SwRI develops off-road autonomous driving tools focused on camera vision

SwRI is exploring using stereo cameras, or stereovision, as an alternative to lidar sensors in automated vehicles. SwRI's stereovision algorithms create disparity maps that estimate the depth of roadway features and obstacles. The left image shows how a conventional camera sees an off-road trail. The middle image shows a lidar image of the same trail. The right image shows a stereovision disparity map based on SwRI's algorithms, where colors indicate the distance of detected objects (yellow is near and blue is far). The gray/white in the lidar image suggests the outline of trees and a vehicle hood, but it does not indicate depth or distance.
Image Credit: Courtesy of Southwest Research Institute

Southwest Research Institute has developed off-road autonomous driving tools with a focus on stealth for the military and agility for space and agriculture clients. The vision-based system pairs stereo cameras with novel algorithms, eliminating the need for lidar and active sensors.

“We reflected on the toughest machine vision challenges and then focused on achieving dense, robust modeling for off-road navigation,” said Abe Garza, a research engineer in SwRI’s Intelligent Systems Division.

Through internal research, SwRI engineers developed a suite of tools known as the Vision for Off-Road Autonomy (VORA). The passive system can perceive objects, model environments and simultaneously localize and map while navigating off-road environments.

The VORA team envisioned a camera system as a passive sensing alternative to lidar, a light detection and ranging sensor, that emits active lasers to probe objects and calculate depth and distance. Though highly reliable, lidar sensors produce light that can be detected by hostile forces. Radar, which emits radio waves, is also detectable. GPS navigation can be jammed, and its signals are often blocked in canyons and mountains, which can limit agricultural automation.

Nanosurgical tool could be key to cancer breakthrough

Electron microscopy image of the nanopipette.
Photo Credit: Dr Alexander Kulak

A nanosurgical tool - about 500 times thinner than a human hair - could give insights into cancer treatment resistance that no other technology has been able to do, according to a new study.

The high-tech double-barrel nanopipette, developed by University of Leeds scientists, and applied to the global medical challenge of cancer, has - for the first time - enabled researchers to see how individual living cancer cells react to treatment and change over time – providing vital understanding that could help doctors develop more effective cancer medication.  

The tool has two nanoscopic needles, meaning it can simultaneously inject and extract a sample from the same cell, expanding its potential uses. And the platform’s high level of semi-automation has sped up the process dramatically, enabling scientists to extract data from many more individual cells, with far greater accuracy and efficiency than previously possible, the study shows. 

Currently, techniques for studying single cells usually destroy them, meaning a cell can be studied either before treatment, or after.  

This device can take a “biopsy” of a living cell repeatedly during exposure to cancer treatment, sampling tiny extracts of its contents without killing it, enabling scientists to observe its reaction over time. 

During the study, the multi-disciplinary team, featuring biologists and engineers, tested cancer cells’ resistance to chemotherapy and radiotherapy using glioblastoma (GBM) - the deadliest form of brain tumor - as a test case, because of its ability to adapt to treatment and survive. 

Completely recycled viscose for the first time

Edvin Bågenholm-Ruuth
Photo Credit: Courtesy of Lund University

At present, viscose textiles are made of biomass from the forest, and there is no such thing as fully recycled viscose. Researchers at Lund University in Sweden have now succeeded in making new viscose – from worn-out cotton sheets.

Old textiles around the world end up at the rubbish tip and are often burned. In Sweden, they are generally burned to produce district heating. Extensive development work is being conducted to give old clothes and textiles a worthier ending. 

The planet really needs recycled textiles, as it takes a lot of energy, water and land to cultivate cotton and other plant sources for textiles. 

However, there are many challenges.

“Cellulose chains, the main component in plant fibers, are complex and long. Cotton textiles are also intensively treated with dyes, protective agents and other chemicals. And then there is all the ingrained grime in the form of skin flakes and fats,” says Edvin Bågenholm-Ruuth, doctoral student in chemical engineering at Lund University. 

Possible ‘Trojan Horse’ found for treating stubborn bacterial infections

Transmission electron microscope (TEM) image of the bacterial cell with an extracellular vesicle attached.
Image Credit: Courtesy of Washington State University

Bacteria can be tricked into sending death signals to stop the growth of their slimy, protective homes that lead to deadly infections, a new study demonstrates.

