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Simple Blood Test To Detect Eight Types Of Cancer

Johns Hopkins Kimmel Cancer Center researchers developed a single blood test that screens for eight common cancer types and helps identify the location of the cancer.

The test, called CancerSEEK, is a unique noninvasive, multianalyte test that simultaneously evaluates levels of eight cancer proteins and the presence of cancer gene mutations from circulating DNA in the blood. The test is aimed at screening for eight common cancer types that account for more than 60 percent of cancer deaths in the U.S. Five of the cancers covered by the test currently have no screening test.


The use of a combination of selected biomarkers for early detection has the potential to change the way we screen for cancer, and it is based on the same rationale for using combinations of drugs to treat cancers,” says Nickolas Papadopoulos, Ph.D., senior author and professor of oncology and pathology.

Circulating tumor DNA mutations can be highly specific markers for cancer. To capitalize on this inherent specificity, we sought to develop a small yet robust panel that could detect at least one mutation in the vast majority of cancers,” adds Joshua Cohen, an M.D.-Ph.D. student at the Johns Hopkins University School of Medicine and the paper’s first author. “In fact, keeping the mutation panel small is essential to minimize false-positive results and keep such screening tests affordable.”

The findings were published online by Science.


How To Detect Alzheimer’s 30 years In Advance

Scientists from Japan and Australia have teamed up to develop and validate a blood test for Alzheimer’s disease, with the potential to massively ramp up the pace of Alzheimer’s disease drug trials. The blood test measures a specific peptide in the blood to inform scientists, with 90 per cent accuracy, if a patient has the very earliest stages of Alzheimer’s diseaseBlood samples from patients in a large study from the Japanese National Center for Geriatrics and Gerontology (NCGG) were initially analysed to identify the relevant peptides. Those indicating brain beta-amyloid burden were then tested against patient samples from the Australian Imaging, Biomarker and Lifestyle Study of Aging (AIBL), to validate the results.


Our study demonstrates the high accuracy, reliability and reproducibility of this blood test, as it was successfully validated in two independent large datasets from Japan and Australia.” says Professor Katsuhiko Yanagisawa, Director-general of Research Institute at NCGG.

Dr Koichi Tanaka at Shimadzu Corporation was instrumental in developing the initial blood testing procedure. Professor Tanaka won the Nobel prize in Chemistry in 2002 for the technique. “From a tiny blood sample, our method can measure several amyloid-related proteins, even though their concentration is extremely low. We found that the ratio of these proteins was an accurate surrogate for brain amyloid burden.”

One of the essential hallmarks of Alzheimer’s disease is buildup of abnormal peptide in the brain, called beta-amyloid. The process starts silently about 30 years before outward signs of dementia, like memory loss or cognitive decline, have begun.

Current tests for beta-amyloid include brain scans with costly radioactive tracers, or analysing spinal fluid taken via a lumbar puncture. These are expensive and invasive, and generally only available in a research setting. A diagnosis is usually made without these tools, by assessing a patient’s range of symptoms.

Laureate Professor Colin Masters of the Florey Institute of Neuroscience and Mental Health, and The University of Melbourne, has been at the forefront of Alzheimer’s research since the 1980s. Professor Masters, who co-led the research published in the latest issue of Nature, comments: “This new test has the potential to eventually disrupt the expensive and invasive scanning and spinal fluid technologies. In the first instance, however, it will be an invaluable tool in increasing the speed of screening potential patients for new drug trials.


TriboElectricity, The Green Energy Source

Researchers from Clemson’s Nanomaterials Institute (CNI) are one step closer to wirelessly powering the world using triboelectricity, a green energy source. In March 2017, a group of physicists at CNI invented the ultra-simple triboelectric nanogenerator or U-TENG, a small device made of plastic and tape that generates electricity from motion and vibrations. When the two materials are brought together — through such actions as clapping the hands or tapping feet — they generate voltage that is detected by a wired, external circuit. Electrical energy, by way of the circuit, is then stored in a capacitor or a battery until it’s needed.

Nine months later, in a paper published in the journal Advanced Energy Materials, the researchers reported that they had created a wireless TENG, called the W-TENG, which greatly expands the applications of the technology. The W-TENG was engineered under the same premise as the U-TENG using materials that are so opposite in their affinity for electrons that they generate a voltage when brought in contact with each other.

In the W-TENG, plastic was swapped for a multipart fiber made of graphene — a single layer of graphite, or pencil lead — and a biodegradable polymer known as polylactic acid (PLA). PLA on its own is great for separating positive and negative charges, but not so great at conducting electricity, which is why the researchers paired it with graphene. Kapton tape, the electron-grabbing material of the U-TENG, was replaced with Teflon, a compound known for coating nonstick cooking pans.

