Aurelia Butler

The technological advancement of optical lenses has long been a significant marker of human scientific achievement. Eyeglasses, telescopes, cameras, and microscopes have all literally and figuratively allowed us to see the world in a new light. Lenses are also a fundamental component of manufacturing nanoelectronics by the semiconductor industry.
One of the most impactful breakthroughs of lens technology in recent history has been the development of photonic metasurfaces — artificially engineered nano-scale materials with remarkable optical properties. Georgia Tech researchers at the forefront of this technology have recently demonstrated the first-ever electrically tunable photonic metasurface platform in a recent study published by Nature Communications.
“Metasurfaces can make the optical systems very thin, and as they become easier to control and tune, you’ll soon find them in cell phone cameras and similar electronic imaging systems,” said Ali Adibi, professor in the School of Electrical and Computer Engineering at the Georgia Institute of Technology.
The pronounced tuning measures achieved through the new platform represent a critical advancement towards the development of miniaturized reconfigurable metasurfaces. The results of the study have shown a record eleven-fold change in the reflective properties, a large range of spectral tuning for operation, and much faster tuning speed.
Heating Up Metasurfaces
Metasurfaces are a class of nanophotonic materials in which a large range of miniaturized elements are engineered to affect the transmission and reflection of light at different frequencies in a controlled way. More

Water is the secret ingredient in a simple way to create key components for solar cells, X-ray detectors and other optoelectronics devices.
The next generation of photovoltaics, semiconductors and LEDs could be made using perovskites — an exciting and versatile nanomaterial with a crystal structure.
Perovskites have already shown similar efficiency to silicon, are cheaper to make, and feature a tuneable bandgap, meaning the energy they are able to absorb, reflect or conduct can be changed to suit different purposes.
Ordinarily, water is kept as far away as possible during the process of creating perovskites. The presence of moisture can lead to defects in the materials, causing them to fall apart more quickly when they’re being used in a device.
That’s why perovskites for scientific research are often made via spin coating in the sealed environment of a nitrogen glove box.
Now, though, members of the ARC Centre of Excellence in Exciton Science have found a simple way to control the growth of phase-pure perovskite crystals by harnessing water as a positive factor. This liquid-based mechanism works at room temperature, so the approach remains cost effective. More

The “smart skin” developed by Anna Maria Coclite is very similar to human skin. It senses pressure, humidity and temperature simultaneously and produces electronic signals. More sensitive robots or more intelligent prostheses are thus conceivable.
The skin is the largest sensory organ and at the same time the protective coat of the human being. It “feels” several sensory inputs at the same time and reports information about humidity, temperature and pressure to the brain. For Anna Maria Coclite, a material with such multisensory properties is “a kind of ‘holy grail’ in the technology of intelligent artificial materials. In particular, robotics and smart prosthetics would benefit from a better integrated, more precise sensing system similar to human skin.” The ERC grant winner and researcher at the Institute of Solid State Physics at TU Graz has succeeded in developing the three-in-one hybrid material “smart skin” for the next generation of artificial, electronic skin using a novel process. The result of this pioneering research has now been published in the journal Advanced Materials Technologies.
As delicate as a fingertip
For almost six years, the team worked on the development of smart skin as part of Coclite’s ERC project Smart Core. With 2,000 individual sensors per square millimetre, the hybrid material is even more sensitive than a human fingertip. Each of these sensors consists of a unique combination of materials: an smart polymer in the form of a hydrogel inside and a shell of piezoelectric zinc oxide. Coclite explains: “The hydrogel can absorb water and thus expands upon changes in humidity and temperature. In doing so, it exerts pressure on the piezoelectric zinc oxide, which responds to this and all other mechanical stresses with an electrical signal.” The result is a wafer-thin material that reacts simultaneously to force, moisture and temperature with extremely high spatial resolution and emits corresponding electronic signals. “The first artificial skin samples are six micrometres thin, or 0.006 millimetres. But it could be even thinner,” says Anna Maria Coclite. In comparison, the human epidermis is 0.03 to 2 millimetres thick. The human skin perceives things from a size of about one square millimetre. The smart skin has a resolution that is a thousand times smaller and can register objects that are too small for human skin (such as microorganisms).
Material processing at the nanoscale
The individual sensor layers are very thin and at the same time equipped with sensor elements covering the entire surface. This was possible in a worldwide unique process for which the researchers combined three known methods from physical chemistry for the first time: a chemical vapour deposition for the hydrogel material, an atomic layer deposition for the zinc oxide and nanoprint lithography for the polymer template. The lithographic preparation of the polymer template was the responsibility of the research group “Hybrid electronics and structuring” headed by Barbara Stadlober. The group is part of Joanneum Research’s Materials Institute based in Weiz.
Several fields of application are now opening up for the skin-like hybrid material. In healthcare, for example, the sensor material could independently detect microorganisms and report them accordingly. Also conceivable are prostheses that give the wearer information about temperature or humidity, or robots that can perceive their environment more sensitively. On the path to application,smart skin scores with a decisive advantage: the sensory nanorods — the “smart core” of the material — are produced using a vapor-based manufacturing process. This process is already well established in production plants for integrated circuits, for example. The production of smart skin can thus be easily scaled and implemented in existing production lines.
The properties of smart skin are now being optimized even further. Anna Maria Coclite and her team — here in particular the PhD student Taher Abu Ali — want to extend the temperature range to which the material reacts and improve the flexibility of the artificial skin.
Story Source:
Materials provided by Graz University of Technology. Original written by Susanne Filzwieser. Note: Content may be edited for style and length. More