The discovery by Washington State University researchers could someday be harnessed as an alternative to antibiotics for treating difficult infections. Reporting in the journal Biofilm, the researchers used the messengers, which they named death extracellular vesicles (D-EVs), to reduce growth of the bacterial communities by up to 99.99% in laboratory experiments.

“Adding the death extracellular vesicles to the bacterial environment, we are kind of cheating the bacteria cells,” said Mawra Gamal Saad, first author on the paper and a graduate student in WSU’s Gene and Linda Voiland School of Chemical Engineering and Bioengineering. “The cells don’t know which type of EVs they are, but they take them up because they are used to taking them from their environment, and with that, the physiological signals inside the cells change from growth to death.”

Scientists Have Created Organic Films to Charge Cardiac Pacemakers

The resulting films have high biocompatibility.
Photo Credit: Andrei Ushakov

UrFU scientists, together with colleagues from the University of Aveiro (Portugal), have succeeded in obtaining biocompatible crystalline films. They have high piezoelectric properties - they generate an electric current under mechanical or thermal stress. This property will be useful in the design of elements for invasive medical devices, such as pacemakers. Detailed information about the films obtained and the new method of their synthesis has been published by the scientists in ACS Biomaterials Science & Engineering. 

"We have succeeded in obtaining films from diphenylalanine that have high piezoelectric properties comparable to their inorganic counterparts. Under mechanical or thermal stress, these films generate electricity. The use of such films will be particularly useful for making invasive cardiac pacemakers - devices that reside inside the human body. When the heart moves or beats, these films generate electricity, which is stored in the pacemaker's batteries. Energy storage devices based on such materials could solve the problem of replacing depleted batteries and reduce the number of surgical procedures," explains Denis Alikin, Head of the Laboratory of Functional Nanomaterials and Nanodevices at the UrFU Research Institute of Physics and Applied Mathematics.

New dressing robot can ‘mimic’ the actions of care-workers

The world's first bimanual dressing robot system mimics how caregivers assist humans in dressing.
Photo Credit: Courtesy of University of York

Scientists have developed a new robot that can ‘mimic’ the two-handed movements of care-workers as they dress an individual.

Until now, assistive dressing robots, designed to help an elderly person or a person with a disability get dressed, have been created in the laboratory as a one-armed machine, but research has shown that this can be uncomfortable for the person in care or impractical. 

To tackle this problem, Dr Jihong Zhu, a robotics researcher at the University of York’s Institute for Safe Autonomy, proposed a two-armed assistive dressing scheme, which has not been attempted in previous research, but inspired by caregivers who have demonstrated that specific actions are required to reduce discomfort and distress to the individual in their care.

It is thought that this technology could be significant in the social care system to allow care-workers to spend less time on practical tasks and more time on the health and mental well-being of individuals. 

Study unlocks nanoscale secrets for designing next-generation solar cells

A team of MIT researchers and several other institutions has revealed ways to optimize efficiency and better control degradation, by engineering the nanoscale structure of perovskite devices. Team members include Madeleine Laitz, left, and lead author Dane deQuilettes.
Photo Credit: Courtesy of the researchers
(CC BY-NC-ND 4.0 DEED)

Perovskites, a broad class of compounds with a particular kind of crystal structure, have long been seen as a promising alternative or supplement to today’s silicon or cadmium telluride solar panels. They could be far more lightweight and inexpensive, and could be coated onto virtually any substrate, including paper or flexible plastic that could be rolled up for easy transport.

In their efficiency at converting sunlight to electricity, perovskites are becoming comparable to silicon, whose manufacture still requires long, complex, and energy-intensive processes. One big remaining drawback is longevity: They tend to break down in a matter of months to years, while silicon solar panels can last more than two decades. And their efficiency over large module areas still lags behind silicon. Now, a team of researchers at MIT and several other institutions has revealed ways to optimize efficiency and better control degradation, by engineering the nanoscale structure of perovskite devices.

The study reveals new insights on how to make high-efficiency perovskite solar cells, and also provides new directions for engineers working to bring these solar cells to the commercial marketplace. The work is described today in the journal Nature Energy, in a paper by Dane deQuilettes, a recent MIT postdoc who is now co-founder and chief science officer of the MIT spinout Optigon, along with MIT professors Vladimir Bulovic and Moungi Bawendi, and 10 others at MIT and in Washington state, the U.K., and Korea.

