Sandcastles of Stars Make Stable Structures

Sandcastles are not known for their structural stability; even the most steadfast seaside fortresses won’t survive a crashing wave or a bully’s kick.

But what if, instead of round grains of sand, you built your castle from tiny stars?

Duke graduate student Yuchen Zhao tests the stability of a tower made from six-armed stars or “hexapods.”

Duke graduate student Yuchen Zhao has spent the last year studying such “sandcastles of stars” — towers crafted from hundreds of six-armed stars or “hexapods” which bear a remarkable resemblance to the jacks you might have played with as a kid.

To build these towers, Zhao simply pours the stars into a hollow tube, and then removes the tube. But unlike columns of sand, these towers stand on their own, stay up when shaken, and can even bear up to twice their own weight.

“When you remove the support, you see that the star particles have really jammed together!” said Zhao. “Nobody understands exactly how this rigidity comes about.”

Sand is a classic example of a granular material, and like other types of granular materials — rice, flour, marbles, or even bags of jacks — it sometimes pours like a liquid, and other times “jams” up, forming a rigid solid.

The physics of jamming has been well-studied for round and spherical particles, says Duke physics professor Bob Behringer, an expert on granular materials who advises Zhao. But much less is understood about jamming in particles with more complex shapes, like hexapods.

“As soon as you move away from spheres, you can create jammed systems at the drop of a hat,” said Behringer. “People think they understand these systems, but there are still a lot of outstanding questions about how they behave: how do they break? Or how do they respond to shear stress?”

These questions aren’t only interesting to physicists, Behringer says. Architects Karola Dierichs and Achim Menges, collaborators on the project, are experimenting with using custom-designed granular materials, from hexapods to hooks, to create structures like walls and bridges.

Similar to a sandcastle or a bird’s nest, structures made this way can be porous, light, recyclable and even adaptable.

“One of their big ideas is, can you actually design a structure that could build itself or be constructed at random, rather than designing something very precise?” said Zhao.

Zhaos says that the first goal of his project was simply to explore the physical limits of towers built from hexapods. To do so, he constructed towers out stars ranging in size from 2 to 10 centimeters and made from two different materials. For each combination, he investigated how high he could build the tower before it collapsed. He then subjected the towers to various stressors, including vibration, tilting, and added weight.

One of the most surprising findings, Zhao said, was that the friction between the particles — whether they were made of smooth acrylic or rougher nylon — had the biggest impact on the stability of the towers. He also noted that when these towers collapse, they don’t just fall over in a heap, they fall apart in a series of mini avalanches.

CT-Scan of jacks

A 3D illustration of a tower of stars reconstructed from CT-scan data. The red dots indicate the points of contact between the stars. Image courtesy of Jonathan Barés.

The team has published this initial study, which they hope will be used as a “handbook of mechanical rules” to improve the design of aggregate structures, in a special edition of the journal Granular Matter.

As a next step in the experiment, Zhao and collaborator Jonathan Barés are using a CT scanner in the Duke SMIF lab to take detailed 3D pictures of the “skeletons” of these structures. With the data, they hope to find a better understanding of how all the individual contacts between stars add up to a stable tower.

“It is amazing to see how these particles can make stable structures capable of supporting big loads,” said Jonathan Barés, who is a former Duke postdoc. “Just changing a small property of the particles — their ability to interlock — creates a dramatic change in the behavior of the system.”

CITATION: “Packings of 3D stars: stability and structure.” Yuchen Zhao, Kevin Liu, Matthew Zheng, Jonathan Barés, Karola Dietrichs, Achim Menges, and Robert P. Behringer. Granular Matter, April 11, 2016. DOI: 10.1007/s10035-016-0606-4

Kara J. Manke, PhD

Post by Kara Manke

Ghost Hunters: Duke Physicists Track the Changeable Neutrino

One kilometer below the surface of Mount Ikeno in Japan lies Super-Kamiokande, the largest neutrino detector of its kind in the world. This 12-story, cylindrical chamber holds 50,000 tons of water and is lined with over 11,000 tubes that spot the bursts of light emitted when high-energy neutrinos collide with matter.

Nearly 20 years ago, experiments at Super-K and elsewhere revealed that neutrinos can oscillate or change “flavor,” a discovery which proved that the ghostly particles have mass and upended their role in the Standard Model of physics. Since then, Duke physicists Kate Scholberg and Chris Walter have used the massive detector to further explore the nature of these neutrino oscillations, seeking to pin down how and when they change their flavors and what this might mean for our understanding of physics.

