the grant to help us drive the project forward,” said Prof. Murray. “Our plan is to place Canada, and Trent, in a leadership position with respect to aquatic wildlife monitoring and amphibian conservation.”

Amphibian populations are declining worldwide, yet in Canada, amphibian numbers are not monitored closely, meaning changes in their distribution or abundance may be unnoticeable. Amphibian monitoring in Canada is conducted by citizen scientists who record frog breeding calls when visiting bodies of water during the spring. However, the lack of formalized amphibian surveys leaves Canada in a vulnerable position regarding the status of its diverse amphibian community.

Prof. Murray believes that the protocols developed from this project could revolutionize how amphibian populations are monitored in Canada and in turn lead to new insights regarding the population trends for several amphibian species across the country.

Here’s more about NSERC and Trent University from the news release,

About NSERC

NSERC is a federal agency that helps make Canada a country of discoverers and innovators. The agency supports almost 30,000 post-secondary students and postdoctoral fellows in their advanced studies. NSERC promotes discovery by funding approximately 12,000 professors every year and fosters innovation by encouraging over 2,400 Canadian companies to participate and invest in post-secondary research projects.

The NSERC Strategic Project Grants aim to increase research and training in areas that could strongly influence Canada’s economy, society or environment in the next 10 years in four target areas: environmental science and technologies; information and communications technologies; manufacturing; and natural resources and energy.

About Trent University

One of Canada’s top universities, Trent University was founded on the ideal of interactive learning that’s personal, purposeful and transformative. Consistently recognized nationally for leadership in teaching, research and student satisfaction, Trent attracts excellent students from across the country and around the world. Here, undergraduate and graduate students connect and collaborate with faculty, staff and their peers through diverse communities that span residential colleges, classrooms, disciplines, hands-on research, co-curricular and community-based activities. Across all disciplines, Trent brings critical, integrative thinking to life every day. As the University celebrates its 50th anniversary in 2014/15, Trent’s unique approach to personal development through supportive, collaborative community engagement is in more demand than ever. Students lead the way by co-creating experiences rooted in dialogue, diverse perspectives and collaboration. In a learning environment that builds life-long passion for inclusion, leadership and social change, Trent’s students, alumni, faculty and staff are engaged global citizens who are catalysts in developing sustainable solutions to complex issues. Trent’s Peterborough campus boasts award-winning architecture in a breathtaking natural setting on the banks of the Otonabee River, just 90 minutes from downtown Toronto, while Trent University Durham delivers a distinct mix of programming in the GTA.

Trent University’s expertise in water quality could be traced to its proximity to Canada’s Experimental Lakes Area (ELA), a much beleaguered research environment due to federal political imperatives. You can read more about the area and the politics in this Wikipedia entry. BTW, I am delighted to learn that it still exists under the auspices of the International Institute for Sustainable Development (IISD),

Taking this post into nanotechnology territory while mentioning the ELA, Trent University published a Dec. 8, 2014 news release about research into silver nanoparticles,

For several years, Trent University’s Dr. Chris Metcalfe and Dr. Maggie Xenopoulos have dedicated countless hours to the study of aquatic contaminants and the threat they pose to our environment.

Now, through the efforts of the International Institute for Sustainable Development (IISD), their research is reaching a wider audience thanks to a new video (Note: A link has been removed).

The video is one of a five-part series being released by the IISD that looks into environmental issues in Canada. The video entitled “Distilling Science at the Experimental Lakes Area: Nanosilver” and featuring Professors Metcalfe and Xenopoulos profiles their research around nanomaterials at the Experimental Lakes Area.

Prof. Xenopolous’ involvement in the project falls in line with other environmental issues she has tackled. In the past, her research has examined how human activities – including climate change, eutrophication and land use – affect ecosystem structure and function in lakes and rivers. She has also taken an interest in how land use affects the material exported and processed in aquatic ecosystems.

Prof. Metcalfe’s ongoing research on the fate and distribution of pharmaceutical and personal care products in the environment has generated considerable attention both nationally and internationally.

Together, their research into nanomaterials is getting some attention. Nanomaterials are submicroscopic particles whose physical and chemical properties make them useful for a variety of everyday applications. They can be found in certain pieces of clothing, home appliances, paint, and kitchenware. Initial laboratory research conducted at Trent University showed that nanosilver could strongly affect aquatic organisms at the bottom of the food chain, such as bacteria, algae and zooplankton.

To further examine these effects in a real ecosystem, a team of researchers from Trent University, Fisheries and Oceans Canada and Environment Canada has been conducting studies at undisclosed lakes in northwestern Ontario. The Lake Ecosystem Nanosilver (LENS) project has been monitoring changes in the lakes’ ecosystem that occur after the addition of nanosilver.

“In our particular case, we will be able to study and understand the effects of only nanosilver because that is the only variable that is going to change,” says Prof. Xenopoulos. “It’s really the only place in the world where we can do that.”

The knowledge gained from the study will help policy-makers make decisions about whether nanomaterials can be a threat to aquatic ecosystems and whether regulatory action is required to control their release into the environment.

You can find the 13 mins. video here: https://www.youtube.com/watch?v=_nJai_B4YH0#action=share

Shapeshifting frogs, a new species in Ecuador

Caption: This image shows skin texture variation in one individual frog (Pristimantis mutabilis) from Reserva Las Gralarias. Note how skin texture shifts from highly tubercular to almost smooth; also note the relative size of the tubercles on the eyelid, lower lip, dorsum and limbs. Credit: Zoological Journal of the Linnean Society

Caption: This image shows skin texture variation in one individual frog (Pristimantis mutabilis) from Reserva Las Gralarias. Note how skin texture shifts from highly tubercular to almost smooth; also note the relative size of the tubercles on the eyelid, lower lip, dorsum and limbs.
Credit: Zoological Journal of the Linnean Society

Here’s more about the shapeshifting and how the scientists figured out what the frogs were doing (from a March 23, 2015 Case Western Research University news release on EurekAlert; Note: A link has been removed),

A frog in Ecuador’s western Andean cloud forest changes skin texture in minutes, appearing to mimic the texture it sits on.

Originally discovered by a Case Western Reserve University PhD student and her husband, a projects manager at Cleveland Metroparks’ Natural Resources Division, the amphibian is believed to be the first known to have this shape-shifting capability.

But the new species, called Pristimantis mutabilis, or mutable rainfrog, has company. Colleagues working with the couple recently found that a known relative of the frog shares the same texture-changing quality–but it was never reported before.

The frogs are found at Reserva Las Gralarias, a nature reserve originally created to protect endangered birds in the Parish of Mindo, in north-central Ecuador.

The researchers, Katherine and Tim Krynak, and colleagues from Universidad Indoamérica and Tropical Herping (Ecuador) co-authored a manuscript describing the new animal and skin texture plasticity in the Zoological Journal of the Linnean Society this week. They believe their findings have broad implications for how species are and have been identified. The process may now require photographs and longer observations in the field to ensure the one species is not mistakenly perceived as two because at least two species of rain frogs can change their appearance.