“Ten years ago, if you had asked us what would be the ultimate solution to the rapid development of solar technologies, the answer would have been something that works as well as silicon but whose manufacturing is much simpler,” Bulovic says. “And before we knew it, the field of perovskite photovoltaics appeared. They were as efficient as silicon, and they were as easy to paint on as it is to paint on a piece of paper. The result was tremendous excitement in the field.”

You may be breathing in more tiny nanoparticles from your gas stove than from car exhaust

Brandon Boor, a Purdue associate professor of civil engineering, studies how everyday activities like cooking on a gas stove can affect indoor air quality.
Photo Credit: Kelsey Lefever / Purdue University

Cooking on your gas stove can emit more nano-sized particles into the air than vehicles that run on gas or diesel, possibly increasing your risk of developing asthma or other respiratory illnesses, a new Purdue University study has found.

“Combustion remains a source of air pollution across the world, both indoors and outdoors. We found that cooking on your gas stove produces large amounts of small nanoparticles that get into your respiratory system and deposit efficiently,” said Brandon Boor, an associate professor in Purdue’s Lyles School of Civil Engineering, who led this research.

Based on these findings, the researchers would encourage turning on a kitchen exhaust fan while cooking on a gas stove. 

The study, published in the journal PNAS Nexus, focused on tiny airborne nanoparticles that are only 1-3 nanometers in diameter, which is just the right size for reaching certain parts of the respiratory system and spreading to other organs. 

Recent studies have found that children who live in homes with gas stoves are more likely to develop asthma. But not much is known about how particles smaller than 3 nanometers, called nanocluster aerosol, grow and spread indoors because they’re very difficult to measure.

“These super tiny nanoparticles are so small that you’re not able to see them. They’re not like dust particles that you would see floating in the air,” Boor said. “After observing such high concentrations of nanocluster aerosol during gas cooking, we can’t ignore these nano-sized particles anymore.”

Human stem cells coaxed to mimic the very early central nervous system

Jianping Fu, Ph.D., Professor of Mechanical Engineering at the University of Michigan and the corresponding author of the paper being published at Nature discusses his team’s work in their lab with Jeyoon Bok, Ph.D. candidate at the Department of Mechanical Engineering.
Photo Credit: Marcin Szczepanski, Michigan Engineering

The first stem cell culture method that produces a full model of the early stages of the human central nervous system has been developed by a team of engineers and biologists at the University of Michigan, the Weizmann Institute of Science, and the University of Pennsylvania.

“Models like this will open doors for fundamental research to understand early development of the human central nervous system and how it could go wrong in different disorders,” said Jianping Fu, U-M professor of mechanical engineering and corresponding author of the study in Nature.

The system is an example of a 3D human organoid—stem cell cultures that reflect key structural and functional properties of human organ systems but are partial or otherwise imperfect copies.

“We try to understand not only the basic biology of human brain development, but also diseases—why we have brain-related diseases, their pathology, and how we can come up with effective strategies to treat them,” said Guo-Li Ming, who along with Hongjun Song, both Perelman Professors of Neuroscience at UPenn and co-authors of the study, developed protocols for growing and guiding the cells and characterized the structural and cellular characteristics of the model.

Snake robot could save lives

A search and rescue operation after an earthquake is a complicated task. One thing is to retrieve the potential survivors safely from the rubble. Even more difficult is finding out where they are.

It is precisely this kind of work that, among other things, a snake robot equipped with sensors and cameras could help solve. Such one is currently being developed by researchers at the Faculty of Engineering at the University of Southern Denmark.

They have recently published an article about the project in the journal Device.

We have made a robot capable of rectilinear locomotion - that is, movement in a straight line - as observed in snakes, says PhD student Burcu Seyidoğlu.

Future applications include search and rescue operations, field inspection, and space exploration. Especially in scenarios requiring navigation through confined spaces where body flexion is not feasible.

A Novel Method for Easy and Quick Fabrication of Biomimetic Robots with Life-Like Movement

Ultraviolet-laser processing is a promising technique for developing intricate microstructures, enabling complex alignment of muscle cells, required for building life-like biohybrid actuators, as shown by Tokyo Tech researchers. Compared to traditional complex methods, this innovative technique enables easy and quick fabrication of microstructures with intricate patterns for achieving different muscle cell arrangements, paving the way for biohybrid actuators capable of complex, flexible movements.

