Facebook Begins Rollout of Data Use Checkup to Facebook Platform Developers

In an effort to further protect user privacy, and given past failures in this area, Facebook has recently simplified the company’s platform terms and developer policies in hopes that this will improve adherence to guidelines. To support these goals Facebook has announced the rollout of Data Use Checkup, an annual process for developers that validates data usage.

This new process, which is supported by a self-service tool, was first announced in April of 2020 and will require developers to use check each application they manage for adherence to company standards. Developers will have 60 days to comply with this standard before losing access to APIs.

The rollout of this program will be gradual and developers will begin to be notified over the next several months. The announcement of the rollout notes that developers will be notified “via a developer alert, an email to the registered contact, and in your Task List within the App Dashboard.” To simplify the process for developers that manage multiple apps, Facebook is allowing batch processing via an interface that facilitates this action, although developers will still be required to check each apps permissions.

Developers can check the App Dashboard to verify if they are able to enroll in the program at this time. 

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Author: <a href="">KevinSundstrom</a>


Scientists take new spin on quantum research

Army researchers discovered a way to further enhance quantum systems to provide Soldiers with more reliable and secure capabilities on the battlefield.

Specifically, this research informs how future quantum networks will be designed to deal with the effects of noise and decoherence, or the loss of information from a quantum system in the environment.

As one of the U.S. Army’s priority research areas in its Modernization Strategy, quantum research will help transform the service into a multi-domain force by 2035 and deliver on its enduring responsibility as part of the joint force providing for the defense of the United States.

“Quantum networking, and quantum information science as a whole, will potentially lead to unsurpassed capabilities in computation, communication and sensing,” said Dr. Brian Kirby, researcher at the U.S. Army Combat Capabilities Development Command’s Army Research Laboratory. “Example applications of Army interest include secure secret sharing, distributed network sensing and efficient decision making.”

This research effort considers how dispersion, a very common effect found in optical systems, impacts quantum states of three or more particles of light.

Dispersion is an effect where a pulse of light spreads out in time as it is transmitted through a medium, such as a fiber optic. This effect can destroy time correlations in communication systems, which can result in reduced data rates or the introduction of errors.

To understand this, Kirby said, consider the situation where two light pulses are created simultaneously and the goal is to send them to two different detectors so that they arrive at the same time. If each light pulse goes through a different dispersive media, such as two different fiber optic paths, then each pulse will be spread in time, ultimately making the arrival time of the pulses less correlated.

“Amazingly, it was shown that the situation is different in quantum mechanics,” Kirby said. “In quantum mechanics, it is possible to describe the behavior of individual particles of light, called photons. Here, it was shown by research team member Professor James Franson from the University of Maryland, Baltimore County, that quantum mechanics allows for certain situations where the dispersion on each photon can actually cancel out so that the arrival times remain correlated.”

The key to this is something called entanglement, a strong correlation between quantum systems, which is not possible in classical physics, Kirby said.

In this new work, Nonlocal Dispersion Cancellation for Three or More Photons, published in the peer-reviewed Physical Review A, the researchers extend the analysis to systems of three or more entangled photons and identify in what scenarios quantum systems outperform classical ones. This is unique from similar research as it considers the effects of noise on entangled systems beyond two-qubits, which is where the primary focus has been.

“This informs how future quantum networks will be designed to deal with the effects of noise and decoherence, in this case, dispersion specifically,” Kirby said.

Additionally, based on the success of Franson’s initial work on systems of two-photons, it was reasonable to assume that dispersion on one part of a quantum system could always be cancelled out with the proper application of dispersion on another part of the system.

“Our work clarifies that perfect compensation is not, in general, possible when you move to entangled systems of three or more photons,” Kirby said. “Therefore, dispersion mitigation in future quantum networks may need to take place in each communication channel independently.”

Further, Kirby said, this work is valuable for quantum communications because it allows for increased data rates.

“Precise timing is required to correlate detection events at different nodes of a network,” Kirby said. “Conventionally the reduction in time correlations between quantum systems due to dispersion would necessitate the use of larger timing windows between transmissions to avoid confusing sequential signals.”

Since Kirby and his colleagues’ new work describes how to limit the uncertainty in joint detection times of networks, it will allow subsequent transmissions in quicker succession.

The next step for this research is to determine if these results can be readily verified in an experimental setting.