SuperK

Within the massive Super-Kamiokande neutrino experiment in Japan, researchers travel by boat to check individual photomultiplier tubes that detect bursts of light created when neutrinos interact with water. Credit: Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo.

On Wednesday, Scholberg and Walter, along with Duke neutrino physicist Phillip S. Barbeau, will tell the story of neutrino oscillations in a talk titled, “Hunting Ghosts, How a 50,000-ton underground detector revealed the changeable nature of the neutrino and altered our view of the Universe,” presented as part of the Natural sciences in the 21st century colloquium.

In preparation for the talk, Scholberg spoke with colloquium organizer Rotem Ben-Shachar about the nature of neutrinos, what makes them so hard to catch, and what they have teach us about the origins of matter in our universe.

What is a neutrino?

Neutrinos, sometimes known as “ghost particles,” are among the known “elementary” particles: unlike atoms, they are not made up of anything smaller. Neutrinos are special because they are neutral, meaning they have no electric charge, and they interact extremely weakly with matter. They also have very tiny masses: a neutrino has no more than about 1/500,000 the mass of an electron. Because of their tiny masses, neutrinos travel at speeds close to the speed of light. Neutrinos come in three “flavors”: electron, muon and tau.

Why are neutrinos so hard to catch?

Neutrinos only interact only via the weak force — this is one of the four known forces, the others being gravity, electromagnetism, and the strong force which holds atomic nuclei together.  As you might guess from the name, the weak force is really feeble, and that means that neutrinos hardly ever interact with matter at all.  Mostly they just pass right through things without leaving any trace. Once in a while, they do interact, leaving a charged particle that you can detect. In order to “catch” a neutrino — to detect the interaction — you need either a huge number of neutrinos, or an enormous detector, or preferably both. For example, Super-Kamiokande is gigantic, but we see only about ten high-energy neutrinos per day in the detector.  On the surface of the Earth, cosmic radiation can easily swamp a signal this slight, so neutrino detectors are often built underground where they are shielded from cosmic radiation.

When we can catch a neutrino, what do we learn from it?

dukebanner

Duke scientists suspended inside the Super-K detector.

Particle physicists like us try to understand the basic nature of matter and energy: our goal is to learn what the universe is made of, and how its constituents interact with one another. We’re also interested in cosmology — the history and evolution of the entire universe. It’s essential to understand the fundamental physics in order to understand what happened after the Big Bang, and why the universe looks as it does today. For instance, nobody understands why the universe is made primarily of matter and not antimatter, which has properties very much like matter, but with opposite charge. The study of neutrinos can give insight into many questions like this one.

What specifically we learn with a neutrino detector depends on the source of neutrino, the type of neutrino, and how far the neutrinos travel.  For instance, at Super-K we can detect neutrinos that come from collisions of cosmic rays, high energy particles from outer space, with the upper atmosphere. These neutrinos travel through the Earth: some of them go a short distance, and some of them travel all the way from the other side of the Earth. What we observe is that neutrinos change from one flavor to another as they travel — it turns out that this can only happen if neutrinos have mass.

The 2015 Nobel prize in physics was awarded for discovery of neutrino oscillations by the Super-Kamiokande and Sudbury Neutrino Observatory experiments. Why was this discovery so important?

The discovery that neutrinos oscillate as they travel — they change their flavor — told us that neutrinos have non-zero mass. This is a really fundamental piece of information. It completely changes the role neutrinos play in the Standard Model of particle physics, and in fact we still don’t know exactly how to fit neutrinos with mass into the picture; how to do this depends on whether neutrinos and antineutrinos are really the same particles or not.

Neutrino mass also matters for cosmology. Since neutrinos have mass, we know they make up some of the unknown “dark matter” of the Universe, but we also now know that neutrinos can only make up a small fraction of the dark matter.  Exactly *how* the neutrinos oscillate also matters, as this depends on fundamental parameters of nature.

SK-NueCand

A 3-D display of a candidate electron-neutrino event in the Super-Kamiokande detector. Each of the colored dots represents a detector that was hit by the light created when the electron neutrino interacted with the detector.

How does your research build on the discovery of neutrino oscillations?