Biomimetic robots, which mimic the movements and biological functions of living organisms, are a fascinating area of research that can not only lead to more efficient robots but also serve as a platform for understanding muscle biology. Among these, biohybrid actuators, made up of soft materials and muscular cells that can replicate the forces of actual muscles, have the potential to achieve life-like movements and functions, including self-healing, high efficiency, and high power-to-weight ratio, which have been difficult for traditional bulky robots that require heavy energy sources. One way to achieve these life-like movements is to arrange muscle cells in biohybrid actuators in an anisotropic manner. This involves aligning them in a specific pattern where they are oriented in different directions, like what is found in living organisms. While previous studies have reported biohybrid actuators with significant movement using this technique, they have mostly focused on anisotropically aligning muscle cells in a straight line, resulting in only simple motions, as opposed to the complex movement of native muscle tissues such as twisting, bending, and shrinking. Real muscle tissues have a complex arrangement of muscle cells, including curved and helical patterns.

Invasive weed could be turned into a viable economic crop

Prof Rahman and Dr Karim collecting paddy melons for urease enzyme extraction.
Photo Credit: Courtesy of University of South Australia

One of the most invasive Australian weeds is being touted as a potential economic crop, with benefits for the construction, mining and forestry industries, and potentially many First Nations communities.

The prickly paddy melon weed, which costs the agricultural industry around $100 million a year in lost grain yields, cattle deaths, and control measures, could turn into an unlikely money spinner as a source of urease enzymes to create bio cement and prevent soil erosion.

In a world-first study, researchers at the University of South Australia (UniSA) screened 50 native plants and weeds to find a cheaper and more environmentally friendly source for bulk producing of urease enzymes to strengthen soil.

Among the weeds tested, paddy melon ticked all the boxes and was almost as effective as soybean enzymes, which are more expensive and used primarily for food.

UniSA geotechnical engineer Professor Mizanur Rahman and his students collected the paddy melon weed from roadsides in Port Pirie in South Australia. After crushing the seeds and extracting enzymes in a liquid form, they freeze-dried them to create a powdered, high-concentration cementation agent.

Researcher receives Naval Research Laboratory grant to develop more sophisticated sensor array

From left to right, engineering faculty researchers Dongfang Liu, Xudong Zheng, and Qian Xue display the seal whisker specimen they are modeling their advanced sensor array on for improving underwater detection and recognition.
Photo Credit: Travis Lacoss/RIT

Researchers at Rochester Institute of Technology are creating a novel sensor system based on the superior design and detection range found on harbor seal whiskers.

Xudong Zheng, an associate professor in RIT’s Kate Gleason College of Engineering, received a three-year, $746,000 award from the Naval Research Laboratory to build an autonomous underwater detection and tracking system with biological-level sensitivity, accuracy, and intelligence.

With demands for new sensor capabilities, increased sensitivity and accuracy could significantly advance underwater scientific explorations, such as tracking anomalies and seismic events in areas currently inaccessible or in improvements to robotic functions and military stealth missions.

“This is the next stage of development of stronger sensors,” said Zheng, whose team published findings in Frontiers in Robotics and AI. “Some early results of our computer simulations show that the sensor array combined with ‘smart’ algorithms could provide more smart perceptions and better reasoning regarding the signal pattern and how it corresponds to flow patterns.”

Innovative materials to combat bacteria

Three bacteria from the ESKAPE group: Staphylococcus aureus (yellow), Pseudomonas aeruginosa (short thick blue rods) and Escherichia coli (long blue rods).
Image Credit: © UNIGE

While crucial to biotechnology, bacteria can also cause severe disease, exacerbated by their increasing resistance to antibiotics. This duality between economic benefits and infectious risks underlines the importance of finding ways to control their development. A team at the University of Geneva (UNIGE) is currently developing a new generation of bactericidal alloys, with a wide range of industrial applications. They could be used to treat the contact surfaces responsible for their transmission. The project, which is supported by Innosuisse, will take 18 months to complete.

Resistance to antimicrobial drugs - such as antibiotics and antivirals - is a global public health issue. According to the World Health Organization (WHO), it is currently responsible for 700,000 deaths a year worldwide. If no action is taken, the number of deaths will rise to 10 million a year by 2050, with dramatic consequences for public health and the economy.