Katherine Krynak believes the ability to change skin texture to reflect its surroundings may enable P. mutabilis to help camouflage itself from birds and other predators.

The Krynaks originally spotted the small, spiny frog, nearly the width of a marble, sitting on a moss-covered leaf about a yard off the ground on a misty July night in 2009. The Krynaks had never seen this animal before, though Tim had surveyed animals on annual trips to Las Gralarias since 2001, and Katherine since 2005.

They captured the little frog and tucked it into a cup with a lid before resuming their nightly search for wildlife. They nicknamed it “punk rocker” because of the thorn-like spines covering its body.

The next day, Katherine Krynak pulled the frog from the cup and set it on a smooth white sheet of plastic for Tim to photograph. It wasn’t “punk “–it was smooth-skinned. They assumed that, much to her dismay, she must have picked up the wrong frog.

“I then put the frog back in the cup and added some moss,” she said. “The spines came back… we simply couldn’t believe our eyes, our frog changed skin texture!

“I put the frog back on the smooth white background. Its skin became smooth.”

“The spines and coloration help them blend into mossy habitats, making it hard for us to see them,” she said. “But whether the texture really helps them elude predators still needs to be tested.”

During the next three years, a team of fellow biologists studied the frogs. They found the animals shift skin texture in a little more than three minutes.

Juan M. Guayasamin, from Universidad Tecnológica Indoamérica, Ecuador, the manuscript’s first author, performed morphological and genetic analyses showing that P. mutabilis was a unique and undescribed species. Carl R. Hutter, from the University of Kansas, studied the frog’s calls, finding three songs the species uses, which differentiate them from relatives. The fifth author of the paper, Jamie Culebras, assisted with fieldwork and was able to locate a second population of the species. Culebras is a member of Tropical Herping, an organization committed to discovering, and studying reptiles and amphibians.

Guayasamin and Hutter discovered that Prismantis sobetes, a relative with similar markings but about twice the size of P. mutabilis, has the same trait when they placed a spiny specimen on a sheet and watched its skin turn smooth. P. sobetes is the only relative that has been tested so far.

Because the appearance of animals has long been one of the keys to identifying them as a certain species, the researchers believe their find challenges the system, particularly for species identified by one or just a few preserved specimens. With those, there was and is no way to know if the appearance is changeable.

The Krynaks, who helped form Las Gralarias Foundation to support the conservation efforts of the reserve, plan to return to continue surveying for mutable rain frogs and to work with fellow researchers to further document their behaviors, lifecycle and texture shifting, and estimate their population, all in effort to improve our knowledge and subsequent ability to conserve this paradigm shifting species.

Further, they hope to discern whether more relatives have the ability to shift skin texture and if that trait comes from a common ancestor. If P. mutabilis and P. sobetes are the only species within this branch of Pristimantis frogs to have this capability, they hope to learn whether they retained it from an ancestor while relatives did not, or whether the trait evolved independently in each species.

Golden frog of Panama and its skin microbiome

Caption: Researchers studied microbial communities on the skin of Panamanian golden frogs to learn more about amphibian disease resistance. Panamanian golden frogs live only in captivity. Continued studies may help restore them back to the wild. Credit: B. Gratwicke/Smithsonian Conservation Biology Institute

Caption: Researchers studied microbial communities on the skin of Panamanian golden frogs to learn more about amphibian disease resistance. Panamanian golden frogs live only in captivity. Continued studies may help restore them back to the wild.
Credit: B. Gratwicke/Smithsonian Conservation Biology Institute

Among many of the pressures on frog populations, there’s a lethal fungus which has affected some 200 species of frogs. A March 23, 2015 news item on ScienceDaily describes some recent research into the bacterial communities present on frog skin,

A team of scientists including Virginia Tech researchers is one step closer to understanding how bacteria on a frog’s skin affects its likelihood of contracting disease.

A frog-killing fungus known as Batrachochytrium dendrobatidis, or Bd, has already led to the decline of more than 200 amphibian species including the now extinct-in-the-wild Panamanian golden frog.

In a recent study, the research team attempted to apply beneficial bacteria found on the skin of various Bd-resistant wild Panamanian frog species to Panamanian golden frogs in captivity, to see if this would stimulate a defense against the disease.

A March 23, 2015 Virginia Tech University news release on EurekAlert, which originated the news item, provides a twist and a turn in the story (Note: Links have been removed),

They found that while the treatment with beneficial bacteria was not successful due to its inability to stick to the skin, there were some frogs that survived exposure to the fungus.

These survivors actually had unique bacterial communities on their skin before the experiments started.

The next step is to explore these new bacterial communities.

“We were disappointed that the treatment didn’t work, but glad to have discovered new information about the relationship between these symbiotic microbial communities and amphibian disease resistance,” said Lisa Belden, an associate professor of biological sciences in the College of Science, a Fralin Life Science Institute affiliate, and a faculty member with the new Global Change Center at Virginia Tech. “Every bit of information gets us closer to getting these frogs back into nature.”

Studying the microbial communities of Panamanian golden frogs was the dissertation focus of Belden’s former graduate student Matthew Becker, who graduated with a Ph.D. in biological sciences from Virginia Tech in 2014 and is now a fellow at the Smithsonian Conservation Biology Institute.

“Anything that can help us predict resistance to this disease is very useful because the ultimate goal of this research is to establish healthy populations of golden frogs in their native habitat,” Becker told Smithsonian Science News. “I think identifying alternative probiotic treatment methods that optimize dosages and exposure times will be key for moving forward with the use of probiotics to mitigate chytridiomycosis.”

Here’s a link to and a citation for the paper,

Composition of symbiotic bacteria predicts survival in Panamanian golden frogs infected with a lethal fungus by Matthew H. Becker , Jenifer B. Walke , Shawna Cikanek , Anna E. Savage , Nichole Mattheus , Celina N. Santiago , Kevin P. C. Minbiole , Reid N. Harris , Lisa K. Belden , Brian Gratwicke. April 2015 Volume: 282 Issue: 1805 DOI: 10.1098/rspb.2014.2881 Published 18 March 2015

This is an open access paper.

For anyone curious about the article in the Smithsonian mentioned in the news release, you can find it here.

 

Dancing droplets—a mystery solved

I love simple yet profound discoveries like the one described in a March 12, 2015 news item on Nanowerk (Note: A link has been removed),

 A puzzling observation, pursued through hundreds of experiments, has led Stanford researchers to a simple yet profound discovery: under certain circumstances, droplets of fluid will move like performers in a dance choreographed by molecular physics.

“These droplets sense one another. They move and interact, almost like living cells,” said Manu Prakash, an assistant professor of bioengineering and senior author of an article published in Nature (“Vapour-mediated sensing and motility in two-component droplets”).

A March 11, 2015 Stanford University news release by Tom Abate, which originated the news item, describes possible applications and the genesis of this research,

The unexpected findings may prove useful in semiconductor manufacturing and self-cleaning solar panels, but what truly excites Prakash is that the discovery resulted from years of persistent effort to satisfy a scientific curiosity.