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Machine learning research may help find new tungsten deposits in SW England

Geologists have developed a machine learning technique that highlights the potential for further deposits of the critical metal tungsten in SW England.

Tungsten is an essential component of high-performance steels but global production is strongly influenced by China and western countries are keen to develop alternative sources.

The work, published in the leading journal Geoscience Frontiers, has been led by Dr Chris Yeomans, from the Camborne School of Mines, and involved geoscientists from the University of Nottingham, Geological Survey of Finland (GTK) and the British Geological Survey.

The research applies machine learning to multiple existing datasets to examine the geological factors that have resulted in known tungsten deposits in SW England.

These findings are then applied across the wider region to predict areas where tungsten mineralisation is more likely and might have previously been overlooked. The same methodology could be applied to help in the exploration for other metals around the world.

Dr Yeomans, a Postdoctoral Research Fellow at the Camborne School of Mines, based at the University of Exeter’s Penryn Campus in Cornwall said: “We’re really pleased with the methodology developed and the results of this study.

“SW England is already the focus of UK mineral exploration for tungsten but we wanted to demonstrate that new machine learning approaches may provide additional insights and highlight areas that might otherwise be overlooked.”

SW England hosts the fourth biggest tungsten deposit in the world (Hemerdon, near Plympton), that resulted in the UK being the sixth biggest global tungsten producer in 2017; the mine is currently being re-developed by Tungsten West Limited.

The Redmoor tin-tungsten project, being developed by Cornwall Resources Limited, has also been identified as being a potentially globally significant mineral deposit.

The new study suggests that there may be a wider potential for tungsten deposits and has attracted praise from those currently involved in the development of tungsten resources in SW England.

James McFarlane, from Tungsten West, said: “Tungsten has only been of economic interest in the last 100 years or so, during which exploration efforts for this critical metal have generally been short-lived.

“As such is very encouraging to see work that aims to holistically combine the available data to develop a tungsten prospectivity model in an area that has world-class potential.”

Brett Grist, from Cornwall Resources added: “Our own work has shown that applying modern techniques can reveal world-class deposits in this historic and globally-significant mining district.

“Dr Yeomans’ assertion, that the likelihood of new discoveries of tungsten mineralisation may be enhanced by a high-resolution gravity survey, is something in which we see great potential.

“Indeed, such a programme could stimulate the new discovery of economically significant deposits of a suite of critical metals, here in the southwest of the UK, for years to come.”

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Materials provided by University of Exeter. Note: Content may be edited for style and length.

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Seek Thermal Adds API for its Temperature Screening Products

To further develop effective and customized solutions for Seek Scan, a low-cost thermal temperature screening solutions meeting FDA guidelines during the COVID-19 public health emergency, Seek Thermal today announced it has made APIs available for access control, VMS and other integrated network capabilities.

The Seek Scan thermal imaging system is specifically designed and calibrated to quickly automate body temperature screening using skin temperature as a proxy, while enabling social distancing protocols. In a few seconds, the system automatically detects a face for measurement and displays an alert if the readings are warmer than the customizable alarm temperature. The thermal scanning system follows FDA guidelines by meeting the accuracy specification, including a reference heat source (black body), and by being made for single person screening at a fixed distance.

The new API capabilities allow Seek Scan to be accessible anywhere on a network, enabling access control systems, video management systems, integrators, and business owners to manage and access their Seek Scan systems and solutions. Now, integrators can implement Seek Scan temperature screening to send alarm events, trigger access control and video management systems as well as pull and present historical data to integrate multiple Seek Scan units into one enterprise solution.

Specific integrated functionality could include:

  • Accessing entry doors following scans
  • Triggering access control and video management systems
  • Allowing custom designed solutions utilizing Seek Scan hardware
  • Sending pass/fail scan messages and alarm events
  • Flagging video when a scan occurs

“The demand for temperature screening and integrated API solutions has been growing rapidly,” said Mike Muench, CEO and President of Seek Thermal. “As businesses, institutions and organizations seek to provide safer environments in an increasingly uncertain time, we recognize the needs of our customers don’t stop with the contactless screening technology itself – the new and expanded integration capabilities of Seek Scan offer additional control, convenience and confidence.”