The discovery of oscillations in atmospheric and solar neutrinos by Super-K and SNO has now been confirmed by multiple other experiments, and we’ve made tremendous progress over the past 20 years in refining our understanding of neutrino oscillations. An experiment we are involved in at Duke, T2K (“Tokai to Kamioka”), sends a beam of high-energy neutrinos from an accelerator a distance of 300 km to Super-K.  This experiment has discovered new oscillation properties of neutrinos and will continue to take data over the next several years.

But there are still big questions out there about neutrinos — we have three neutrinos, but we don’t know if we have two heavier ones and one light one, or two light ones and a heavy one, which matters for the big picture. We don’t know if oscillations of neutrinos and antineutrinos happen differently. We don’t know if neutrinos and antineutrinos are really the same particles.  The answers to these questions may help us understand the origin of matter.  A next-generation beam experiment, DUNE, will send a beam of neutrinos 1300 kilometers from Fermilab to South Dakota and may answer some of these questions — and if we are lucky, we’ll also catch a burst of neutrinos from a supernova.

The Natural sciences in the 21st century colloquium will be held Wednesday, April 13 at 4:30 PM in Duke’s Gross Hall, room 107.

Kara J. Manke, PhD

Post by Kara Manke

Posted in Faculty, Lecture, Physics | Comments Off on Ghost Hunters: Duke Physicists Track the Changeable Neutrino

Finding other Earths: the Chemistry of Star and Planet Formation

In the last two decades, humanity has discovered thousands of extrasolar planetary systems. Recent studies of star- and planet-formation have shown that chemistry plays a pivotal role in both shaping these systems and delivering water and organic species to the surfaces of nascent terrestrial planets. Professor Geoffrey A. Blake in Chemistry at the California Institute of Technology talked to Duke faculty and students over late-afternoon pizza in the Physics building on the role of chemistry in star and planet formation and finding other Earth-like planets.

milky way

The Milky Way rising above the Pacific Ocean and McKay Cove off the central California coast.

In the late 18th century, French scholar Pierre-Simon Laplace analyzed what our solar system could tell us about the formation & evolution of planetary systems. Since then, scientists have used the combination our knowledge for small bodies like asteroids, large bodies such as planets, and studies of extrasolar planetary systems to figure out how solar systems and planets are formed.

The "Astronomer's periodic table," showing the relative contents of the various elements present in stars.

The “Astronomer’s periodic table,” showing the relative contents of the various elements present in stars like the sun.

In 2015, Professor Blake and other researchers investigated more into ingredients in planets necessary for the development of life. Using the Earth and our solar system as the basis for their data, they explored the relative disposition of carbon and nitrogen in each stage of star and planet formation to learn more about core formation and atmospheric escape. Analyzing the carbon-silicon atomic ratio in planets and comets, Professor Blake discovered that rocky bodies in the solar system are generally carbon-poor. Since carbon is essential for our survival, however, Blake and his colleagues would like to determine the range of carbon content that terrestrial planets can have and still have active biosystem.

Analysis of C/Si ratios in extraterrestrial bodies revealed low carbon content in the formation of Earth-like planets.

Analysis of C/Si ratios in extraterrestrial bodies revealed low carbon content in the formation of Earth-like planets.

With the Kepler mission, scientists have detected a variety of planetary objects in the universe. How many of these star-planet systems – based on measured distributions – have ‘solar system’ like outcomes? A “solar system” like planetary system has at least one Earth-like planet at approximately 1 astronomical unit (AU) from the star – where more ideal conditions for life can develop – and at least one ice giant or gas giant like Jupiter at 3-5 AU in order to keep away comets from the Earth-like planet. In our galaxy alone, there are around 100 billion stars and at least as many planets. For those stars similar to our sun, there exist over 4 million planetary systems similar to our solar system, with the closest Earth-like planet at least 20 light years away. With the rapid improvement of scientific knowledge and technology, Professor Blake estimates that we would be able to collect evidence within next 5-6 years of planets within 40-50 light years to determine if they have a habitable atmosphere.

planet

Graph displaying the locations of Earth-like planets found at 0.01-1 AU from a star, and Jupiter-like planets at 0.01-50 AU from a star.