To promote and guide research in this field, the WHO has published a list of pathogens that should be targeted as a matter of priority, because they are particularly threatening to human health. The list includes Staphylococcus aureus and E. coli bacteria, which are associated with the most common hospital-acquired infections, as well as salmonella. Contaminated contact surfaces (utensils, handles, stair railings) play a fundamental role in their transmission.

New Algorithm Disentangles Intrinsic Brain Patterns from Sensory Inputs

Image Credit: Omid Sani, Using Generative Ai

Maryam Shanechi, Dean’s Professor of Electrical and Computer Engineering and founding director of the USC Center for Neurotechnology, and her team have developed a new machine learning method that reveals surprisingly consistent intrinsic brain patterns across different subjects by disentangling these patterns from the effect of visual inputs.

The work has been published in the Proceedings of the National Academy of Sciences (PNAS).

When performing various everyday movement behaviors, such as reaching for a book, our brain has to take in information, often in the form of visual input — for example, seeing where the book is. Our brain then has to process this information internally to coordinate the activity of our muscles and perform the movement. But how do millions of neurons in our brain perform such a task? Answering this question requires studying the neurons’ collective activity patterns, but doing so while disentangling the effect of input from the neurons’ intrinsic (aka internal) processes, whether movement-relevant or not.

That’s what Shanechi, her PhD student Parsa Vahidi, and a research associate in her lab, Omid Sani, did by developing a new machine-learning method that models neural activity while considering both movement behavior and sensory input.

Blue PHOLEDs: Final color of efficient OLEDs finally viable in lighting

Jaesang Lee, Electrical Engineering PhD Student, demonstrates use of an earlier blue PHOLED innovation by University of Michigan professor Steve Forrest’s research group in 2014. Forrest’s lab introduced PHOLEDs to the world in the early 2000s and has been trying to improve the lifetime of blue PHOLEDs ever since. Now, they might finally be hardy enough to use in lighting applications. Image credit: Joseph Xu, Michigan Engineering Communications & Marketing The blue LEDs were developed in EECS Professor Stephen Forrest’s lab groups and are for use in cell phones, tablets, and other electronics. The LEDs’ lifetime has been enhanced by a factor of ten, allowing for more efficient use.
Photo Credit: Joseph Xu, Michigan Engineering Communications & Marketing

Lights could soon use the full color suite of perfectly efficient organic light-emitting diodes, or OLEDs, that last tens of thousands of hours, thanks to an innovation from physicists and engineers at the University of Michigan.

The U-M team’s new phosphorescent OLEDs, commonly referred to as PHOLEDs, can maintain 90% of the blue light intensity for 10-14 times longer than other designs that emit similar deep blue colors. That kind of lifespan could finally make blue PHOLEDs hardy enough to be commercially viable in lights that meet the Department of Energy’s 50,000-hour lifetime target. Without a stable blue PHOLED, OLED lights need to use less-efficient technology to create white light.

The lifetime of the new blue PHOLEDs currently is only long enough to use as lighting, but the same design principle could be combined with other light-emitting materials to create blue PHOLEDs hardy enough for TVs, phone screens and computer monitors. Display screens with blue PHOLEDs could potentially increase a device’s battery life by 30%.

Shock wave photographed passing through a single cell

Images of an underwater shock wave moving through a HeLa cell.
Using this new technology, the researchers could see the difference between how the shock wave moved inside and outside of a cell submerged in water. They noted that the results suggested that the cell structure shifts with the visualized wavefront position (shown in the red/ orange line in the image).
 Image Credit: © 2023 Saiki et al. University of Tokyo

A microscopic shock wave has been photographed passing through a single biological cell, thanks to a new photography technique. Nanosecond photography uses ultrafast electronic cameras to take images at the speed of a billionth of a second. However, image quality and exposure time are typically limited. Now, a team led by researchers at the University of Tokyo has achieved superfine images taken over multiple timescales at high-speed using a system they named spectrum circuit. Spectrum circuit bridges the gap between optical imaging and conventional electronic cameras, enabling photography at ultrafast speeds with less blur and more accuracy. This technology has potential applications for science, medicine and industry.

