Current noise cancelling technology comes in the form of headphones and earbuds. To cancel noise, these headphones emit an anti-noise signal to contrast the external sounds. The time available for the headphones to produce this anti-noise signal is extremely short. This results in some noise getting through, which is why all these devices must cover the entire ear with noise-canceling material. However, wearing such ear-blocking devices for long periods of time is not comfortable, and can even be harmful.

“Our goal is to not block the ear canal,” said Sheng Shen, lead author and a Ph.D. candidate in the Coordinated Science Laboratory and Dept. of Electrical and Computer Engineering (ECE). “We envision a behind-the-ear device that still achieves noise cancellation as good as the best headphones or earbuds available today.”

The main idea behind this research involves combining wireless IoT networks with noise cancellation. A microphone is placed in the environment that senses sounds and sends them over wireless signals to an earpiece. Since wireless signals travel a million times faster than sound, the earphone can receive the sound information much faster than the actual sound itself.

“This is similar to lightning and thunder — the lightning arrives much before the thunder, allowing people to prepare for the loud rumble,” said Shen’s advisor, Romit Roy Choudhury, an ECE Professor. “Similarly, our ear device gets the sound information in advance, and has much more time to produce a better anti-noise signal.”

Here’s an example of how this technology would work: The person who wants to cancel noise (Alice) would place the IoT microphone away from her, say on her office door. The noise from her coworkers’ conversation in the hallway is picked up by this IoT device and transmitted to Alice’s earpiece over a wireless connection. The actual sound arrives at the earpiece later, and because of this lead time, the noise can be fully canceled. As a result, it is no longer necessary to block the ear canal.

There are however, a few limitations. The IoT microphone needs to be between the noise source and Alice. If noise is coming at her from all directions, a couple more IoT devices would need to be placed around her. In tests conducted during the research, the device designed by Shen and Choudhury’s group outperformed a leading headphone in overall noise cancellation and was rated better by the human participants.

When asked about the potential privacy concerns involved with the device, Shen nullified some of the most common fears.

“The most common privacy concern is that the device will secretly record someone’s voice,” Shen said. “This device is analog, so it has no capacity to record the sound. The moment the device hears the sound it is sent out wirelessly.”

This differentiation is what separates Shen’s device from many IoT devices commonly used today, such as Amazon Echo and Google Home, which must record voice samples in order to operate.

Shen and his colleagues are already receiving attention for their work. The research paper about the project was recently selected for presentation at the upcoming Association for Computing Machinery Special Interest Group on Data Communication (ACM SIGCOMM) Conference which takes place in Budapest, Hungary, in late August. The conference brings together global researchers across the field of computer networking and communications.

“This is bound to change the way we think of noise cancellation, where networks of IoT sensors coordinate to enable quieter and more comfortable environments,” said ECE Assistant Professor Haitham Hassanieh, who is a co-author on this paper. Other co-authors include Nirupam Roy and Junfeng Guan, both ECE Ph.D. students at the University of Illinois Urbana-Champaign.

Looking forward, the team would like to expand the use of their device to provide noise cancellation for more than one individual at a time and make the wearable device even lighter for continuous use.

Rice materials scientist Rouzbeh Shahsavari and his team used molecular models to demonstrate their theory that weak van der Waals forces between the inner surface of the nanotube and the water molecules are strong enough to snap the oxygen and hydrogen atoms into place.

Shahsavari referred to the contents as two-dimensional “ice,” because the molecules freeze regardless of the temperature. He said the research provides valuable insight on ways to leverage atomic interactions between nanotubes and water molecules to fabricate nanochannels and energy-storing nanocapacitors.

A paper on the research appears in the American Chemical Society journal Langmuir.

Shahsavari and his colleagues built molecular models of carbon and boron nitride nanotubes with adjustable widths. They discovered boron nitride is best at constraining the shape of water when the nanotubes are 10.5 angstroms wide. (One angstrom is one hundred-millionth of a centimeter.)

The researchers already knew that hydrogen atoms in tightly confined water take on interesting structural properties. Recent experiments by other labs showed strong evidence for the formation of nanotube ice and prompted the researchers to build density functional theory models to analyze the forces responsible.

Shahsavari’s team modeled water molecules, which are about 3 angstroms wide, inside carbon and boron nitride nanotubes of various chiralities (the angles of their atomic lattices) and between 8 and 12 angstroms in diameter. They discovered that nanotubes in the middle diameters had the most impact on the balance between molecular interactions and van der Waals pressure that prompted the transition from a square water tube to ice.