How does an Earth and a Jupiter form at their ideal distances from a star? Let’s take a closer look at how stars and planets are created – via the astrochemical cycle. Essentially, dense clouds of gas and dust become so opaque and cold that they collapse into a disk. The disk, rotating around a to-be star, begins to transport mass in toward the center and angular momentum outward. Then, approximately 1% of the star mass is left over from the process, which is enough to form planets. This is also why planets around stars are ubiquitous.

 

The Astrochemical Cycle: how solar systems are formed.

The Astrochemical Cycle: how solar systems are formed.

How are the planets formed? The dust grains unused by the star collide and grow, forming larger particles at specific distances from the star – called snowlines – where water vapor turns into ice and solidifies. These “dust bunnies” grow into planetesimals (~10-50 km diameter), such as asteroids and comets. If the force of gravity is large enough, the planetesimals increase further in size to form oligarchs (~0.1-10 times the mass of the Earth), that then become the large planets of the solar system.

Depiction

Depiction of the snow line for planet formation.

In our solar system, a process called dynamic reorganization is thought to have occurred that restructured the order of our planets, putting Uranus before Neptune. This means that if other solar systems did not undergo such dynamic reorganization at an early point in formation of solar system, then other Earths may have lower organic and water content than our Earth. In that case, what constraints do we need to apply to determine if a water/organic delivery mechanism exists for exo-Earths? Although we do not currently have the scientific knowledge to answer this, with ALMA and the next generation of optical/IR telescopes, we will be able image the birth of solar systems directly and better understand how our universe came to be.

To the chemistry students at Duke, Professor Blake relayed an important message: learn chemistry fundamentals very carefully while in college. Over the next 40-50 years, your interests will change gears many times. Strong fundamentals, however, will serve you well, since you are now equipped to learn in many different areas and careers.

Professor Blake and the team of former and current Caltech researchers.

Professor Blake and the team of former and current Caltech researchers.

Learn more about the Blake research group or their work.

Anika_RD_hed100_2

By Anika Radiya-Dixit.

 

The Future of 3D Printing in Medicine

While 3D printers were once huge, expensive devices only available to the industrial elite, they have rapidly gained popularity over the last decade with everyday consumers. I enjoy printing a myriad of objects at the Duke Colab ranging from the Elder Wand to laptop stands.

One of the most important recent applications of 3D printing is in the medical industry. Customized implants and prosthetics, medical models and equipment, and synthetic skin are just a few of the prints that have begun to revolutionize health care.

3D printed prosthetic leg: “customizable, affordable and beautiful.”

Katie Albanese is a student in the Medical Physics Graduate Program who has been 3D printing breasts, abdominal skeletons, and lungs to test the coherent scatter x-ray imaging system she developed. Over spring break, I had the opportunity to talk with Katie about her work and experience. She uses the scatter x-ray imaging system to identify the different kinds of tissue, including tumors, within the breast. When she isn’t busy printing 3D human-sized breasts to determine if the system works within the confines of normal breast geometries, Katie enjoys tennis, running, napping and watching documentaries in her spare time. Below is the transcript of the interview.

How did you get interested in your project?

When I came to Duke in 2014, I had no idea what research lab I wanted to join within the Medical Physics program. After hearing a lot of research talks from faculty within my program, I ultimately chose my lab based on how well I got along with my current advisor, Anuj Kapadia in the Radiology department. He had an x-ray project in the works with the hope of using coherent scatter in tissue imaging, but the system had yet to be used on human-sized objects.

Could you tell me more about the scatter x-ray imaging system you’ve developed?

Normally, scatter in a medical image is actively removed because it doesn’t contribute to diagnostic image quality in conventional x-ray. However, due to the unique inter-atomic spacing of every material – and Bragg’s law – every material has a unique scatter signature. So, using the scattered radiation from a sample (instead of the primary x-ray beam that is transmitted through the sample), we can identify the inter-atomic spacing of that material and trace that back to what the material actually is to a library of known inter-atomic spacings.

Bragg diffraction: Two beams with identical wavelength and phase approach a crystalline solid and are scattered off two different atoms within it.

How do you use this method with the 3D printed body parts?

One of the first things we did with the system was see if it could identify the different types of human tissue (ex. fat, muscle, tumor). The breast has all of these tissues within a relatively small piece of anatomy, so that is where the focus began. We were able to show that the system could discern different tissue types within a small sample, such as a piece of excised human tissue. However, in order to use any system in-vivo, which is ideally the aim, you have to determine whether or not it works on a normal human geometry. Another professor in our department built a dedicated breast CT system, so we used patient scans from that machine to model and print an accurate breast, both in anatomy and physical size.