After assembling the graphene-PLA fiber, the researchers pulled it into a 3-D printer and the W-TENG was born. The end result is a device that generates a maximum of 3,000 volts — enough to power 25 standard electrical outlets or, on a grander scale, smart-tinted windows or a liquid crystal display (LCD) monitor. Because the voltage is so high, the W-TENG generates an electric field around itself that can be sensed wirelessly. Its electrical energy, too, can be stored wirelessly in capacitors and batteries.

It cannot only give you energy, but you can use the electric field also as an actuated remote. For example, you can tap the W-TENG and use its electric field as a ‘button’ to open your garage door, or you could activate a security system — all without a battery, passively and wirelessly,” said Sai Sunil Mallineni, the first author of the study and a Ph.D. student in physics and astronomy.


Flexible, Low-Cost, Water-Repellent Gaphene Circuits

New graphene printing technology can produce electronic circuits that are low-cost, flexible, highly conductive and water repellent. The nanotechnology “would lend enormous value to self-cleaning wearable/washable electronics that are resistant to stains, or ice and biofilm formation,” according to a recent paper describing the discovery.

“We’re taking low-cost, inkjet-printed graphene and tuning it with a laser to make functional materials,” said Jonathan Claussen, an Iowa State University assistant professor of mechanical engineering, an associate of the U.S. Department of Energy’s and the corresponding author of the paper recently featured on the cover of the journal Nanoscale. The paper describes how Claussen and the nanoengineers in his research group use to create electric circuits on flexible materials. In this case, the ink is flakes of graphene – the wonder material can be a great conductor of electricity and heat, plus it’s strong, stable and biocompatible.

And now they’ve found another application of their laser processing technology: taking graphene-printed circuits that can hold water droplets (they’re hydrophilic) and turning them into circuits that repel water (they’re superhydrophobic).

We’re micro-patterning the surface of the inkjet-printed graphene,” Claussen said. “The laser aligns the graphene flakes vertically – like little pyramids stacking up. And that’s what induces the hydrophobicity.” Claussen said the energy density of the laser processing can be adjusted to tune the degree of hydrophobicity and conductivity of the printed graphene circuits. And that opens up all kinds of possibilities for new electronics and sensors, according to the paper. “One of the things we’d be interested in developing is anti-biofouling materials,” said Loreen Stromberg, a paper co-author and an Iowa State postdoctoral research associate in mechanical engineering and for the Virtual Reality Applications Center. “This could eliminate the buildup of biological materials on the surface that would inhibit the optimal performance of devices such as chemical or biological sensors.”

The technology could also have applications in flexible electronics, washable sensors in textiles, microfluidic technologies, drag reduction, de-icing, electrochemical sensors and technology that uses graphene structures and electrical simulation to produce stem cells for nerve regeneration. The researchers wrote that further studies should be done to better understand how the nano– and microsurfaces of the printed graphene creates the water-repelling capabilities. .

The Iowa State University Research Foundation is working to patent the technology and has optioned it to an Ames-based startup, NanoSpy Inc., for possible commercialization. NanoSpy, located at the Iowa State University Research Park, is developing sensors to detect salmonella and other pathogens in food processing plants. Claussen and Stromberg are part of the company.


AI Improves Heart Disease Diagnosis

Researchers from the University of Oxford are using artificial intelligence (AI) to improve diagnostic accuracy for heart disease. The team hope to roll out the system across the NHS later this year, helping to improve patient outcomes and saving millions is misdiagnoses. The research, led by Prof Paul Leeson and RDM DPhil student Ross Upton (Cardiovascular Clinical Research Facility), took place in the Oxford University Hospitals Foundation Trust and is the basis of spin-out company Ultromics.


Thousands of people every year have an echocardiogram – a type of heart scan – after visiting hospital suffering with chest pain. Clinicians currently assess these scans by eye, taking into account many features that could indicate whether someone has heart disease and if they are likely to go on to have a heart attack. But even the most well trained cardiologist can misdiagnose patients. Currently, 1 in 5 scans are misdiagnosed each year – the equivalent to 12,000 patients. This means that people are either not being treated to prevent a heart attack, or they are undergoing unnecessary operations to stave off a heart attack they won’t have.