You’re waiting with your camera for just the right moment. Suddenly, your subject speeds by and you’ve barely clicked the shutter. Missed it. Timing can be everything in photography and capturing images at high speed poses a particular challenge. But thanks to advances in camera technology, these days we can see the world like never before. Whether it’s the sweat on a racing cyclist’s brow, the focus in the eyes of a swooping falcon or, with this latest improvement in nanosecond photography, the movement of a shock wave passing through a microscopic single cell at high speed.

Novel Catalyst System for CO2 Conversion

Kevinjeorjios Pellumbi with the experimental setup for CO2 conversion
Photo Credit: © RUB, Marquard

Researchers are constantly pushing the limits of technology by breaking new ground in CO2 conversion. Their goal is to turn the harmful greenhouse gas into a valuable resource.

Research groups around the world are developing technologies to convert carbon dioxide (CO2) into raw materials for industrial applications. Most experiments under industrially relevant conditions have been carried out with heterogeneous electrocatalysts, i.e. catalysts that are in a different chemical phase to the reacting substances. However, homogeneous catalysts, which are in the same phase as the reactants, are generally considered to be more efficient and selective. To date, there haven’t been any set-ups where homogeneous catalysts could be tested under industrial conditions. A team headed by Kevinjeorjios Pellumbi and Professor Ulf-Peter Apfel from Ruhr University Bochum and the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT in Oberhausen has now closed this gap. The researchers outlined their findings in the journal Cell Reports Physical Science.

“Our work aims to push the boundaries of technology in order to establish an efficient solution for CO2 conversion that will transform the climate-damaging gas into a useful resource,” says Ulf-Peter Apfel. His group collaborated with the team led by Professor Wolfgang Schöfberger from the Johannes Kepler University Linz and researchers from the Fritz Haber Institute in Berlin.

New brain-like transistor mimics human intelligence

An artistic interpretation of brain-like computing.
Illustration Credit: Xiaodong Yan/Northwestern University

Taking inspiration from the human brain, researchers have developed a new synaptic transistor capable of higher-level thinking.

Designed by researchers at Northwestern University, Boston College and the Massachusetts Institute of Technology (MIT), the device simultaneously processes and stores information just like the human brain. In new experiments, the researchers demonstrated that the transistor goes beyond simple machine-learning tasks to categorize data and is capable of performing associative learning.

Although previous studies have leveraged similar strategies to develop brain-like computing devices, those transistors cannot function outside cryogenic temperatures. The new device, by contrast, is stable at room temperatures. It also operates at fast speeds, consumes very little energy and retains stored information even when power is removed, making it ideal for real-world applications.

“The brain has a fundamentally different architecture than a digital computer,” said Northwestern’s Mark C. Hersam, who co-led the research. “In a digital computer, data moves back and forth between a microprocessor and memory, which consumes a lot of energy and creates a bottleneck when attempting to perform multiple tasks at the same time. On the other hand, in the brain, memory and information processing are co-located and fully integrated, resulting in orders of magnitude higher energy efficiency. Our synaptic transistor similarly achieves concurrent memory and information processing functionality to more faithfully mimic the brain.”

RIT researchers develop new technique to study how cancer cells move

Vinay Abhyankar, right, assistant professor of biomedical engineering, works closely with two doctoral students, Mehran Mansouri, left, and Indranil Joshi, on research to assess cancer cell migration processes.
Photo Credit: A. Sue Weisler/RIT

In tumors, cells follow microscopic fibers, comparable to following roads through a city. Researchers at the Rochester Institute of Technology developed a new technique to study different features of these “fiber highways” to provide new insights into how cells move efficiently through the tumor environment.

The study, published in the journal Advanced Functional Materials, focused on contact guidance, a process where migrating cells follow aligned collagen fibers. Understanding this process is crucial, as it plays a key role in cancer metastasis, the spread of cancer to other parts of the body.

“Previous research on contact guidance, a process where cancer cells migrate along aligned collagen fibers, has been largely studied in collagen gels with uniform fiber alignment,” said Vinay Abhyankar, associate professor of biomedical engineering in RIT’s Kate Gleason College of Engineering, and study co-author. “However, the tumor microenvironment also features subtle variations or gradients in fiber alignment, and their role in cell migration has been largely unexplored. We suspected that alignment gradients could efficiently direct cell movement but lacked the technology to test the hypothesis.”