 

What are the three biggest benefits of the x-ray imaging system for future research? 

Main breast phantom used and a mammogram of that phantom with tissue samples in it

Main breast phantom used and a mammogram of that phantom with tissue samples in it

Coherent scatter imaging is gaining momentum as an imaging field. At the SPIE Medical Imaging Conference a few weeks ago in San Diego, there was a dedicated section on the use of scatter imaging (and our group had 3 out of 5 talks on the topic!). One major benefit is that it is noninvasive. There is always a need for a noninvasive diagnostic step in the medical field. One thing we foresee this technology being used for could be a replacement for certain biopsy procedures. For instance, if a radiologist finds something suspicious in a mammogram, a repeat scan of that area could be taken on a scatter imaging system to determine whether or not the suspicious lesion is malignant or not. It has the potential to reduce the number of unnecessary invasive (and painful!) biopsies done in cancer diagnosis.

Another thing we envision, and work has been done on this in our group, is using this imaging technique for intra-operative margin detection. When a patient gets a lumpectomy or mastectomy, the excised tissue is sent to pathology to make sure all the cancer has been removed from the patient. This is done by assessing whether or not there is cancer on the outer margins of the sample and can often take several days. If there is cancerous tissue in the margin, then it is likely that the extent of the cancer was not removed from the patient and a repeat surgery is required. Our imaging system has the potential to scan the entirety of the tissue sample while the patient is still open in the operating room. With further refinement of system parameters and scanning technique, this could be a reality and help to prevent additional surgeries and the complications that could arise from that.

What was the hardest or most frustrating part of working on the project? 

We use a coded aperture within the x-ray beam, which is basically a mask that allows us to have a depth-resolved image. The aperture is what tells us where the source of the scatter came from so that we can reconstruct. The location of this aperture relative to the other apparatus within our setup is carefully calibrated, down to the sub-millimeter range. If any part of the system is moved, everything must be recalibrated within the code, which is very time-consuming and frustrating. So basically every time we wanted to move something in our setup to make things better or more efficient, it was like we were redesigning the system from scratch.

 What is your workspace like?

Katie and the team at the AAPM (American Association of Physicists in Medicine) conference from this past summer in Anaheim, CA where she presented in a special session on breast imaging. From left to right: Robert Morris (also in the research lab and getting his degree in MedPhys), Katie, Dr. James Dobbins III (former program director and current Associate Vice Provost for DKU) and Dr. Anuj Kapadia, my advisor and current director of graduate studies in the program

Katie presented in a special session on breast imaging at the American Association of Physicists in Medicine conference this past summer in Anaheim, CA. From left to right: Robert Morris, also working in the lab; Katie; Dr. James Dobbins III, former program director and current Associate Vice Provost for Duke-Kunshan University; and Dr. Anuj Kapadia, Katie’s advisor and current director of graduate studies.

We have a working experimental lab within the hospital. It looks like any other physics lab you might come across- messy, full of wires and strange electronics. It is unique from other labs within the Medical Physics department because a lot of research that is done there focuses on image processing or radiation therapy treatment planning and can be done on just a computer. This lab is very hands-on in that we need to engineer the system ourselves. It is not uncommon for us to be using power tools or soldering or welding.

What do you like best about 3D printing? 

3D printing has become such a great community for creativity. One of my favorite websites now, called Thingiverse, is basically a haven for 3D printable files of anything you could ever dream of, with comments on the best printing settings, printers and inks. You can really print anything you want — I’ve printed everything from breasts, lungs and spines to small animal models and even Harry Potter memorabilia to add to my collection. If you can dream it, you can print it in three dimensions, and I think that’s amazing.

 

Anika_RD_hed100_2By Anika Radiya-Dixit

 

Why care about the gender gap in science and tech?

A day on the job for Christine McKinley

A day on the job for Christine McKinley

Scenes like the one above are engineer Christine McKinley’s favorite views of the construction sites where she manages building designs and contracts with other engineers. McKinley, a mechanical engineer, musician, and author, enjoys the complexities, high stakes and surprises of her job. Engineers, she says, “design against [surprises] but live for surprises.”