The research began in 2009 when Nate Cira, then an undergraduate at the University of Wisconsin, was doing an unrelated experiment. In the course of that experiment Cira deposited several droplets of food coloring onto a sterilized glass slide and was astonished when they began to move.

Here’s a video of the researchers discussing their work and their findings (Video by Kurt Hickman),

The news release elaborates,

Together they spent three years performing increasingly refined experiments to learn how these tiny droplets of food coloring sense one another and move. In living cells these processes of sensing and motility are known as chemotaxis.

“We’ve discovered how droplets can exhibit behaviors akin to artificial chemotaxis,” Prakash said.

As the Nature article explains, the critical fact was that food coloring is a two-component fluid. In such fluids, two different chemical compounds coexist while retaining separate molecular identities

The droplets in this experiment consisted of two molecular compounds found naturally in food coloring: water and propylene glycol.

The researchers discovered how the dynamic interactions of these two molecular components enabled inanimate droplets to mimic some of the behaviors of living cells.

Surface tension and evaporation

Essentially, the droplets danced because of a delicate balance between surface tension and evaporation.

Evaporation is easily understood. On the surface of any liquid, some molecules convert to a gaseous state and float away.

Surface tension is what causes liquids to bead up. It arises from how tightly the molecules in a liquid bind together.

Water evaporates more quickly than propylene glycol. Water also has a higher surface tension.  These differences create a tornado-like flow inside the droplets, which not only allows them to move but also allows a single droplet to sense its neighbors.

To understand the molecular forces involved, imagine shrinking down to size and diving inside a droplet.

There, water and propylene glycol molecules try to remain evenly distributed but differences in evaporation and surface tension create turmoil within the droplet.

On the curved dome of each droplet, water molecules become gaseous and float away faster than their evaporation-averse propylene glycol neighbors.

This evaporation happens more readily on the thin lower edges of the domed droplet, leaving excess of propylene glycol there. Meanwhile, the peak of the dome has a higher concentration of water.

The water at the top exerts its higher surface tension to pull the droplet tight so it doesn’t flatten out. This tugging causes a tumbling molecular motion inside the droplet. Thus surface tension gets the droplet ready to roll.

Evaporation determines the direction of that motion. Each droplet sends aloft gaseous molecules of water like a radially emanating signal announcing the exact location of any given droplet. The droplets converge where the signal is strongest.

So evaporation provided the sensing mechanism and surface tension the pull to move droplets together in what seemed to the eye to be a careful dance.

Rule for two-component fluids

The researchers experimented with varied proportions of water and propylene glycol. Droplets that were 1 percent propylene glycol (PG) to 99 percent water exhibited much the same behavior as droplets that were two-thirds PG to just one-third water.

Based on these experiments the paper describes a “universal rule” to identify any two-component fluids that will demonstrate sensing and motility.

Adding colors to the mixtures made it easier to tell how the droplets of different concentrations behaved and created some visually striking results.

In one experiment, a droplet with more propylene glycol seems to chase a droplet with more water. In actuality, the droplet with more water exerts a higher surface tension tug, pulling the propylene droplet along.

In another experiment, researchers showed how physically separated droplets could align themselves using ever-so-slight signals of evaporation.

In a third experiment they used Sharpie pens to draw black lines on glass slides. The lines changed the surface of the slide and created a series of catch basins. The researchers filled each basin with fluids of different concentrations to create a self-sorting mechanism. Droplets bounced from reservoir to reservoir until they sensed the fluid that matched their concentration and merged with that pool.

What started as a curiosity-driven project may also have many practical implications.

The deep physical understanding of two component fluids allows the researchers to predict which fluids and surfaces will show these unusual effects. The effect is present on a large number of common surfaces and can be replicated with a number of chemical compounds.

Here’s a link to and a citation for the paper,

Vapour-mediated sensing and motility in two-component droplets by N. J. Cira, A. Benusiglio, & M. Prakash. Nature  (2015) doi:10.1038/nature14272 Published online 11 March 2015

This paper is behind a paywall.

Making x-ray measurements more accurate

Apparently the method for establishing x-ray measurements is from the 1970s and the folks at the US National Institute of Standards and Technology (NIST) feel it’s time for a new technique. From a March 9, 2015 NIST news release (also on EurekAlert),

Criminal justice, cosmology and computer manufacturing may not look to have much in common, but these and many other disparate fields all depend on sensitive measurements of X-rays. Scientists at the National Institute of Standards and Technology (NIST) have developed a new method* to reduce uncertainty in X-ray wavelength measurement that could provide improvements awaited for decades.

Accurate measurement of X-ray wavelengths depends critically on the ability to measure angles very precisely and with very little margin for error. NIST’s new approach is the first major advance since the 1970s in reducing certain sources of error common in X-ray angle measurement.

Many of us associate X-rays with a doctor’s office, but the uses for these energetic beams go far beyond revealing our skeletons. The ability to sense X-rays at precise wavelengths allows law enforcement to detect and identify trace explosives, or astrophysicists to better understand cosmic phenomena. It all comes down to looking very closely at the X-ray spectrum and measuring the precise position of lines within it. Those lines represent specific wavelengths–which are associated with specific energies–of X-rays that are emitted by the subject being studied. Each material has its own, unique X-ray “fingerprint.”

But a slight error in angle measurement can skew the results, with consequences for quantum theories, research and manufacturing. “While many fields need good X-ray reference data, many of the measurements that presently fill standard reference databases are not great–most data were taken in the 1970s and are often imprecise,” says NIST’s Larry Hudson.

X-ray wavelengths are measured by passing the beam through special crystals and very carefully measuring the angle that exiting rays make with the original beam. While the physics is different, the technique is analogous to the way a prism will split white light into different colors coming out at different angles.

The crystal is typically mounted on a rotating device that spins the crystal to two different positions where a spectral line is observed. The angle between the two is measured–this is a neat geometry trick that determines the line’s position more precisely than a single measurement would, while also cancelling out some potential errors. One inevitable limit is the accuracy of the digital encoder, the device that translates the rotation of the crystal to an angle measurement.

The news release goes on to describe the new technique,

Hudson and his co-authors have found a way to dramatically reduce the error in that measurement. Their new approach uses laser beams bouncing off a mirrored polygon that is rotated on the same shaft that would carry the crystal. The approach allows the team to use additional mathematical shortcuts to their advantage. With new NIST sensing instrumentation and analysis, X-ray angles can now be measured routinely with an uncertainty of 0.06 arcseconds–an accuracy more than three times better than the uncalibrated encoder.

Hudson describes this reduction as significant enough to set world records in X-ray wavelength measurement. “If a giant windshield wiper stretched from Washington D.C. to New York City (364 kilometers) and were to sweep out the angle of one of these errors, its tip would move less than the width of a DVD,” he says.

What do these improvements mean for the fields that depend on X-ray sensing? For one thing, calibrating measurement devices to greater precision will provide better understanding of a host of newly designed materials, which often have complicated crystal structures that give rise to unusual effects such as high-temperature superconductivity. The team’s efforts will permit better understanding of the relationship between the structures and properties of novel materials.