“If the nanotube is too small and you can only fit one water molecule, you can’t judge much,” Shahsavari said. “If it’s too large, the water keeps its amorphous shape. But at about 8 angstroms, the nanotubes’ van der Waals force starts to push water molecules into organized square shapes.”

He said the strongest interactions were found in boron nitride nanotubes due to the particular polarization of their atoms.

Shahsavari said nanotube ice could find use in molecular machines or as nanoscale capillaries, or foster ways to deliver a few molecules of water or sequestered drugs to targeted cells, like a nanoscale syringe.

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“Conventional filters, like those used to make coffee, allow small objects to pass through while keeping larger objects contained,” said Birgitt Boschitsch, graduate student in mechanical engineering.

She and the research team, however, developed the exact opposite, a stabilized liquid material that screens out smaller objects while allowing larger ones to pass through. The research was published today (Aug. 24) online in Science Advances.

The team experimented with liquids for their unique properties.

“If you put your finger in a glass of water and take it out, the water’s surface self-heals,” explained Tak-Sing Wong, the Wormley Family Early Career Professor and assistant professor of mechanical and biomedical engineering.

This newly developed membrane does the same, but unlike conventional filters, this one does not separate objects by size. Instead, it responds to an object’s kinetic, or movement, energy.

“Typically, a smaller object is associated with lower kinetic energy due to its smaller mass,” Wong said. “So, the larger object with a higher kinetic energy will pass through the membrane, while the smaller object with lower kinetic energy will be retained.”

In addition, the membrane wraps around the object as it passes through, allowing the membrane to completely self-heal over the top of the object passing through it.

In its simplest form, the membrane can be created with water and a substance that stabilizes the interface between liquid and air, and has a structure similar to that of a biological cell membrane. To create the initial prototype, the team used a simple soap film. The components could then be modified and optimized to serve unique purposes, such as enhanced mechanical robustness, antibacterial properties, or odor-neutralization.

“You could add components that make the membrane last longer or components that allow it to block certain gases,” Boschitsch explained. “There are endless potential additives to choose from to tailor a membrane to the application of interest.”

Looking ahead, the researchers envision any number of creative, real-world applications for the membrane. If doctors need to perform open surgery without a clean operating room, a potential situation in remote areas or on military battlefields, this material could act as a surgical film to help replicate the clean environment needed to safely operate.

Not only could the membrane serve as a particle barrier, but the self-healing properties would also allow medical devices such as surgical tools to pass through while contaminants stay out.

“The membrane filter could potentially prevent germs, dust or allergens from reaching an open wound, while still allowing a doctor to perform surgery safely,” Wong said. “This membrane could make this possible.”

The research may also impact developing regions where there are sanitation concerns.

“One billion people in the world still openly defecate for many reasons, one being that latrines smell bad,” Boschitsch explained. “But if this could be applied to those toilets, it could allow solid waste to pass through the membrane, while the odor-causing gases will remain trapped.”

It is the potential for real-world impact that inspires the team.

“I’ve always been interested in developing technologies that can directly help people,” Boschitsch said. “Making something that can address a challenge facing humanity, in a developing country for example, is something I find meaningful.”

Looking to the future, the team plans to further develop the membrane with enhanced functions, and to collaborate with other researchers to test and adapt this membrane for practical applications. “The sky is really the limit,” Wong said.

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Materials provided by Penn State. Original written by Erin Cassidy Hendrick. Note: Content may be edited for style and length.

The controllable shape-shifting material, described today in the journal Science Advances, could have broad applications for manufacturing, robotics, biomedical devices and artificial muscles.

“The ability to form materials that can repeatedly oscillate back and forth between two independent shapes by exposing them to light will open up a wide range of new applications and approaches to areas such as additive manufacturing, robotics and biomaterials,” said Christopher Bowman, senior author of the new study and a Distinguished Professor in CU Boulder’s Department of Chemical and Biological Engineering (CHBE).

Previous efforts have used a variety of physical mechanisms to alter an object’s size, shape or texture with programmable stimuli. However, such materials have historically been limited in size or extent and the object state changes have proven difficult to fully reverse.

The new CU Boulder material achieves readily programmable two-way transformations on a macroscopic level by using liquid crystal elastomers (LCEs), the same technology underlying modern television displays. The unique molecular arrangement of LCEs make them susceptible to dynamic change via heat and light.