The new system uses machine learning – a form of artificial intelligence – to tap into the rich information provided in an echocardiogram. Using the new system, AI can detect 80,000 subtle changes inviable to the naked eye, improving the accuracy of diagnosis to 90%. The machine learning system was trained using scans from previous patients, alongside data about whether they went on to have a heart attack. The team hope that the improved diagnostic accuracy will not only improve patient care and outcomes, but save the NHS £300million a year in avoidable operations and treatment.  So far the system has been trialled in six cardiology units in the UK. Further implementation of the technology is now being led by Ultromics – a spin-out company co-founded by Ross Upton and Paul Leeson (Cardiovascular Clinical Research Facility). The software will be made available for free throughout the NHS later this year.


Memristors Retain Data 10 Years Without Power

The internet of things ( IoT) is coming, that much we know. But still it won’t; not until we have components and chips that can handle the explosion of data that comes with IoT. In 2020, there will already be 50 billion industrial internet sensors in place all around us. A single autonomous device – a smart watch, a cleaning robot, or a driverless car – can produce gigabytes of data each day, whereas an airbus may have over 10 000 sensors in one wing alone.

Two hurdles need to be overcome. First, current transistors in computer chips must be miniaturized to the size of only few nanometres; the problem is they won’t work anymore then. Second, analysing and storing unprecedented amounts of data will require equally huge amounts of energy. Sayani Majumdar, Academy Fellow at Aalto University (Finland), along with her colleagues, is designing technology to tackle both issues.

Majumdar has with her colleagues designed and fabricated the basic building blocks of future components in what are called “neuromorphiccomputers inspired by the human brain. It’s a field of research on which the largest ICT companies in the world and also the EU are investing heavily. Still, no one has yet come up with a nano-scale hardware architecture that could be scaled to industrial manufacture and use.

The probe-station device (the full instrument, left, and a closer view of the device connection, right) which measures the electrical responses of the basic components for computers mimicking the human brain. The tunnel junctions are on a thin film on the substrate plate.

The technology and design of neuromorphic computing is advancing more rapidly than its rival revolution, quantum computing. There is already wide speculation both in academia and company R&D about ways to inscribe heavy computing capabilities in the hardware of smart phones, tablets and laptops. The key is to achieve the extreme energy-efficiency of a biological brain and mimic the way neural networks process information through electric impulses,” explains Majumdar.

In their recent article in Advanced Functional Materials, Majumdar and her team show how they have fabricated a new breed of “ferroelectric tunnel junctions”, that is, few-nanometre-thick ferroelectric thin films sandwiched between two electrodes. They have abilities beyond existing technologies and bode well for energy-efficient and stable neuromorphic computing.

The junctions work in low voltages of less than five volts and with a variety of electrode materials – including silicon used in chips in most of our electronics. They also can retain data for more than 10 years without power and be manufactured in normal conditions.

Tunnel junctions have up to this point mostly been made of metal oxides and require 700 degree Celsius temperatures and high vacuums to manufacture. Ferroelectric materials also contain lead which makes them – and all our computers – a serious environmental hazard.

Our junctions are made out of organic hydro-carbon materials and they would reduce the amount of toxic heavy metal waste in electronics. We can also make thousands of junctions a day in room temperature without them suffering from the water or oxygen in the air”, explains Majumdar.

What makes ferroelectric thin film components great for neuromorphic computers is their ability to switch between not only binary states – 0 and 1 – but a large number of intermediate states as well. This allows them to ‘memoriseinformation not unlike the brain: to store it for a long time with minute amounts of energy and to retain the information they have once received – even after being switched off and on again.

We are no longer talking of transistors, but ‘memristors’. They are ideal for computation similar to that in biological brains.  Take for example the Mars 2020 Rover about to go chart the composition of another planet. For the Rover to work and process data on its own using only a single solar panel as an energy source, the unsupervised algorithms in it will need to use an artificial brain in the hardware.

What we are striving for now, is to integrate millions of our tunnel junction memristors into a network on a one square centimetre area. We can expect to pack so many in such a small space because we have now achieved a record-high difference in the current between on and off-states in the junctions and that provides functional stability. The memristors could then perform complex tasks like image and pattern recognition and make decisions autonomously,” says Majumdar.


Flat Lens Boost Virtual Reality

Metalensesflat surfaces that use nanostructures to focus light — promise to revolutionize optics by replacing the bulky, curved lenses currently used in optical devices with a simple, flat surface.  But, these metalenses have remained limited in the spectrum of light they can focus well Now a team of researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) has developed the first single lens that can focus the entire visible spectrum of light — including white light — in the same spot and in high resolution. This has only ever been achieved in conventional lenses by stacking multiple lenses.