Here’s a link to and a citation for the paper,

A simple method for high-precision calibration of long-range errors in an angle encoder using an electronic nulling by Mark N Kinnane, Lawrence T Hudson, Albert Henins, and Marcus H Mendenhall. Metrologia Volume 52 Number 2 doi:10.1088/0026-1394/52/2/244

This is an open access paper,

For anyone curious about arcseconds, you can find an explanation in this Wikipedia entry titled Minute of art. Briefly, imagine a 360 degree circle where one degree equals one arcminute and one arcsecond is 1/60 of that minute.

Capturing the particle and the wave: photographing light

On returning to school to get a bachelor’s degree, I registered in a communications course and my first paper was about science, light, and communication. The particle/wave situation still fascinates me (and I imagine many others).

A March 2, 2015 news item on phys.org describes the first successful photography of light as both particle and wave,

Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time. Now, scientists at EPFL [École polytechnique fédérale de Lausanne in Switzerland] have succeeded in capturing the first-ever snapshot of this dual behavior.

Quantum mechanics tells us that light can behave simultaneously as a particle or a wave. However, there has never been an experiment able to capture both natures of light at the same time; the closest we have come is seeing either wave or particle, but always at different times. Taking a radically different experimental approach, EPFL scientists have now been able to take the first ever snapshot of light behaving both as a wave and as a particle. The breakthrough work is published in Nature Communications.

A March 2, 2015 EPFL press release (also on EurekAlert), which originated the news item, describes the science and the research,

When UV light hits a metal surface, it causes an emission of electrons. Albert Einstein explained this “photoelectric” effect by proposing that light – thought to only be a wave – is also a stream of particles. Even though a variety of experiments have successfully observed both the particle- and wave-like behaviors of light, they have never been able to observe both at the same time.

A research team led by Fabrizio Carbone at EPFL has now carried out an experiment with a clever twist: using electrons to image light. The researchers have captured, for the first time ever, a single snapshot of light behaving simultaneously as both a wave and a stream of particles particle.

The experiment is set up like this: A pulse of laser light is fired at a tiny metallic nanowire. The laser adds energy to the charged particles in the nanowire, causing them to vibrate. Light travels along this tiny wire in two possible directions, like cars on a highway. When waves traveling in opposite directions meet each other they form a new wave that looks like it is standing in place. Here, this standing wave becomes the source of light for the experiment, radiating around the nanowire.

This is where the experiment’s trick comes in: The scientists shot a stream of electrons close to the nanowire, using them to image the standing wave of light. As the electrons interacted with the confined light on the nanowire, they either sped up or slowed down. Using the ultrafast microscope to image the position where this change in speed occurred, Carbone’s team could now visualize the standing wave, which acts as a fingerprint of the wave-nature of light.

While this phenomenon shows the wave-like nature of light, it simultaneously demonstrated its particle aspect as well. As the electrons pass close to the standing wave of light, they “hit” the light’s particles, the photons. As mentioned above, this affects their speed, making them move faster or slower. This change in speed appears as an exchange of energy “packets” (quanta) between electrons and photons. The very occurrence of these energy packets shows that the light on the nanowire behaves as a particle.

“This experiment demonstrates that, for the first time ever, we can film quantum mechanics – and its paradoxical nature – directly,” says Fabrizio Carbone. In addition, the importance of this pioneering work can extend beyond fundamental science and to future technologies. As Carbone explains: “Being able to image and control quantum phenomena at the nanometer scale like this opens up a new route towards quantum computing.”

This work represents a collaboration between the Laboratory for Ultrafast Microscopy and Electron Scattering of EPFL, the Department of Physics of Trinity College (US) and the Physical and Life Sciences Directorate of the Lawrence Livermore National Laboratory. The imaging was carried out EPFL’s ultrafast energy-filtered transmission electron microscope – one of the two in the world.

For anyone who prefers videos, the EPFL researchers have  prepared a brief description (loaded with some amusing images) of their work,


Here’s a link to and a citation for the research paper,

Simultaneous observation of the quantization and the interference pattern of a plasmonic near-field by L Piazza, T.T.A. Lummen, E Quiñonez, Y Murooka, B.W. Reed, B Barwick & F Carbone. Nature Communications 6, Article number: 6407 doi:10.1038/ncomms7407 Published 02 March 2015

This is an open access paper.

Hydrogels and cartilage; repurposing vehicles in space; big bang has ‘fingerprints’

The American Institute of Physics (AIP) has made a selection of four articles freely available (h/t Mar. 9, 2015 news item on Azonano).

From a March 6, 2015 AIP news release,

WASHINGTON D.C., March 6, 2015 — The following articles are freely available online from Physics Today (www.physicstoday.org), the world’s most influential and closely followed magazine devoted to physics and the physical science community.

You are invited to read, share, blog about, link to, or otherwise enjoy:

1) STIFF AND SUPPLE CARTILAGE SUBSTITUTE

Physics Today‘s Ashley Smart reports on hydrogels that mimic the tricky nature of cartilage thanks to magnetically aligned nanosheets.

“In the realm of bioengineering, hydrogels are something of an all-purpose material. Made up of networks of interlinked, hydrophilic polymers, they tend to be soft, biocompatible, and highly absorbent…. The new material mimics the articular cartilage that lubricates our joints: It can support a heavy load along one direction while stretching and shearing with ease in the others.”

MORE: http://dx.doi.org/10.1063/PT.3.2707

2) GIVING SPACECRAFT A SECOND LEASE ON LIFE WHILE HURTLING THROUGH THE COSMOS

Physics Today‘s Toni Feder reports on the innovative processes undertaken to repurpose various spacecraft in flight, including Kepler, Voyager, Deep Impact, Spitzer, and the Hubble Space Telescope.

“A comeback like Kepler’s is ‘not unique, but it’s unusual,’ says Derek Buzasi of Florida Gulf Coast University, who reinvented the Wide-Field Infrared Explorer (WIRE) after it failed following its 1999 launch. ‘Spacecraft are built for a specialized purpose, so they are hard to repurpose. You have to come up with something they are capable of at the same time they are incapable of their original mission.’

Deep Impact’s original mission was to hurl a copper ball at a comet and watch the impact. In its continued form as EPOXI, the spacecraft went on to visit another comet and, on the way, served as an observatory for user- proposed targets.”

MORE: http://dx.doi.org/10.1063/PT.3.2713

3) CONGRESSMAN & FUSION RESEARCHER REFLECTS ON SCIENCE POLICY

Physics Today‘s David Kramer interviews Rush Holt, the New Jersey congressman who retired from office and this past December took the helm of the American Association for the Advancement of Science.

“PT: What do you consider to be your accomplishments in Congress?

HOLT: I focused a lot on science education. Our real problem is not that we’re failing to produce excellent scientists, because we are [producing them], but rather that we have failed to maintain an appreciation for and understanding of science in the general population. I was able to keep a spotlight on the need but wasn’t able to accomplish as much as I wanted. We got science included in the subjects emphasized by federal law. But we haven’t really improved teacher professional development and other things we need to do.”