To solve this, the researchers installed a light-activated trigger to LCE networks that can set a desired molecular alignment in advance by exposing the object to particular wavelengths of light. The trigger then remains inactive until exposed to the corresponding heat stimuli. For example, a hand-folded origami swan programmed in this fashion will remain folded at room temperature. When heated to 200 degrees Fahrenheit, however, the swan relaxes into a flat sheet. Later, as it cools back to room temperature, it will gradually regain its pre-programmed swan shape.

The ability to change and then change back gives this new material a wide range of possible applications, especially for future biomedical devices that could become more flexible and adaptable than ever before.

“We view this as an elegant foundational system for transforming an object’s properties,” said Matthew McBride, lead author of the new study and a post-doctoral researcher in CHBE. “We plan to continue optimizing and exploring the possibilities of this technology.”

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In humans, defects in the protein can lead to skin diseases such as atopic dermatitis (a type of eczema), vitiligo (uneven skin coloration), skin cancer, and rosacea.

All vertebrate DNA, including the woolly mammoth genome, contains the TRPV3 gene. Though the mammoths lived in extremely cold environments, they descended from elephants that lived in the tropics. Researchers think that changes in the TRPV3 genes of mammoths may have helped them withstand lower temperatures.

Alexander Sobolevsky’s lab at Columbia University Irving Medical Center used a powerful imaging technique called cryo-electron microscopy to take pictures of TRPV3 molecules. Initial 2D images were collected by freezing the molecules in an extremely thin, clear layer of ice and bombarding them with electrons. The researchers then used computational tools to convert the 2D images into detailed molecular 3D models.

Image of human TRPV3 in the closed and open states viewed from outside the cell. Location of the region (N647) that is mutated in mammoths is highlighted. Images: Alexander Sobolevsky / CUIMC

This is the first time scientists have gotten a glimpse of TRPV3 in atomic detail. The researchers were able to get images of the protein in two states, revealing how the channel opens and closes to let ions flow into skin cells.

This exchange of ions prompts the body to react to sensations such as pain, itchiness, and changes in temperature. The group also discovered how a small molecule with anti-cancer properties called 2-APB interacts with and controls the function of this channel.

The structures in this study provide clues about how mutations in TRPV3 affect the channel’s ability to sense temperature and show that lipids — molecules that make up most of the cell membrane — contact the channel in several regions. Mammoth TRPV3 contains a mutation in one of these lipid-touching regions.

“Temperature affects the interaction of lipids and proteins,” Sobolevsky says. “A mutation in the woolly mammoth channel would most likely affect this interaction and could explain how these animals adapted to their cold environment.”

Researchers will use the structure to investigate how atomic changes to the protein cause it to malfunction in human diseases. “This study gives scientists a template they can use to design more effective drugs for treating these skin-related illnesses,” said Appu Singh, PhD, a postdoctoral fellow in the Sobolevsky lab and a first author of the paper.

Alexander Sobolevsky, PhD, is an associate professor of biochemistry and molecular biophysics at Columbia University Vagelos College of Physicians and Surgeons.

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OSIRIS-REx is NASA’s first mission to visit a near-Earth asteroid, survey the surface, collect a sample and deliver it safely back to Earth. The spacecraft has traveled approximately 1.1 billion miles (1.8 billion km) since its Sept. 8, 2016, launch and is scheduled to arrive at Bennu on Dec. 3.

“Now that OSIRIS-REx is close enough to observe Bennu, the mission team will spend the next few months learning as much as possible about Bennu’s size, shape, surface features, and surroundings before the spacecraft arrives at the asteroid,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. “After spending so long planning for this moment, I can’t wait to see what Bennu reveals to us.”

As OSIRIS-REx approaches the asteroid, the spacecraft will use its science instruments to gather information about Bennu and prepare for arrival. The spacecraft’s science payload comprises the OCAMS camera suite (PolyCam, MapCam, and SamCam), the OTES thermal spectrometer, the OVIRS visible and infrared spectrometer, the OLA laser altimeter, and the REXIS x-ray spectrometer.

During the mission’s approach phase, OSIRIS-REx will:

• regularly observe the area around the asteroid to search for dust plumes and natural satellites, and study Bennu’s light and spectral properties,;
• execute a series of four asteroid approach maneuvers, beginning on Oct. 1, slowing the spacecraft to match Bennu’s orbit around the Sun;
• jettison the protective cover of the spacecraft’s sampling arm in mid-October and subsequently extend and image the arm for the first time in flight; and
• use OCAMS to reveal the asteroid’s overall shape in late-October and begin detecting Bennu’s surface features in mid-November.