Engineering researchers have developed a new approach for implementing ransomware detection techniques, allowing them to detect a broad range of ransomware far more quickly than previous systems.
Ransomware is a type of malware. When a system is infiltrated by ransomware, the ransomware encrypts that system’s data — making the data inaccessible to users. The people responsible for the ransomware then extort the affected system’s operators, demanding money from the users in exchange for granting them access to their own data.
Ransomware extortion is hugely expensive, and instances of ransomware extortion are on the rise. The FBI reports receiving 3,729 ransomware complaints in 2021, with costs of more than $49 million. What’s more, 649 of those complaints were from organizations classified as critical infrastructure.
“Computing systems already make use of a variety of security tools that monitor incoming traffic to detect potential malware and prevent it from compromising the system,” says Paul Franzon, co-author of a paper on the new ransomware detection approach. “However, the big challenge here is detecting ransomware quickly enough to prevent it from getting a foothold in the system. Because as soon as ransomware enters the system, it begins encrypting files.” Franzon is Cirrus Logic Distinguished Professor of Electrical and Computer Engineering at North Carolina State University.
“There’s a machine-learning algorithm called XGBoost that is very good at detecting ransomware,” says Archit Gajjar, first author of the paper and a Ph.D. student at NC State. “However, when systems run XGBoost as software through a CPU or GPU, it’s very slow. And attempts to incorporate XGBoost into hardware systems have been hampered by a lack of flexibility — they focus on very specific challenges, and that specificity makes it difficult or impossible for them to monitor for the full array of ransomware attacks.
“We’ve developed a hardware-based approach that allows XGBoost to monitor for a wide range of ransomware attacks, but is much faster than any of the software approaches,” Gajjar says.
The new approach is called FAXID, and in proof-of-concept testing, the researchers found it was just as accurate as software-based approaches at detecting ransomware. The big difference was speed. FAXID was up to 65.8 times faster than software running XGBoost on a CPU and up to 5.3 times faster than software running XGBoost on a GPU.
“Another advantage of FAXID is that it allows us to run problems in parallel,” Gajjar says. “You could devote all of the dedicated security hardware’s resources to ransomware detection, and detect ransomware more quickly. But you could also allocate the security hardware’s computing power to separate problems. For example, you could devote a certain percentage of the hardware to ransomware detection and another percentage of the hardware to another challenge — such as fraud detection.”
“Our work on FAXID was funded by the Center for Advanced Electronics through Machine Learning (CAEML), which is a public-private partnership,” Franzon says. “The technology is already being made available to members of the center, and we know of at least one company that is making plans to implement it in their systems.”
The paper, “FAXID: FPGA-Accelerated XGBoost Inference for Data Centers using HLS,” is being presented at the 30th IEEE International Symposium on Field-Programmable Custom Computing Machines (FCCM), being held in New York City from May 15-18. The paper was co-authored by Priyank Kashyap, a Ph.D. student at NC State; Aydin Aysu, an assistant professor of electrical and computer engineering at NC State; and Sumon Dey and Chris Cheng of Hewlett Packard Enterprise.
The work was supported by CAEML, through National Science Foundation grant number CNS #16-244770, and CAEML member companies.
Story Source:
Materials provided by North Carolina State University. Original written by Matt Shipman. Note: Content may be edited for style and length. More