MORE: http://dx.doi.org/10.1063/PT.3.2714

4) PARTICLE PHYSICS AND THE COSMIC MICROWAVE BACKGROUND

In this article, physics researchers John Carlstrom, Tom Crawford and Lloyd Knox discuss the fingerprints of the Big Bang and quantum fluctuations in the early universe, which may soon reveal physics at unprecedented energy scales.

“With its empirical successes, inflation is by consensus the best paradigm—notwithstanding some notable dissenting views—for the mechanism that generated the primordial density fluctuations that led to all structure in the universe. Its success has motivated physicists to search for the siblings of those fluctuations, the gravitational waves, via their signature in the polarization of the CMB. If discovered, that gravitational imprint would open up an observational window onto quantum gravitational effects, extremely early times, and extremely high energies.”

MORE: http://dx.doi.org/10.1063/PT.3.2718

I have checked; all of the links do lead to the articles.

International Women’s Day March 8, 2015: Pioneering Women of Physics, Science goes to the Movies, and Transistor

In honour of International Women’s Day 2015, here are four items about women and science. The first features Canada’s Perimeter Institute (PI) and a tribute to pioneering women in physics, from a Feb. 26, 2015 PI news release,

They discovered pulsars, found the first evidence of dark matter, pioneered mathematics, radioactivity, nuclear fission, elasticity, and computer programming, and have even stopped light.

Jocelyn Bell Burnell

Rosalind Franklin

Hedy Lamarr

Wu Chien ShiungIt’s a fascinating group of women and these four provide a taste only.

The second item about women in science is also from the Perimeter Institute, which is hosting an ‘Inspiring Future Women in Science’ conference on Friday, May 6, 2015. From the PI program page,

Are you interested in turning your love of science into a career?  Perimeter Institute is inviting female high school students to participate in an inspirational half day conference on Friday March 6, 2015.  The goal is to bring together like minded young women with a strong interest in science and expose them to the rewards, challenges and possibilities of a career in science.

kEYNOTE ADDRESSES

Rima Brek – Rima is a Ubisoft veteran of 16 years and a founding team member of the Toronto studio. There, she was responsible for kick-starting the technology team and helping ship the critically-acclaimed Tom Clancy’s Splinter Cell Blacklist. She is a sought-after advisor whose guidance and leadership have directly helped Ubisoft Toronto grow to over 300 game developers in just five years.

Dianna Cowern – Dianna is a science communicator and educator. She received her degree in physics from MIT and completed a post-baccalaureate fellowship in astrophysics at Harvard. She then worked on mobile applications as a software engineer at General Electric before beginning a position at the University of California, San Diego as a physics outreach coordinator. She is the primary content creator for her educational YouTube channel, Physics Girl.

Roslyn Bern – As president of the Leacross Foundation, Roslyn Bern has been creating opportunities for women and girls throughout Canada. She has worked on initiatives for over 20 years, as an educator, a business woman, and as a philanthropist. She has focused on developing scholarships and bursaries for girls in under-represented career fields. She has been instrumental on sending teenage girls to the Arctic and Antarctic with Students on Ice, and created a partnership with colleges and corporations to certify STEM women in Electrical engineering. …

By the time this piece is posted it will be too late to attend this year’s event but interested parties could plan for next year in Waterloo, Ontario, Canada.

The third item concerns an initiative from the Public Radio Exchange, PRX. Called Transistor; a STEM [science, technology, engineering, and mathematics] audio project. From the series page,

Transistor is a transformative STEM podcast, taking the electricity of a story and channeling it to listeners. Three scientist hosts — a biologist, an astrophysicist, and a neuroscientist — report on conundrums, curiosities, and current events in and beyond their fields. Sprinkled among their episodes are the winners of the STEM Story Project, a competition we held for unique science radio.

Much as the transistor radio was a new technical leap, this Transistor features new women voices and sounds from new science producers.

PRX presents Transistor, applying our storytelling and podcast experience to science. The Sloan Foundation powers Transistor with funding and support. And listeners complete the circuit.

The Feb. 18, 2015 PRX news release offers more details about the hosts and their first podcasts,

PRX is thrilled to announce the launch of a new weekly podcast series Transistor (official press release). Three scientist hosts — a biologist, an astrophysicist, and a neuroscientist — report on conundrums, curiosities, and current events in and beyond their fields. Sprinkled among their episodes are the winners of the PRX STEM Story Project, a competition we held for unique science radio.

Just as the transistor radio was a new technical leap, this Transistor features new women voices and their science perspectives. We’ve launched with four episodes from our three scientist hosts:

  • Dr. Michelle Thaller, an astrophysicist at NASA’s Goddard Space Flight Center, who studies binary stars and the life cycles of the stars.
    • We Are Stardust: We’re closer than ever before to discovering if we’re not alone in the universe. Astrophysicist Michelle Thaller visits the NASA lab that discovered that comets contain some of the very same chemical elements that we contain. Then, Michelle talks to a Vatican planetary scientist about how science and religion can meet on the topic of life beyond Earth.
  • Dr. Christina Agapakis, a biologist and writer based in Los Angeles. Her research focuses on the intersection of microbiology and design, exploring the symbiosis among microbes and biology, technology, and culture.
    • Food, Meet Fungus: The microbiome — the trillions of bacteria, fungi, and viruses that live in and on our body — is hot right now. We explore what we do know in the face of so much hope and hype, starting with food.
  • Dr. Wendy Suzuki, a Professor of Neural Science and Psychology in the Center for Neural Science at New York University, whose research focuses on understanding how our brains form and retain new long-term memories and the effects of aerobic exercise on memory. Her book Healthy Brain, Happy Life will be published by Harper Collins in the Spring of 2015.
    • Totally Cerebral: Untangling the Mystery of Memory: Neuroscientist Wendy Suzuki introduces us to scientists who have uncovered some of the deepest secrets about our brains. She begins by talking with experimental psychologist Brenda Milner [interviewed in her office at McGill University, Montréal, Quebéc], who in the 1950s, completely changed our understanding of the parts of the brain important for forming new long-term memories.
    • Totally Cerebral: The Man Without a Memory: Imagine never being able to form a new long term memory after the age of 27. Welcome to the life of the famous amnesic patient “HM”. Neuroscientist Suzanne Corkin studied HM for almost half a century, and gives us a glimpse of what daily life was like for him, and his tremendous contribution to our understanding of how our memories work.

Each scientist is working with a talented independent producer: Lauren Ober, Julie Burstein, and Kerry Donahue.

Subscribe to the show through iTunes or RSS, or you can stream it on PRX.org.

I listened to all four of the introductory programs which ranged in running time from about 16 mins. to 37 mins. All three hosts are obviously excited about sharing their science stories and I look forward to hearing more from them.