After arrival at Bennu, the spacecraft will spend the first month performing flybys of Bennu’s north pole, equator and south pole, at distances ranging between 11.8 and 4.4 miles (19 and 7 km) from the asteroid. These maneuvers will allow for the first direct measurement of Bennu’s mass as well as close-up observations of the surface. These trajectories will also provide the mission’s navigation team with experience navigating near the asteroid.

“Bennu’s low gravity provides a unique challenge for the mission,” said Rich Burns, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “At roughly 0.3 miles [500 meters] in diameter, Bennu will be the smallest object that any spacecraft has ever orbited.”

The spacecraft will extensively survey the asteroid before the mission team identifies two possible sample sites. Close examination of these sites will allow the team to pick one for sample collection, scheduled for early July 2020. After sample collection, the spacecraft will head back toward Earth before ejecting the Sample Return Capsule for landing in the Utah desert in Sept. 2023.

NASA’s Goddard Space Flight Center provides overall mission management, systems engineering and the safety and mission assurance for OSIRIS-REx. Dante Lauretta of the University of Arizona, Tucson, is the principal investigator, and the University of Arizona also leads the science team and the mission’s science observation planning and data processing. Lockheed Martin Space in Denver built the spacecraft and is providing flight operations. Goddard and KinetX Aerospace are responsible for navigating the OSIRIS-REx spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the agency’s New Frontiers Program for its Science Mission Directorate in Washington.

For more information on the mission, visit: https://www.nasa.gov/osiris-rex

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Leishmaniasis, the disease caused by the parasite, has been on the radar of scientists for a long time, not only because of efforts to find treatment, but because the parasite makes an ideal model for study. Hence, numerous immune mechanisms have been elucidated by researchers thanks to the disease, including at INRS. However, the quest for affordable and effective treatment continues. INRS professors Albert Descoteaux and Steven LaPlante have developed a new, cost-effective strategy to rapidly identify molecules capable of eliminating Leishmania, a disease which can disfigure, disable, or kill its victims, especially in tropical areas.

A Disease Affecting Numerous Species

“I have been studying this parasite for 30 years, and there is still a lot we do not understand,” says parasitologist Albert Descoteaux, who works to uncover the secrets of Leishmania, a genus encompassing some 20 single-celled species. In addition to its human victims, the parasite also targets some 70 other mammal species, according to the World Health Organization. Leishmania moves from an host to another by hitching a ride with tiny phlebotomine sandflies, which transmit the undesirable parasite when they bite.

According to the most recent estimates, 12 million people are currently affected by one form of leishmaniasis or another. There are three main forms: cutaneous, mucocutaneous, and visceral. “These are diseases that destroy lives — when they do not kill outright,” stresses Professor Descoteaux, adding that the pharmaceutical companies have little interest in developing treatments. “There is little commercial interest in neglected tropical diseases like leishmaniasis,” he points out. “It is the second-leading parasitic killer in the world, right behind malaria, yet there has been no real headway made on treatments in decades. There is currently no effective vaccine, and the available treatments all have major shortcomings, including serious side effects, high cost, and problems administering them in endemic areas.” He pauses before adding, “Unfortunately, as is the case with many other drugs, the parasite is also developing resistance. That is never good news.”

Albert Descoteaux, who is based at Centre INRS-Institut Armand-Frappier, is one of five INRS professors currently working on leishmaniasis. Their efforts to better understand the fundamental interaction between the parasite and its host account for one-third of all research activity on the disease in Canada, and their work is recognized worldwide.

Professor Steven LaPlante, who has been with INRS since 2015, specializes in drug discovery. With his colleague Albert Descoteaux, he has developed a project to identify new molecules that show promise for treating leishmaniasis. Their innovative approach is raising hopes of finding a more effective tool for developing drugs for leishmaniasis, but also for many other diseases.

The Challenge of Finding the Right Target

Having evolved its tactics and molecular machinery over millions of years, Leishmania has more than one trick up its sleeve. This is why there are so many obstacles to identifying molecules capable of eliminating the disease. For one thing, unicellular protists like Leishmania have more in common with mammal cells than with bacteria and viruses. “Like fungus, yeast, and worms, Leishmania are complex cells with a nucleus, and they have similarities to human cells,” notes the professor. “But they have taken a different evolutionary path, so there are lots of differences we need to identify and understand.”