One of these surprises, McKinley told an audience last Thursday Feb. 25 in the Nelson Music Room at Duke, was a talk she had with the director of a community college district. He told her “women aren’t as good as math and science.” Shocked and disappointed that a man in charge of the education of the young students would believe this, McKinley pointed out that several of her accomplished colleagues were women. McKinley, like many other women, was frustrated that she has to work harder than men to get a promotion.

Is this changing? Are women today more prevalent in engineering fields than they were twenty to thirty years ago?

The chart below depicts the distribution of engineers in 1989: only 15 percent are women.

Distribution of Engineering Graduates in 1989

Of course, 1989 was 27 years ago and a different cultural time, with Nintendo’s Game Boy and Prince William’s seventh birthday. But the chart below shows how little those numbers have changed.

Distribution of Engineering Graduates in 2015

For mechanical engineers, the gap is much larger: only 7 percent are women (yellow faces), while the blue faces represent men, with the some frowning ones unhappy to be working with the women.

Percent of female mechanical engineers

Percent of female mechanical engineers

When the workers are broken down into teams, according to McKinley, the image below is what it actually feels like to be working as a female mechanical engineer.

What it actually feels like to be a female mechanical engineer

What it actually feels like to be a female mechanical engineer

Let’s start with the most troubling issue regarding the lack of diversity in engineering. If women and people of color are told that we are not good at math and science, and we believe it, then we are choosing a form of helplessness. Specifically, if we don’t pick apart the data and challenge those who made up this story, then it sticks, and the “rumor” becomes a narrative – and that’s dangerous, McKinley said. However, everyone needs to know basic chemistry, math, and physics to participate in conversations about topics such as medicine, NASA, one’s cholesterol level, and energy conservation as a knowledgeable adult. People need to be STEM-literate to be able to analyze this data, and men, especially in the 1950s, didn’t want women to research the facts and prove a competition.

Why should we care about women choosing careers in STEM fields?

Reason 1: Gender financial inequity: STEM grads make more than non-STEM grads

If we care about the gender pay gap, and only 19 percent of engineering graduates are women, then that aggravates the situation. This gender inequity can be addressed – partly – by women choosing to study engineering, McKinley said.

Of course, money is not the only thing in life; we want jobs with meaning, she added. However, even civil engineers understand that they are in a helping profession, always excited to build a new bridge, for example, to help people cross a flooded river. At the same time, money gives one the ability to leave a spouse, to take care of a disabled child, to find a better job, to afford healthier food; making real money gives one a way to become independent and make better choices. Working a job, however, does not imply that we must “sacrifice [our] life and fun.” McKinley enjoys what she does and has a lot of fun on the job; studying math and science, she says, is not that complex with the right motivation and support.

Reason 2: Humanity’s Survival

A coronal mass ejection (CME) is an enormous eruption of gas and magnetic field that launches billions of tons of plasma from the sun’s surface into space. Such an event occurred in 1859. As a result, farmers plowing field with horses noticed a bright flash of light, steam engines continued to run on schedule, and telegraph operators were confused when their telegraph batteries stopped working. Overall, there were few problems due to the limited technology at the time.

Imagine a CME happening today. All our large pieces of equipment – power stations, transformers, and transmission lines – would get fried.

Equipment involved in the transportation of energy from power plants to users

If these power houses blow up, what are we going to do? With three-year lead-time and $2 trillion cost, they will not be repaired in time for us to continue our daily functions. We now have a civilization-changing event on our hands – what Hurricane Katrina gave us, but now, for entire countries. We are in a time where our dependence on technology is constantly rising – until it’s not. In such a disastrous scenario, we will need more engineers. At this time, everyone – men and women – will come together to work on simple, elegant solutions to make the world better.

Currently, we have a mass shortage of engineers, so those today are overbooked with work. If these engineers are unable to find time to think through the entire solution and review all possible sources of error, then it creates a problem not only for engineering but also for the entire world in general. We are in need of good engineers and a diverse workforce to bring together all our ideas for a better world.

McKinley notes that she finds herself more comfortable when there are other women in the room. As a result, the whole team gets more relaxed, “elevating everyone’s game,” and people get more creative and feel more secure in sharing their ideas.

Grace Hopper created the computers advertised in this flyer.

Grace Hopper created the computers advertised in this flyer.

 

Reason 3: The third reason we care about this view about engineering is the history of STEM achievements by women being ignored or the credit being taken by men.