The last item comes from David Bruggeman’s Feb. 20, 2015 post on his Pasco Phronesis blog (Note: A link has been removed),

Science Goes to the Movies is a new program produced by the City University of New York and sponsored by the Alfred P. Sloan Foundation. … The hosts are Faith Salie, a journalist and host you might have heard before as a panelist on Wait Wait…Don’t Tell Me, and Dr. Heather Berlin, a neuroscientist whose research focuses on brain-body relationships and psychological disorders.  (In what makes for a small world, Berlin is married to Canadian rap troubadour Baba Brinkman.) …

Science Goes to the Movies can be found here where you’ll also find a video of the first episode,

Hallucinations and black holes vie for the 2015 Oscar. Co-hosts Faith Salie and Dr. Heather Berlin are joined by AMNH astrophysicist Dr. Emily Rice for a look at the science in three of the top films of the year, Birdman, The Theory of Everything, and Interstellar.

Episode 102 featuring Into the Woods and the Imitation Game will première on March 20, 2015,

Science Goes to the Movies looks at The Imitation Game and Into the Woods. With special guest cryptologist Rosario Gennaro, we discuss pattern recognition in the work of both Alan Turing and Stephen Sondheim.

Science Goes to the Movies is made possible by generous support from the Alfred P. Sloan Foundation.

Kudos to the Alfred P. Sloan foundation for funding two exciting ventures: Transistors and Science Goes to the Movies.

Getting back to where I started: Happy International Women’s Day 2015!

Medical isotope team at TRIUMF (Canada’s national laboratory for particle and nuclear physics) wins award

I’ve written a few times about the development of a new means for producing medical isotopes that does not require nuclear materials. (my June 10, 2014 posting and my June 9, 2013 posting,) The breakthrough was made at TRIUMF, Canada’s national laboratory for particle and nuclear physics, which is located in Vancouver, and the team which made the breakthrough is being honoured. From a Feb. 17, 2015 TRIUMF news release,

For their outstanding teamwork in realizing a solution for safe and reliable isotope production for hospitals in Canada,interdisciplinary research team CycloMed99 will be receiving a prestigious national award at a ceremony in Ottawa today [Feb. 17, 2015]. The Honourable David Johnston, Governor General of Canada, will present the NSERC  [Natural Sciences and Engineering Research Council of Canada] Brockhouse Canada Prize for Interdisciplinary Research in Science and Engineering to the team in recognition of their seamless teamwork and successes.

Drawing from expertise in physics, chemistry, and nuclear medicine, the team set out five years ago to develop a reliable, alternative means of production for a key medical isotope in order to eliminate the threat of a supply shortage – a catastrophic healthcare crisis for patients around the world. Technetium-99m (Tc-99m) is the world standard for medical imaging to diagnose cancer and heart disease. Every day, 5,000 medical procedures in
Canada and 70,000 daily worldwide depend on this isotope. With funding support from NSERC, CIHR and Natural Resources Canada, the team developed technology that uses medical cyclotrons already installed and operational in major hospitals across Canada to produce enough Tc-99m on a daily basis.

This innovation is safer and more environmentally friendly than current technology because it eliminates the need for highly enriched uranium, also avoiding the generation
of highly radioactive waste. Canada’s healthcare system would save money by producing isotopes locally under a full-cost recovery model.

The project resulted in over a dozen scientific publications, several provisional patents and a training opportunity for more than 175 individuals.

Now, the research team is focused on working with the world’s major cyclotron manufacturers to add factory-supported Tc-99m production capability to their existing product lines so the technology will become standard in future machines.

CycloMed99 is also working with a Canadian start-up company to license, transfer and sell this technology around the world. This will allow hospitals and companies with cyclotrons to retrofit their existing infrastructure with a Made in Canada solution to produce this valuable material.

Congratulations to the CycloMed99 team, recipients of the Brockhouse Canada Prize:

• Dr. Paul Schaffer, a chemist by training and Division Head, Nuclear Medicine at TRIUMF; Adjunct Professor, Dept. of Chemistry at Simon Fraser University; and Professor, Dept. of Radiology at the University of British Columbia (UBC);

• Dr. François Bénard, a clinician by training and BC Leadership Chair in Functional Cancer Imaging at the BC Cancer Agency; and Professor, Dept. of Radiology at UBC;

• Dr. Anna Celler, a medical physicist by training and Professor, Dept. of Radiology at UBC;

• Dr. Michael Kovacs, a chemist by training; PET Radiochemistry Facility Imaging Scientist at Lawson Health Research Institute; Associate Professor at Western University;

• Dr. Thomas J. Ruth, a nuclear chemist by training and researcher emeritus at TRIUMF; and Professor emeritus at UBC, and;

• Dr. John Valliant, a chemist by training and Scientific Director and CEO of the Centre for Probe Development and Commercialization; and Professor at McMaster University.

There’s more information about TRIUMF and the business aspect of this breakthrough in a Jan. 16, 2015 article by Tyler Orton for Business in Vancouver.

The birth of a molecule

This research comes from Korea’s Institute of Basic Science in a Feb. 27, 2015 news item on Azonano,

The research team of the Center for Nanomaterials and Chemical Reactions at the Institute for Basic Science (IBS) has successfully visualized the entire process of bond formation in solution by using femtosecond time-resolved X-ray liquidography (femtosecond TRXL) for the first time in the world.

A Feb. 18, 2015 IBS press release, which originated the news item, provides more details,

Every researcher’s longstanding dream to observe real-time bond formation in chemical reactions has come true. Since this formation takes less than one picosecond, researchers have not been able to visualize the birth of molecules.

The research team has used femtosecond TRXL in order to visualize the formation of a gold trimer complex in real time without being limited by slow diffusion.

They have focused on the process of photoinduced bond formation between gold (Au) atoms dissolved in water. In the ground (S0) state, Au atoms are weakly bound to each other in a bent geometry by van der Waals interactions. On photoexcitation, the S0 state rapidly converts into an excited (S1) state, leading to the formation of covalent Au-Au bonds and bent-to-linear transition. Then, the S1 state changes to a triplet (T1) state with a time constant of 1.6 picosecond, accompanying further bond contraction by 0.1 Å. Later, the T1 state of the trimer transforms to a tetramer on nanosecond time scale, and Au atoms return to their original bent structure.

“By using femtosecond TRXL, we will be able to observe molecular vibration and rotation in the solution phase in real time,” says Hyotcherl Ihee, the group leader of the Center for Nanomaterials at IBS, as well as the professor of the Department of Chemistry at Korea Advanced Institute of Science and Technology.

Here’s a link to and a citation for the paper,

Direct observation of bond formation in solution with femtosecond X-ray scattering by Kyung Hwan Kim, Jong Goo Kim, Shunsuke Nozawa, Tokushi Sato, Key Young Oang, Tae Wu Kim, Hosung Ki, Junbeom Jo, Sungjun Park, Changyong Song, Takahiro Sato, Kanade Ogawa, Tadashi Togashi, Kensuke Tono, Makina Yabashi, Tetsuya Ishikawa, Joonghan Kim, Ryong Ryoo, Jeongho Kim, Hyotcherl Ihee & Shin-ichi Adachi. Nature 518, 385–389 (19 February 2015) doi:10.1038/nature14163 Published online 18 February 2015

This paper is behind a paywall although there is a free preview via ReadCube access.