Second, delivering a useful molecule to the parasite is a challenge. “Before it can kill Leishmania, the drug has to get past all kinds of barriers,” explains LaPlante.” It has to penetrate the infected cell without killing it or being too toxic. Then it has to reach and enter the protist to do its thing. Let’s just say that there are a lot of molecules to test before we find the right one for the job!”

Testing a lot of molecules is exactly the approach used by most researchers in the drug discovery process, but it takes extensive resources. Unfortunately, in the fight against leishmaniasis, there is little financial incentive for funding this kind of work. Yet given the prevalence of the disease worldwide, there are numerous calls for urgent action to find new treatments.

A Promising New Approach

This is the context in which the two INRS researchers joined forces, drawing on their combined expertise in biology (Albert Descoteaux) and medicinal chemistry (Steven LaPlante). LaPlante has access to a special small-molecule library from which he selected 1,604 molecules that had the best chances of reaching Leishmania in the macrophages and preventing it from completing its life cycle. Compared to the molecule libraries maintained by pharmaceutical companies — which can hold up to two million molecules — his library represents a very modest number but have special properties which makes it easily manageable within the confines of a university research lab.

“We dubbed our approach Fragment-Based Phenotypic Lead Discovery, or FPLD,” says Professor LaPlante. “It’s a combination of tried and tested methods that hadn’t previously been adapted for leishmaniasis. We start by administering very small molecules to cultured cells and then observe the impact on the infection.”

In medicinal chemistry, several phases are required to develop a drug with multiple characteristics. The ideal molecule for fighting an infection should be non-toxic to humans, easy to administer, capable of reaching the infectious agent, affordable to produce, and, obviously, effective against the pathogen in question.

As is the case when designing any everyday object, different components of a drug are selected to perform different jobs. The components in question are molecular fragments. The goal of the two INRS professors was to identify which of these could stop Leishmania in its tracks. The idea is that effective fragments can be combined with other components serving various purposes — stability, delivery, absorption, and so on — to improve efficacy and end up with a viable drug.

“We’ve been very fortunate to be able to rely on our collaborator NMX Research and Solutions Inc. and General Manager François Bilodeau who donated all the molecules we needed for our study. It’s a huge contribution,” notes Professor LaPlante. NMX designed the molecular fragments at the INRS business incubator, where the young startup is based.

A Painstaking Job

Yann Ayotte, lead author on the study recently published on the project, systematically — and very patiently — observed cultures treated with the fragments under the microscope, counting the number of parasites in the infected cells in order to compare them. The PhD student, who is currently continuing his research in Professor LaPlante’s lab, first joined the project as an intern in Albert Descoteaux’s lab at the end of his undergraduate degree. The two professors are quick to praise his outstanding dedication to his work.

After numerous experiments, the highly targeted screening of a small number of molecules allowed the team to identify two families of molecules showing high efficacy against Leishmania: indole and indazole derivatives. A dozen molecules have shown good potential, a very high number compared to other screening techniques.

Is there a new drug on the horizon? “For now, we are still at the very beginning of the process,” says Professor Descoteaux. “And you can’t skip any steps!” adds LaPlante. First, it’s essential to understand why the molecules have a leishmanicidal effect, a task that will keep Professor Descoteaux busy for a good while yet. In the mean time, the active molecule can be improved upon and “dressed up” with other appendages in order to fulfil all the criteria of an effective treatment — a job for Professor LaPlante and his team.

A Broader Vision

For Steven LaPlante, the most successful aspect of the project so far has been to show that a university lab can help identify potential new avenues for treatment. Pharmaceutical research does not cover all diseases or types of intervention, and from this perspective, academia can also play an important role.

The work of the team garnered enough enthusiasm that the journal ChemMedChem, published by ChemPubSoc Europe, a partnership of European chemical societies, rated it as a “Very Important Paper” and put it on the cover of the issue in which it appeared.

What will the study on the modes of action of the molecules identified at INRS reveal? “Research on Leishmania has lifted the veil on several properties of immune system we would not have been able to observe any other way,” affirms Professor Descoteaux. “Every time there is a new avenue to explore, we add to our knowledge on the immune system and on the biology of this parasite. Even if a new drug is still a long way away, these molecules will help us hone our understanding of the disease, which will keep us busy for years to come.”