Crafty hackers can make a tool to eavesdrop on some 6G wireless signals in as little as five minutes using office paper, an inkjet printer, a metallic foil transfer and a laminator.
The wireless security hack was discovered by engineering researchers from Rice University and Brown University, who will present their findings and demonstrate the attack this week in San Antonio at ACM WiSec 2022, the Association for Computing Machinery’s annual conference on security and privacy in wireless and mobile networks.
“Awareness of a future threat is the first step to counter that threat,” said study co-author Edward Knightly, Rice’s Sheafor-Lindsay Professor of Electrical and Computer Engineering. “The frequencies that are vulnerable to this attack aren’t in use yet, but they are coming and we need to be prepared.”
In the study, Knightly, Brown University engineering Professor Daniel Mittleman and colleagues showed an attacker could easily make a sheet of office paper covered with 2D foil symbols — a metasurface — and use it to redirect part of a 150 gigahertz “pencil beam” transmission between two users.
They dubbed the attack “Metasurface-in-the-Middle” as a nod to both the hacker’s tool and the way it is wielded. Metasurfaces are thin sheets of material with patterned designs that manipulate light or electromagnetic waves. “Man-in-the-middle” is a computer security industry classification for attacks in which an adversary secretly inserts themself between two parties.
The 150 gigahertz frequency is higher than is used in today’s 5G cellular or Wi-Fi networks. But Knightly said wireless carriers are looking to roll out 150 gigahertz and similar frequencies known as terahertz waves or millimeter waves over the next decade. More

A wireless, bioelectronic pacifier could eliminate the need for invasive, twice-daily blood draws to monitor babies’ electrolytes in Newborn Intensive Care Units or NICUs.
This smart pacifier can also provide more continuous monitoring of sodium and potassium ion levels. These electrolytes help alert caregivers if babies are dehydrated, a danger for infants, especially those born prematurely or with other health issues.
Researchers tested the smart pacifier on a selection of infants in a hospital, and the results were comparable to data gained from their normal blood draws. They detailed their findings in a proof-of-concept study published in the journal Biosensors and Bioelectronics.
“We know that premature babies have a better chance of survival if they get a high quality of care in the first month of birth,” said Jong-Hoon Kim, associate professor at the Washington State University School of Engineering and Computer Science and a co-corresponding author on the study. “Normally, in a hospital environment, they draw blood from the baby twice a day, so they just get two data points. This device is a non-invasive way to provide real-time monitoring of the electrolyte concentration of babies.”
The blood-draw method can be potentially painful for the infant, and it leaves big gaps in information since they are usually done once in the morning and once in the evening, Kim pointed out. Other methods have been developed to test an infants’ saliva for these electrolytes, but they involve bulky, rigid devices that require a separate sample collection.
Using a common, commercially available pacifier, the researchers created a system that samples a baby’s saliva through microfluidic channels. Whenever the baby has the pacifier in their mouth, saliva is naturally attracted to these channels, so the device doesn’t require any kind of pumping system.
The channels have small sensors inside that measure the sodium and potassium ion concentrations in the saliva. Then this data is relayed wirelessly using Bluetooth to the caregiver.
For the next step of development, the research team plans to make the components more affordable and recyclable. Then, they will work to set up a larger test of the smart pacifier to establish its efficacy.
Kim said development of this device is part of a broader effort to help make NICU treatment less disruptive for their tiny patients.
“You often see NICU pictures where babies are hooked up to a bunch of wires to check their health conditions such as their heart rate, the respiratory rate, body temperature, and blood pressure,” said Kim. “We want to get rid of those wires.”
Along with Kim, co-authors on this study include researchers from Georgia Institute of Technology, Pukyong National University and Yonsei University College of Medicine in South Korea as well as WSU.
Story Source:
Materials provided by Washington State University. Original written by Sara Zaske. Note: Content may be edited for style and length. More

Robot-assisted surgery used to perform bladder cancer removal and reconstruction enables patients to recover far more quickly and spend significantly (20 per cent) less time in hospital, concludes a first-of-its kind clinical trial led by scientists at UCL and the University of Sheffield.
The study, published in JAMA and funded by The Urology Foundation with a grant from the Champniss Foundation, also found robotic surgery reduced the chance of readmission by half (52 per cent), and revealed a “striking” four-fold (77 per cent) reduction in prevalence of blood clots (deep vein thrombus & pulmonary emboli) — a significant cause of health decline and morbidity — when compared to patients who had open surgery.
Patients’ physical activity — assessed by daily steps tracked on a wearable smart sensor — stamina and quality of life also increased.
Unlike open surgery, where a surgeon works directly on a patient and involves large incisions in the skin and muscle, robot-assisted surgery allows surgeons to guide minimally invasive instruments remotely using a console and aided by 3D view. It is currently only available in a small number of UK hospitals.
Researchers say the findings provide the strongest evidence so far of the patient benefit of robot-assisted surgery and are now urging National Institute of Clinical Excellence (NICE) to make it available as a clinical option across the UK for all major abdominal surgeries including colorectal, gastro-intestinal, and gynaecological.
Co-Chief Investigator, Professor John Kelly, Professor of Uro-Oncology at UCL’s Division of Surgery & Interventional Science and consultant surgeon at University College London Hospitals, said: “Despite robot-assisted surgery becoming more widely available, there has been no significant clinical evaluation of its overall benefit to patients’ recovery. More