LaBiotechMap (a map of European biotechnology companies)

Thanks to Joachim Eeckhout of the LaBiotechMap team for contacting me regarding his and co-founder Philip Hemme’s European  biotechnology company map.

You can find the map here and for those who need an incentive to explore, here’s a bit of information and a few images from the site’s homepage to whet your interest,

It’s Elegant.

We spent time designing the map. And it’s apparent. Benefit from its unique user experience and finally enjoy surfing through Biotech companies.

It’s Focused.

Instead of gathering the universe of Biotech companies, we offer you a pre-selected galaxy. It results in the most coherent European Biotech Database.

It’s Smart.

Weekly updated, to keep you on track. Searchable, to directly reach your target. Sortable, for high precision.
In a word: Smart.

Here’s a screen capture or representation of the map,

LaBiotechMap

Here’s a screen capture or representation of the database search,

LaBiotechDatabase

Here’s more about the project from the FAQ (frequently asked questions) page,

What is our definition of a Biotech company?

Biotech is certainly one of the most difficult technological term to define.

For us, Biotech is not all life sciences, neither beer or cheese manufacturing. The gene editing revolution of the 80s gave birth to the term Biotechnology and is linked to the foundation of Genentech in California. Today, Biotechnology have a significant impact on the World by helping cure, feed and fuel people. Ground-breaking technologies includes for example gene therapy, biofuels, monoclonal antibodies, cell therapy and GMOs.

Which are our selection criteria?

Our selection criteria to enter for free on the map is to have raised or generated over €1M and to be innovative (spending high % of revenues in R&D and owning patents).

Can you help us improving it?

Yes, everybody can participate. You saw a company missing, a wrong information, an old information or something else? You can use our feedback page or send us a mail to contact-at-labiotechmap.com

Can people stop getting bored by surfing through Biotech companies?

We hope so.

Can I share the map if I like it?

We hope so.

They have a company blog on the website which doesn’t include any dates on the posts (sigh) but I believe their mention of launching the final version of the map in Munich (Munchen, Germany) is relatively recent,

Here we go, we launched the final version of LaBiotech Map in Munich in front of 30 CEOs during a brunch organized by the IZB cluster.

Creating a European Biotech Map may sound crazy, but we like challenges. We started working on it in September 2014 and launched a beta version beginning of November. Within 3 months, we received over 100 exciting feedback and more than 2000 people tried it out. …

I wish the founders and their team good luck with visualizing the biotech company scene in Europe.

Final note: this is not the only European map of its kind, there’s also France’s interactive nanotechnology map featured in my Feb. 4, 2013 posting.

Gender gaps in science and how statistics prove and disprove the finding

A Feb. 17, 2015 Northwestern University news release by Hilary Hurd Anyaso (also on EurekAlert) features research suggesting that parity in the numbers of men and women students pursuing science degrees is being achieved,

Scholars from diverse fields have long proposed that interlocking factors such as cognitive abilities, discrimination and interests may cause more women than men to leave the science, technology, engineering and mathematics (STEM) pipeline after entering college.

Now a new Northwestern University analysis has poked holes in the much referenced “leaky pipeline” metaphor.

The research shows that the bachelor’s-to-Ph.D. pipeline in science and engineering fields no longer leaks more women than men as it did in the past

Curt Rice, a professor at Norway’s University of Tromsø, has challenged the findings in a Feb. 18, 2015 post on his eponymous website (more about that later).

The news release goes on to describe how the research was conducted and the conclusions researchers drew from the data,

The researchers used data from two large nationally representative research samples to reconstruct a 30-year portrait of how bachelor’s-to-Ph.D. persistence rates for men and women have changed in the United States since the 1970s. For this study, the term STEM persistence rate refers to the proportion of students who earned a Ph.D. in a particular STEM field (e.g. engineering) among students who had earlier received bachelor’s degrees in that same field.

They were particularly surprised that the gender persistence gap completely closed in pSTEM fields (physical science, technology, engineering and mathematics) — the fields in which women are most underrepresented.

Among students earning pSTEM bachelor’s degrees in the 1970s, men were 1.6 to 1.7 times as likely as women to later earn a pSTEM Ph.D. However, this gap completely closed by the 1990s.

Men still outnumber women by approximately three to one among pSTEM Ph.D. earners. But those differences in representation are not explained by differences in persistence from the bachelor’s to Ph.D. degree, said David Miller, an advanced doctoral student in psychology at Northwestern and lead author of the study.

“Our analysis shows that women are overcoming any potential gender biases that may exist in graduate school or undergraduate mentoring about pursing graduate school,” Miller said. “In fact, the percentage of women among pSTEM degree earners is now higher at the Ph.D. level than at the bachelor’s, 27 percent versus 25 percent.”

Jonathan Wai, a Duke University Talent Identification Program research scientist and co-author of the study, said a narrowing of gender gaps makes sense given increased efforts to promote gender diversity in science and engineering.

“But a complete closing of the gap was unexpected, especially given recent evidence of gender bias in science mentoring,” Wai said.

Consequently, the widely used leaky pipeline metaphor is a dated description of gender differences in postsecondary STEM education, Wai added.

Other research shows that gaps in persistence rates are also small to nonexistent past the Ph.D., Miller said.

“For instance, in physical science and engineering fields, male and female Ph.D. holders are equally likely to earn assistant professorships and academic tenure,” Miller said.

The leaky pipeline metaphor is inaccurate for nearly all postsecondary pathways in STEM, Miller said, with two important exceptions.

“The Ph.D.-to-assistant-professor pipeline leaks more women than men in life science and economics,” he said. “Differences in those fields are large and important.”

The implications of the research, Miller said, are important in guiding research, resources and strategies to explain and change gender imbalances in science.

“The leaking pipeline metaphor could potentially direct thought and resources away from other strategies that could more potently increase women’s representation in STEM,” he said.

For instance, plugging leaks in the pipeline from the beginning of college to the bachelor’s degree would fail to substantially increase women’s representation among U.S. undergraduates in the pSTEM fields, Miller said.

Of concern, women’s representation among pSTEM bachelor’s degrees has been decreasing during the past decade, Miller noted. “Our analyses indicate that women’s representation at the Ph.D. level is starting to follow suit by declining for the first time in over 40 years,” he said.

“This recent decline at the Ph.D. level could likely mean that women’s progress at the assistant professor level might also slow down or reverse in future years, so these trends will need to be watched closely,” Wai said.

While the researchers are encouraged that gender gaps in doctoral persistence have closed, they stressed that accurately assessing and changing gender biases in science should remain an important goal for educators and policy makers.

Before moving on to Rice’s comments, here’s a link to and citation for the paper,

The bachelor’s to Ph.D. STEM pipeline no longer leaks more women than men: a 30-year analysis by David I. Miller and Jonathan Wai. Front. Psychol., 17 February 2015, doi: 10.3389/fpsyg.2015.00037

This paper is open access (at least for now).