Whether the desire is to unlock a door with a temperature scan, capture an image or flag a video when a scan occurs, or send email alerts, Seek Thermal has made it easy for integrators to connect temperature screening to their network using its JSON based APIs to do all that and more.

With Seek Scan, the company has developed customer relationships with a diverse group of leading organizations, including manufacturers, government institutions, hospitals and medical facilities, office buildings, hotels and hospitality providers, schools and universities, first responders and professional sports organizations.

Seek Thermal will continue to release features, capabilities and protocols to enhance its API offering.

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Author: <a href="">ProgrammableWeb PR</a>


Metasurface design methods can make LED light act more like lasers

UC Santa Barbara researchers continue to push the boundaries of LED design a little further with a new method that could pave the way toward more efficient and versatile LED display and lighting technology.

In a paper published in Nature Photonics, UCSB electrical and computer engineering professor Jonathan Schuller and collaborators describe this new approach, which could allow a wide variety of LED devices — from virtual reality headsets to automotive lighting — to become more sophisticated and sleeker at the same time.

“What we showed is a new kind of photonic architecture that not only allows you to extract more photons, but also to direct them where you want,” said Schuller. This improved performance, he explained, is achieved without the external packaging components that are often used to manipulate the light emitted by LEDs.

Light in LEDs is generated in the semiconductor material when excited, negatively charged electrons traveling along the semiconductor’s crystal lattice meet positively-charged holes (an absence of electrons) and transition to a lower state of energy, releasing a photon along the way. Over the course of their measurements, the researchers found that a significant amount of these photons were being generated but were not making it out of the LED.

“We realized that if you looked at the angular distribution of the emitted photon before patterning, it tended to peak at a certain direction that would normally be trapped within the LED structure,” Schuller said. “And so we realized that you could design around that normally trapped light using traditional metasurface concepts.”

The design they settled upon consists of an array of 1.45-micrometer long gallium nitride (GaN) nanorods on a sapphire substrate, in which quantum wells of indium gallium nitride were embedded, to confine electrons and holes and thus emit light. In addition to allowing more light to leave the semiconductor structure, the process polarizes the light, which co-lead author Prasad Iyer said, “is critical for a lot of applications.”

Nanoscale Antennae

The idea for the project came to Iyer a couple of years ago as he was completing his doctorate in Schuller’s lab, where the research is focused on photonics technology and optical phenomena at subwavelength scales. Metasurfaces — engineered surfaces with nanoscale features that interact with light — were the focus of his research.

“A metasurface is essentially a subwavelength array of antennas,” said Iyer, who previously was researching how to steer laser beams with metasurfaces. He understood that typical metasurfaces rely on the highly directional properties of the incoming laser beam to produce a highly directed outgoing beam.

LEDs, on the other hand, emit spontaneous light, as opposed to the laser’s stimulated, coherent light.

“Spontaneous emission samples all the possible ways the photon is allowed to go,” Schuller explained, so the light appears as a spray of photons traveling in all possible directions. The question was could they, through careful nanoscale design and fabrication of the semiconductor surface, herd the generated photons in a desired direction?

“People have done patterning of LEDs previously,” Iyer said, but those efforts invariably split the into multiple directions, with low efficiency. “Nobody had engineered a way to control the emission of light from an LED into a single direction.”

Right Place, Right Time

It was a puzzle that would not have found a solution, Iyer said, without the help of a team of expert collaborators. GaN is exceptionally difficult to work with and requires specialized processes to make high-quality crystals. Only a few places in the world have the expertise to fabricate the material in such exacting design.

Fortunately, UC Santa Barbara, home to the Solid State Lighting and Energy Electronics Center (SSLEEC), is one of those places. With the expertise at SSLEEC and the campus’s world-class nanofabrication facility, the researchers designed and patterned the semiconductor surface to adapt the metasurface concept for spontaneous light emission.

“We were very fortunate to collaborate with the world experts in making these things,” Schuller said.

Research on this project also was conducted by Ryan A. DeCrescent (co-lead author), Yahya Mohtashami, Guillaume Lhereux, Nikita Butakov, Abdullah Alhassan, Claude Weisbuch, Shuji Nakamura and Steven P. DenBaars, all from UCSB.

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Suprema Launches G-SDK for gRPC Security Integration

Suprema, a provider of security and biometrics technology and equipment, has launched a new SDK that is designed to further simplify integration with third-party ID management software. The all-new G-SDK is based on gRPC.

