Sensing the Odor Molecules on Graphene Surface Layered with Self-Assembled Peptides

Graphene-based olfactory sensors that can detect odor molecules based on the design of peptide sequences were recently demonstrated by researchers at Tokyo Tech. The findings indicated that graphene field-effect transistors (GFETs) functionalized with designable peptides can be used to develop electronic devices that mimic olfactory receptors and emulate the sense of smell by selectively detecting odor molecules.

Olfactory sensing or odor sensing is an integral part of many industries including healthcare, food, cosmetics, and environmental monitoring. At present, the most commonly used technique for detecting and estimating odor molecules is gas chromatography–mass spectrometry (GC–MS). Though very effective, GC–MS has some limitations, such as its bulky setup and limited sensitivity. As a consequence, scientists have been looking for more sensitive and easy-to-use alternatives.

In recent years, graphene field-effect transistors (GFETs) have begun being used to develop highly sensitive and selective odor sensors by integrating with olfactory receptors, also known as electronic noses. The atomically flat surfaces and high electron mobility of graphene surfaces make GFETs ideal for adsorbing odor molecules. However, the application of GFET as electrical biosensors with the receptors is severely limited by factors, such as the fragility of receptors and the lack of alternative synthetic molecules that can function as olfactory receptors.

Why faces might not be as attention-grabbing as we think

Data from the study’s 30 participants revealed they looked at the faces of just 16 per cent of the people they walked past.
Photo Credit: John Cameron

Research combining wearable eye-tracking technology and AI body detection software suggests our eyes aren’t drawn to the faces of passers-by as much as previously thought.

Faces are key to everyday social interaction. Just a brief glance can give us important signals about someone’s emotional state, intentions and identity that helps us to navigate our social world.

But researchers studying social attention – how we notice and process the actions and behaviors of others in social contexts – have been mostly limited to lab-based studies where participants view social scenes on computer screens. Now, researchers from the School of Psychology at UNSW Science have developed a new approach that could enable more studies of social attention in natural settings.

The novel method correlates eye-movement data from wearable eye-tracking glasses with analysis from an automatic face and body detection algorithm to record when and where participants looked when fixating on other people. The methodology, detailed in the journal Scientific Reports, could have a range of future applications in settings from clinical research to sports science.

New, safe, and biodegradable compound blocks radiation

Hesham Zakali: The material developed by an international group of scientists could become an alternative to toxic lead, for example.
Photo Credit: Anastasia Kurshpel

Polylactic acid combined with tungsten trioxide effectively blocks gamma radiation, an international group of scientists including specialists from Russia (Ural Federal University), Saudi Arabia and Egypt has found. In the future, it will be possible to create safe and biodegradable screens for protection against low-energy radiation on the basis of the new material, the researchers believe. Such screens are used in medicine, agriculture and the food industry. A description of the material has been published in the journal Radiation Physics and Chemistry.

"Polylactic acid is a non-toxic polymer of natural origin. It is inexpensive and, importantly, can be broken down by microbes when placed in an industrial plant at high temperatures. Since lactic acid is regularly produced as a byproduct of metabolism in both plants and animals, polylactic acid and its degradation products are non-toxic and safe for the environment," explains Hesham Zakali, co-author of the development and Researcher at the Department of Experimental Physics at UrFU.

Harnessing the healing power within our cells

E. coli bacteria
Photo Credit: Public Domain 

University of Queensland researchers have identified a pathway in cells that could be used to reprogram the body’s immune system to fight back against both chronic inflammatory and infectious diseases.

Dr Kaustav Das Gupta and Professor Matt Sweet from UQ’s Institute for Molecular Bioscience discovered that a molecule derived from glucose in immune cells can both stop bacteria growing and dampen inflammatory responses.

Dr Das Gupta said the finding is a critical step towards future therapeutics that train immune cells.

“The effects of this molecule called ribulose-5-phosphate on bacteria are striking – it can cooperate with other immune factors to stop disease-causing strains of the E. coli bacteria from growing,” Dr Das Gupta said.

“It also reprograms the immune system to switch off destructive inflammation, which contributes to both life-threatening infectious diseases such as sepsis as well as chronic inflammatory diseases like respiratory diseases, chronic liver disease, inflammatory bowel disease, rheumatoid arthritis, heart disease, stroke, diabetes and dementia.”

Microelectronics give researchers a remote control for biological robots

Remotely controlled miniature biological robots have many potential applications in medicine, sensing and environmental monitoring.   
Photo Credit: Yongdeok Kim

First, they walked. Then, they saw the light. Now, miniature biological robots have gained a new trick: remote control.

The hybrid “eBiobots” are the first to combine soft materials, living muscle and microelectronics, said researchers at the University of Illinois Urbana-Champaign, Northwestern University and collaborating institutions. They described their centimeter-scale biological machines in the journal Science Robotics.

“Integrating microelectronics allows the merger of the biological world and the electronics world, both with many advantages of their own, to now produce these electronic biobots and machines that could be useful for many medical, sensing and environmental applications in the future,” said study co-leader Rashid Bashir, an Illinois professor of bioengineering and dean of the Grainger College of Engineering.

New ‘chain mail’ material of interlocking molecules is tough, flexible and easy to make

The individual building blocks of a catenane are polyhedral molecules — a type of adamantane — that link arms to form a 2D mesh or 3D network that is sturdy but flexible.
Illustration Credit: Tianqiong Ma, UC Berkeley

University of California, Berkeley, chemists have created a new type of material from millions of identical, interlocking molecules that for the first time allows the synthesis of extensive 2D or 3D structures that are flexible, strong and resilient, like the chain mail that protected medieval knights.