Maybe the situation isn’t improving after all

Curt Rice’s response titled, The incontinent pipeline: it’s not just women leaving higher education, suggests this latest research has unmasked a problem (Note: Links have been removed),

Freshly published research gives a more nuanced picture. The traditional recitation of percentages at various points along the pipeline provides a snapshot. The new research is more like a time-lapse film.

Unfortunately, the new study doesn’t actually show a pipeline being tightened up to leak less. Instead, it shows a pipeline that is leaking even more! The convergence in persistence rates for men and women is not a result of an increase in the rate of women taking a PhD; it’s the result of a decline in the rate of men doing so. It’s as though the holes have gotten bigger — they used to be so small that only women slipped through, but now men slide out, too.

Rice believes  that this improvement is ‘relative improvement’ i.e. the improvement exists in relation to declining numbers of men, a statistic that Rice gives more weight to than the Northwestern researchers appear to have done. ‘Absolute improvement’ would mean that numbers of women studying in the field had improved while men’s numbers had held steady or improved for them too.

To be fair, the authors of the paper seem to have taken at least some of this decline in men’s numbers into account (from the research paper),,

Reasons for the convergences in persistence rates remain unclear. Sometimes the convergence was driven by declines in men’s rates (e.g., in mathematics/computer science), increases in women’s rates (e.g., in physical science), or both (e.g., in engineering). help account for the changes in persistence rates. …

Overenthusiasm in the news release

Unfortunately, the headline and bullet list of highlights suggest a more ebullient research conclusion than seems warranted by the actual research results.

Think again about gender gap in science
Bachelor’s-to-Ph.D. pipeline in science, engineering no longer ‘leaks’ more women than men, new 30-year analysis finds

Research shows dated ‘leaky pipeline’ assumptions about gender imbalances in science

  • Men outnumber women as Ph.D. earners in science but no longer in doctoral persistence
  • Dramatic increase of women in science at Ph.D., assistant professorship levels since 1970s, but recent decline since 2010 may be of concern for future supply of female scientists
  • Assessing inaccurate assumptions key to correcting gender biases in science

Here’s the researchers’ conclusion,

Overall, these results and supporting literature point to the need to understand gender differences at the bachelor’s level and below to understand women’s representation in STEM at the Ph.D. level and above. Women’s representation in computer science, engineering, and physical science (pSTEM) fields has been decreasing at the bachelor’s level during the past decade. Our analyses indicate that women’s representation at the Ph.D. level is starting to follow suit by declining for the first time in over 40 years (Figure 2). This recent decline may also cause women’s gains at the assistant professor level and beyond to also slow down or reverse in the next few years. Fortunately, however, pathways for entering STEM are considerably diverse at the bachelor’s level and below. For instance, our prior research indicates that undergraduates who join STEM from a non-STEM field can substantially help the U.S. meet needs for more well-trained STEM graduates (Miller et al., under review). Addressing gender differences at the bachelor’s level could have potent effects at the Ph.D. level, especially now that women and men are equally likely to later earn STEM Ph.D.’s after the bachelor’s.

The conclusion seems to contradict the researchers’ statements in the news release,

“But a complete closing of the gap was unexpected, especially given recent evidence of gender bias in science mentoring,” Wai said.

Consequently, the widely used leaky pipeline metaphor is a dated description of gender differences in postsecondary STEM education, Wai added.

Other research shows that gaps in persistence rates are also small to nonexistent past the Ph.D., Miller said.

Incomplete pipeline

Getting back to Rice, he notes the pipeline in the Northwestern paper is incomplete (Note: Links have been removed),

In addition to the dubious celebration of the decline of persistence rates of men, the new research article also looks at an incomplete pipeline. In particular, it leaves aside the important issue of which PhD institutions students get into. For young researchers moving towards academic careers, we know that a few high-prestige universities are responsible for training future faculty members at nearly all other research universities. Are women and men getting into those high prestige universities in the same numbers? Or do women go to lower prestige institutions?

Following on that thought about lower prestige institutions and their impact on your career, there’s a Feb. 23, 2015 article by Joel Warner and Aaron Clauset in Slate investigating the situation, which applies to both men and women,

The United States prides itself on offering broad access to higher education, and thanks to merit-based admissions, ample financial aid, and emphasis on diverse student bodies, our country can claim some success in realizing this ideal.

The situation for aspiring professors is far grimmer. Aaron Clauset, a co-author of this article, is the lead author of a new study published in Science Advances that scrutinized more than 16,000 faculty members in the fields of business, computer science, and history at 242 schools. He and his colleagues found, as the paper puts it, a “steeply hierarchical structure that reflects profound social inequality.” The data revealed that just a quarter of all universities account for 71 to 86 percent of all tenure-track faculty in the U.S. and Canada in these three fields. Just 18 elite universities produce half of all computer science professors, 16 schools produce half of all business professors, and eight schools account for half of all history professors.

Then, Warner and Clauset said this about gender bias,

Here’s further evidence that the current system isn’t merely sorting the best of the best from the merely good. Female graduates of elite institutions tend to slip 15 percent further down the academic hierarchy than do men from the same institutions, evidence of gender bias to go along with the bias toward the top schools.

I suggest reading the Slate article, Rice’s post, and, if you have time, the Northwestern University research paper.

Coda: All about Curt Rice

Finally, this is for anyone who’s unfamiliar with Curt Rice (from the About page on his website; Note: Links have been removed),

In addition to my work as a professor at the University of Tromsø, I have three other roles that are closely related to the content on this website. I was elected by the permanent faculty to sit on the university board, I lead Norway’s Committee on Gender Balance and Diversity in Research, and I am the head of the Board for Current Research Information System in Norway (CRIStin). In all of these roles, I work to pursue my conviction that research and education are essential to improving society, and that making universities better therefore has the potential to make societies better.

I’m currently writing a book on gender balance. Why do men and women have different career paths? Why should we care? How can we start to make things better? Why is improving gender balance not only the right thing to do, but also the smart thing to do? For a taste of my approach, grab a copy of my free ebook on gender equality.

Beyond this book project, I use my speaking and writing engagements to reach audiences on the topics that excite me the most: gender balance, open access, leadership issues and more. These interests have grown during the past decade while I’ve had the privilege to occupy what were then two brand new leadership positions at the University of Tromsø.

From 2009–2013, I served as the elected Vice Rector for Research & Development (prorektor for forskning og utvikling). Before that, from 2002–2008, I was the founding director of my university’s first Norwegian Center of Excellence, the Center for Advanced Study in Theoretical Linguistics (CASTL). Given the luxury of being able to define those positions, I was able to pursue my passion for improving academic life by working to enhance conditions for education and research.

I’m part of the European Science Foundation’s genderSTE COST action (Gender, Science, Technology and Environment); I helped create the BALANSE program at the Research Council of Norway, which is designed to increase the numbers of women at the highest levels of research organizations. I am on the Advisory Board of the European Commission project EGERA (Effective Gender Equality in Research and Academia); I was on the Science Leaders Panel of the genSET project, in which we advised the European Commission about gender in science; I am a member of the Steering Committee for the Gender Summits.

I also led a national task force on research-based education that issued many suggestions for Norwegian institutions.