Women who became mathematicians in the 1900s had to fight hard to have their contributions to the field recognized. The world misses out significantly if the achievements of half of humanity are ignored.

Hertha Aryton was a brilliant mathematician who had been elected the first female member of the Institution of Electrical Engineers in 1899. In 1902, she became the first woman nominated a Fellow of the Royal Society of London. “Because she was married, however,” McKinley quoted, “legal counsel advised that the charter of the Royal Society did not allow the Society to elect her to this distinction.”

Amalie Noether was another incredible mathematician who invented a theorem that united symmetry in nature and the universal laws of conservation. Some consider Noether’s theorem, as it is now called, to be as important as Albert Einstein’s theory of relativity. Einstein himself regarded her as most “significant” and “creative” female mathematician of all time. However, McKinley tells the audience, she was denied a working position at universities simply because they did not hire female professors.

In the 1900’s, more than 1000 women joined an organization called Women Airforce Service Pilots. They transported newly-made planes to the fighter pilots; however, many of the planes were untested, causing 38 of them to die in service. While they went through intense military training and had prior experience, the women were considered “civilian volunteers” and had to fight to be recognized. Further, most of the accepted women to the organization were white, and the only African American applicant was asked to withdraw her application.

Nancy Fitzroy was American engineer and heat transfer expert in the 1900s. She received plenty of criticism as well, but she said it didn’t affect her: “The reaction I pretty much have gotten most of my life is ‘little girl, what are you doing here?’ but I was a good engineer. That’s what made all the difference.”

 

Curiosity, inventiveness, and the urge to improve are not male traits. They are human traits. Women are half of humanity; they are not the spectators. Women must step up and contribute even if it is more difficult. Constantly underestimated as a female mechanical engineer, McKinley says she uses this underestimation as fuel to work harder and become better.

Being an engineer is worth it. Ask great questions, and be really good.

Remember, McKinley told her audience, that engineering is full of surprises. And for people who underestimate you, you’ll be that surprise.

 

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C

Christine McKinley gave her talk in the Nelson Music Building at Duke last Thursday for Feminist/Women’s month.

Christine McKinley is a mechanical engineer, musician, and author. Her musical Gracie and the Atom, won a Portland Drammy for Original Score. Her book Physics for Rock Stars was published in 2014 by Penguin Random House. Christine hosted Brad Meltzer’s Decoded on History Channel and Under New York on Discovery Channel.

You can view her website, read her book, or contact her via email.

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Anika_RD_hed100_2 By Anika Radiya-Dixit

 

 

3-D Movies of Life at Nanoscale Named Best Science Paper of the Year

If you’ve ever wanted to watch a killer T cell in action, or see human cancer make new cells up-close, now is your chance.

A collection of 3-D movies captured by Duke biology professor Dan Kiehart and colleagues has won the 2015 Newcomb Cleveland Prize for most outstanding paper in the journal Science.

The paper uses a new imaging technique called lattice light-sheet microscopy to make super high-resolution three-dimensional movies of living things ranging from single cells to developing worm and fly embryos.

Cutting-edge microscopes available on many campuses today allow researchers to take one or two images a second. But the lattice light-sheet microscope, co-developed by 2014 Nobel Prize winner Eric Betzig, lets researchers take more than 50 images a second, and in the specimen’s natural state, without smooshing it under a cover slip.

You can watch slender antennae called filopodia extend from the surface of a human cancer cell, or tiny rods called microtubules, several thousand times finer than a human hair, growing and shrinking inside a slide mold.

Daniel Kiehart and former Duke postdoctoral fellow Serdar Tulu made a video of the back side of a fruit fly embryo during a crucial step in its development into a larva.

Chosen from among nominations submitted by readers of Science, the paper has been viewed more than 20,000 times since it was first published on October 24, 2014.

The award was announced on February 12, 2016, at an award ceremony held during the annual meeting of the American Association for the Advancement of Science (AAAS) in Washington, D.C.

Winners received a commemorative plaque and $25,000, to be shared among the paper’s lead authors Eric Betzig, Bi-Chang Chen, Wesley Legant and Kai Wang of Janelia Farm Research Campus.

Read more: “Lattice light-sheet microscopy: Imaging molecules to embryos at high spatiotemporal resolution,” Chen, B.-C., et al. Science, October 2014. DOI:10.1126/science.1257998

 

Post by Robin A. Smith Robin Smith