The Suprema G-SDK provides support for languages including Java, C#, Python, Node.js, and Go. The announcement of this SDK comes alongside a new device gateway and gRPC server to support the workflow. 

Suprema noted a significant difference between this new SDK and the existing device SDK:

“One of the biggest advantages of G-SDK compare to Device SDK is that it supports various languages. For the last years, Device SDK users have had difficulty using development language other than C++ or C# which is in the sample code.”

Interested developers can check out the company’s support page for more information. 

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Author: <a href="">KevinSundstrom</a>


Cobalt supply can meet demand for electric vehicle and electronics batteries

Greater use of electric vehicles might be good for the environment, but further growth hinges on continued availability of critical battery components such as cobalt. Cell phones and other electronics also depend on the element’s availability. Supplies of the metal are adequate in the short term, but shortages could develop down the road if refining and recycling aren’t ramped up or made more efficient, according to research published in ACS’ Environmental Science & Technology.

Roughly 60% of mined cobalt is sourced from the Democratic Republic of Congo (DRC). The element is often recovered as a byproduct from mining copper and nickel, meaning that demand and pricing for those other metals affects the availability of cobalt. Half of the current supply of cobalt is incorporated into cathodes for lithium-ion batteries, and many of those batteries are used in consumer electronics and electric vehicles. Demand for these vehicles and their batteries is growing swiftly: In 2018, the global electric car fleet numbered in excess of 5.1 million, up 2 million from the prior year, according to the International Energy Agency. Elsa Olivetti and coworkers wanted to find out if planned cobalt expansions could keep pace with this brisk growth.

To determine potential cobalt supply and demand through 2030, the researchers analyzed variables, including electric vehicle demand; cobalt mining, refining and recycling capacity; battery chemistry trends; socioeconomic and political trends; and the feasibility of substituting other materials for cobalt. These variables could be affected by political instability in DRC, policy decisions favoring electric vehicles, disruptions in China (which refines around half of the cobalt supply), and fluctuations in copper and nickel prices. The researchers concluded that cobalt supply is adequate in the short-term. They estimate supply will reach 320-460 thousand metric tons by 2030, while demand will reach 235-430 thousand metric tons. The team recommends that the industry invest in additional efficient refining and recycling capacity, so it can continue to meet demand.

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Materials provided by American Chemical Society. Note: Content may be edited for style and length.

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Coin-sized smart insulin patch, potential diabetes treatment

UCLA bioengineers and colleagues at UNC School of Medicine and MIT have further developed a smart insulin-delivery patch that could one day monitor and manage glucose levels in people with diabetes and deliver the necessary insulin dosage. The adhesive patch, about the size of a quarter, is simple to manufacture and intended for once-a-day use.

The study, published in Nature Biomedical Engineering, describes research conducted on mice and pigs. The research team, led by Zhen Gu, PhD, professor of bioengineering at the UCLA Samueli School of Engineering, is applying for FDA approval of clinical trials in humans. Gu and colleagues conducted the initial successful tests of the smart insulin patch in mice in 2015 in North Carolina.

“Our main goal is to enhance health and improve the quality of life for people who have diabetes,” said Gu, a former professor in the UNC/NCSU Joint Department of Biomedical Engineering. “This smart patch takes away the need to constantly check one’s blood sugar and then inject insulin if and when it’s needed. It mimics the regulatory function of the pancreas but in a way that’s easy to use.”

The adhesive patch monitors blood sugar, or glucose. It has doses of insulin pre-loaded in very tiny microneedles, less than one-millimeter in length that deliver medicine quickly when the blood sugar levels reach a certain threshold. When blood sugar returns to normal, the patch’s insulin delivery also slows down. The researchers said the advantage is that it can help prevent overdosing of insulin, which can lead to hypoglycemia, seizures, coma or even death.

“It has always been a dream to achieve insulin-delivery in a smart and convenient manner,” said study co-author John Buse, MD, PhD, director of the UNC Diabetes Center and the North Carolina Translational and Clinical Sciences (NC TraCS) Institute at the University of North Carolina at Chapel Hill School of Medicine. “This smart insulin patch, if proven safe and effective in human trials, would revolutionize the patient experience of diabetes care.”