The material, called an infinite catenane, can be synthesized in a single chemical step.

French chemist Jean-Pierre Sauvage shared the 2016 Nobel Prize in Chemistry for synthesizing the first catenane — two linked rings. These structures served as the foundation for making molecular structures capable of moving, which are often referred to as molecular machines.

But the chemical synthesis of catenanes has remained laborious. Adding each additional ring to a catenane requires another round of chemical synthesis. In the 24 years since Sauvage created a two-ring catenane, chemists have achieved, at most, a mere 130 interwoven rings in quantities too small to see without an electron microscope.

Cyborg Cells Could Be Tools for Health and Environment

UC Davis biomedical engineers have created semi-living “cyborg cells” that have many of the capabilities of living cells but are unable to divide and grow. The cells could have applications in medicine and environmental cleanup.
Illustration Credit: Cheemeng Tan, UC Davis.

Biomedical engineers at the University of California, Davis, have created semi-living “cyborg cells.” Retaining the capabilities of living cells, but unable to replicate, the cyborg cells could have a wide range of applications, from producing therapeutic drugs to cleaning up pollution. The work was published in Advanced Science.

Synthetic biology aims to engineer cells that can carry out novel functions. There are essentially two approaches in use, said Cheemeng Tan, associate professor of biomedical engineering at UC Davis and senior author on the paper. One is to take a living bacterial cell and remodel its DNA with new genes that give it new functions. The other is to create an artificial cell from scratch, with a synthetic membrane and biomolecules.

The first approach, an engineered living cell, has great flexibility but is also able to reproduce itself, which may not be desirable. A completely artificial cell cannot reproduce but is less complex and only capable of a limited range of tasks.

Data Reveal a Surprising Preference in Particle Spin Alignment

New data show that local fluctuations in the nuclear strong force may influence the spin orientation of particles called phi mesons (made of two quarks held together by the exchange of gluons).
Illustration Credit: Brookhaven National Laboratory

Given the choice of three different “spin” orientations, certain particles emerging from collisions at the Relativistic Heavy Ion Collider (RHIC), an atom smasher at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, appear to have a preference. As described in a paper just published in Nature by RHIC’s STAR collaboration, the results reveal a preference in global spin alignment of particles called phi mesons. Conventional mechanisms—such as the magnetic field strength or the swirliness of the matter generated in the particle collisions—cannot explain the data. But a new model that includes local fluctuations in the nuclear strong force can.

“It could be that the strong force fluctuations are the missing factor. Previously we hadn’t realized the strong force can influence particle spin in this way,” said Aihong Tang, a STAR physicist at Brookhaven who was involved in the analysis.

This explanation is still subject to debate and further verification is needed, the STAR physicists say. But if it proves to be true, “these measurements give us a way to gauge how large the local fluctuations in the strong force are. They provide a new avenue to study the strong force from a different perspective,” Tang said.

Boeing Awarded NASA Sustainable Flight Demonstrator Contract

SFD Rendering
NASA has selected Boeing and its industry team to lead the development and flight testing of a full-scale Transonic Truss-Braced Wing (TTBW) demonstrator airplane.
Image Credit: Boeing

NASA has selected Boeing and its industry team to lead the development and flight testing of a full-scale Transonic Truss-Braced Wing (TTBW) demonstrator airplane.

The technologies demonstrated and tested as part of the Sustainable Flight Demonstrator (SFD) program will inform future designs and could lead to breakthrough aerodynamics and fuel efficiency gains.

When combined with expected advancements in propulsion systems, materials and systems architecture, a single-aisle airplane with a TTBW configuration could reduce fuel consumption and emissions up to 30% relative to today's most efficient single-aisle airplanes, depending on the mission. The SFD program aims to advance the civil aviation industry's commitment to reaching net zero carbon emissions by 2050, as well as the goals set forth in the White House's U.S. Aviation Climate Action Plan.

Artifacts, Begone! NIST Improves Its Flagship Device for Measuring Mass

For the first time, scientists have integrated a quantum resistance standard directly into mass measurements made with the one-of-a-kind NIST-4 Kibble balance. Using the quantum standard in this way increases the accuracy of the measurements. This animation shows how the new quantum resistance standard, called QHARS, works. The QHARS device uses a sheet of graphene (a single layer of carbon atoms) attached to superconducting electrical contacts. When cooled to low temperature and placed in a strong magnetic field, electrons in the graphene begin moving in closed loops, a phenomenon known as the quantum Hall effect. This behavior results in the graphene having a specific resistance, providing an absolute reference for measuring current in the NIST-4 Kibble balance. 
Video Credit: Sean Kelley/NIST

In a brightly lit subterranean lab at the National Institute of Standards and Technology (NIST) sits a room-sized electromechanical machine called the NIST-4 Kibble balance.

The instrument can already measure the mass of objects of roughly 1 kilogram, about as heavy as a quart of milk, as accurately as any device in the world. But now, NIST researchers have further improved their Kibble balance’s performance by adding to it a custom-built device that provides an exact definition of electrical resistance. The device is called the quantum Hall array resistance standard (QHARS), and it consists of a set of several smaller devices that use a quirk of quantum physics to generate extremely precise amounts of electrical resistance. The researchers describe their work in a Nature Communications paper.