Insulin is a hormone naturally produced in the pancreas helps the body regulate glucose, which comes from food-consumption and provides the body with energy. Insulin is the molecular key that helps move glucose from the bloodstream to the cells for energy and storage. Type 1 diabetes occurs when a person’s body does not naturally produce insulin. Type 2 diabetes occurs when the body does not efficiently use the insulin that is produced. In either case, a regular dosage of insulin is prescribed to manage the disease, which affects more than 400 million people worldwide.

The treatment for the disease hasn’t changed much in decades in most of the world. Patients with diabetes draw their blood using a device that measures glucose levels. They then self-administer a necessary dose of insulin. The insulin can be injected with a needle and syringe, a pen-like device, or delivered by an insulin pump, which is a portable cellphone-sized instrument attached to the body through a tube with a needle on the end. A smart insulin patch would sense the need for insulin and deliver it.

The microneedles used in the patch are made with a glucose-sensing polymer that’s encapsulated with insulin. Once applied on the skin, the microneedles penetrate under the skin and can sense blood sugar levels. If glucose levels go up, the polymer is triggered to release the insulin. Each microneedle is smaller than a regular needle used to draw blood and do not reach as deeply, so the patch is less painful than a pin prick. Each microneedle penetrates about a half millimeter below the skin, which is sufficient to deliver insulin into the body.

In the experiments, one quarter-sized patch successfully controlled glucose levels in pigs with type I diabetes for about 20 hours. The pigs weighed about 55 pounds on average.

“I am glad the team could bring this smart insulin patch one more step close to reality, and we look forward to hopefully seeing it move forward to someday help people with diabetes,” said Robert Langer, ScD, the David H. Koch Institute Professor at MIT and one of the paper’s co-authors.

The technology has been accepted into the U.S. Food and Drug Administration’s Emerging Technology Program, which provides assistance to companies during the regulatory process. The researchers are applying for FDA approval for human clinical trials, which they anticipate could start within a few years. The team envisioned that the smart microneedle patch could be adapted with different drugs to manage other medical conditions as well.

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Method detects defects in 2D materials for future electronics, sensors

To further shrink electronic devices and to lower energy consumption, the semiconductor industry is interested in using 2D materials, but manufacturers need a quick and accurate method for detecting defects in these materials to determine if the material is suitable for device manufacture. Now a team of researchers has developed a technique to quickly and sensitively characterize defects in 2D materials.

Two-dimensional materials are atomically thin, the most well-known being graphene, a single-atom-thick layer of carbon atoms.

“People have struggled to make these 2D materials without defects,” said Mauricio Terrones, Verne M. Willaman Professor of Physics, Penn State. “That’s the ultimate goal. We want to have a 2D material on a four-inch wafer with at least an acceptable number of defects, but you want to evaluate it in a quick way.”

The researchers’ — who represent Penn State, Northeastern University, Rice University and Universidade Federal de Minas Gerais in Brazil — solution is to use laser light combined with second harmonic generation, a phenomenon in which the frequency of the light shone on the material reflects at double the original frequency. They add dark field imaging, a technique in which extraneous light is filtered out so that defects shine through. According to the researchers, this is the first instance in which dark field imaging was used, and it provides three times the brightness of the standard bright field imaging method, making it possible to see types of defects previously invisible.

“The localization and identification of defects with the commonly used bright field second harmonic generation is limited because of interference effects between different grains of 2D materials,” said Leandro Mallard, a senior author on a recent paper in Nano Letters and a professor at Universidade Federal de Minas Gerais. “In this work we have shown that by the use of dark field SHG we remove the interference effects and reveal the grain boundaries and edges of semiconducting 2D materials. Such a novel technique has good spatial resolution and can image large area samples that could be used to monitor the quality of the material produced in industrial scales.”

Vincent H. Crespi, Distinguished Professor of Physics, Materials Science and Engineering, and Chemistry, Penn State, added, “Crystals are made of atoms, and so the defects within crystals — where atoms are misplaced — are also of atomic size.

“Usually, powerful, expensive and slow experimental probes that do microscopy using beams of electrons are needed to discern such fine details in a material,” said Crespi. “Here, we use a fast and accessible optical method that pulls out just the signal that originates from the defect itself to rapidly and reliably find out how 2D materials are stitched together out of grains oriented in different ways.”

Another coauthor compared the technique to finding a particular zero on a page full of zeroes.

“In the dark field, all the zeroes are made invisible so that only the defective zero stands out,” said Yuanxi Wang, assistant research professor at Penn State’s Materials Research Institute.

The semiconductor industry wants to have the ability to check for defects on the production line, but 2D materials will likely be used in sensors before they are used in electronics, according to Terrones. Because 2D materials are flexible and can be incorporated into very small spaces, they are good candidates for multiple sensors in a smartwatch or smartphone and the myriad of other places where small, flexible sensors are required.

“The next step would be an improvement of the experimental setup to map zero dimension defects — atomic vacancies for instance — and also extend it to other 2D materials that host different electronic and structural properties,” said lead author Bruno Carvalho, a former visiting scholar in Terrones’ group,

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Materials provided by Penn State. Note: Content may be edited for style and length.

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Self-assembled artificial microtubules developed

Simple LEGO bricks can be assembled to more complicated structures, which can be further associated into a wide variety of complex architectures, from automobiles, rockets, and ships to gigantic castles and amusement parks. Such an event of multi-step assembly, so-called ‘hierarchical self-assembly’, also happens in living organisms.

Professor Kimoon Kim (Department of Chemistry, POSTECH) and his research team (Center for Self-assembly and Complexity, Institute for Basic Science) discovered that a cucurbituril (1)-based host-guest complex polymerized into a linear polymer chain, which was further associated with each other into a hollow microtubule via van der Waals interactions arising from their shape self-complementarity. (2) Their novel findings are introduced in Angewandte Chemie International Edition.

Microtubules exist in living cells of plants and animals and they are essential in maintaining cellular structures, migration of cells, intracellular transport and more. In other words, essential cellular functions such as cellular divisions and intracellular transport cannot be performed when problems occur in formation or dissociation of microtubules.

These microtubules are formed via hierarchical self-assembly of globular proteins in nanometer size, tubulins (3), which grow into linear protofilaments.(4) Subsequently, these protofilaments are assembled together to build a multi-stranded tubular structure with a length over tens of micrometers.

Before their findings, many attempts have been made to mimic the self-assembly of microtubules in depth for years. However, the formation mechanism of natural microtubules at the molecular level is still ambiguous.

To make artificial microtubules, the research group utilized the cucurbituril-based host-guest complex with two thiol groups (5) attached at the both ends as a building block. This building block assembled into one-dimensional linear polymers by disulfide bond formation. Then, these polymers were laterally associated into a hollow cylindrical architecture similar to natural microtubules through van der Waals interactions. The formation of artificial microtubules was characterized by various spectroscopic and microscopic studies including X-ray diffraction at Pohang Light Source.

Especially, the research team found that the polymer chain became straight and stiff by itself, and eventually LEGO brick-like shape self-complementarity was emerged during the growth of polymer. Strikingly, the convex structures of one chain matched well with the concave parts of the neighboring chains, which allowed lateral association of polymer chains.

The first author of the paper, Wooseup Hwang explained, “Studies before our discovery were focused on mimicking architecture of microtubules. What differentiates our research from the conventional ones is that we attempt to mimic the formation mechanism of microtubules as well as architecture.”

Dr. Kangkyun Baek, the other co-corresponding author commented, “We are planning to extend our study to mimic dynamic behaviors and various biological functions of natural microtubules.” and “This novel approach based on the shape self-complementarity will make a step forward to understand the formation mechanism of natural microtubules, and offer new opportunities to explore unconventional hierarchical self-assemblies and novel functional materials.”

1. Cucurbituril Pumpkin-shaped chemical compounds were named cucurbituril because of its resemblance to a pumpkin which belongs to the Cucurbitaceae family. Glycoluril monomers are linked by methylene bridges and cucurbituril with seven glycoluril monomers is used in this research.

2. Shape self-complementarity A convex structure of a substance matches with a concave part of the other and can be assembled

3. Tubulin protein composing microtubules in cell

4. Protofilament protein filament that determines cellular structures and migration and constitutes a hollow cylindrical structure with nanometer diameter

5. Thiol group Sulfhydryl group. Two thiol groups are oxidized to form disulfide bond. Especially, it is located in cysteine residues and it plays an important role in constructing the secondary and tertiary structure of proteins by disulfide bonds.

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