Focusing the entire visible spectrum and white light – combination of all the colors of the spectrum — is so challenging because each wavelength moves through materials at different speeds. Red wavelengths, for example, will move through glass faster than the blue, so the two colors will reach the same location at different times resulting in different foci. This creates image distortions known as chromatic aberrations.

Cameras and optical instruments use multiple curved lenses of different thicknesses and materials to correct these aberrations, which, of course, adds to the bulk of the device.

Metalenses have advantages over traditional lenses,” says Federico Capasso, Professor of Applied Physics at SEAS and senior author of the research. “Metalenses are thin, easy to fabricate and cost effective. This breakthrough extends those advantages across the whole visible range of light. This is the next big step. Using our achromatic lens, we are able to perform high quality, white light imaging. This brings us one step closer to the goal of incorporating them into common optical devices such as cameras“.

The research is published in Nature Nanotechnology.


How To Detect Cancer With a Urine Test

Researchers centered at Nagoya University (Japan) develop a nanowire device able to detect microscopic levels of urinary markers potentially implicated in cancerCells communicate with each other through a number of different mechanisms. Some of these mechanisms are well-known: in animals, for example, predatory threats can drive the release of norepinephrine, a hormone that travels through the bloodstream and triggers heart and muscle cells to initiate a “fight-or-flight” response. A far less familiar mode of cellular transport is the extracellular vesicle (EV). EVs can be thought of as small “chunks” of a cell that are able to pinch off and circulate throughout the body to deliver messenger cargo to other cells. These messengers have become increasingly recognized as crucial mediators of cell-to-cell communication.

In a new study reported in Science Advances, researchers centered at Nagoya University have developed a novel medical device that can efficiently capture these EVs, and potentially use them to screen for cancer.


EVs are potentially useful as clinical markers. The composition of the molecules contained in an EV may provide a diagnostic signature for certain diseases,” lead author Takao Yasui explains. “The ongoing challenge for physicians in any field is to find a non-invasive diagnostic tool that allows them to monitor their patients on a regular basis–for example, a simple urine test.”

Among the many molecules EVs have been found to harbor are microRNAs, which are short pieces of ribonucleic acid that play diverse roles in normal cellular biology. Critically, the presence of certain microRNAs in urine might serve as a red flag for serious conditions such as bladder and prostate cancer. While this important cargo could therefore theoretically aid physicians in cancer diagnoses, there are still many technological hurdles that need to be overcome. One such hurdle: finding a feasible method to capture EVs in sufficient quantities to analyze them in a routine clinical setting.

The content of EVs in urine is extremely low, at less than 0.01% of the total fluid volume. This is a major barrier to their diagnostic utility,” Yasui notes. “Our solution was to embed zinc oxide nanowires into a specialized polymer to create a material that we believed would be highly efficient at capturing these vesicles. Our findings suggest that the device is indeed quite efficient. We obtained a collection rate of over 99%, surpassing ultracentrifugation as well as other methods that are currently being used in the field.


Nano-based Air Purifier Destroys Pollutants

Molekule, a San Francisco-based startup with a sleekly designed molecular air purifier started as an immigrant dream twenty years ago and ended up being named one of Time’s top 25 inventions of 2017. The inventor Yogi Goswami came up with the idea when his baby son Dilip started having a hard time breathing the air around him. Dilip suffered from severe asthma but no air purifier at the time seemed to work well enough to clean up indoor pollutants. Traditional HEPA filters simply trap a few pollutants but they don’t grab everything and they don’t break them down before releasing them back into the air.

So, Goswami the elder came up with a filter technology that could both suck up things like allergens, mold and bacteria and particles up to one-thousand times smaller than what a HEPA filter can catch using photo electrochemical oxidation (PECO) and nanotechnology to destroy the pollutants on a molecular level and eliminate the full spectrum of indoor air pollutants. The result? Clean, breathable air that even the most sensitive person can handle. Dilip and his sister Jaya Goswami patented the tech and founded Molekule to bring their father’s invention to the rest of us.

The company now ships a stylish $800, two-foot-tall cylinder with the patented filter inside. Sure, it’s a lot pricier than most filters out there but the company also offers financing at $67 a month. It was also instrumental in helping folks breathe during the Northern California wildfires this fall. Jaya mentioned Molekule’s inventory was completely depleted during that time and that the company couldn’t ship fast enough — the product is still backordered till January 3rd, 2018. So far Molekule has brought in just over $13 million in venture funding to keep it going.


How To Store Solar Energy In A Non-Electric Battery

Materials chemists have been trying for years to make a new type of battery that can store solar or other light-sourced energy in chemical bonds rather than electrons, one that will release the energy on demand as heat instead of electricity–addressing the need for long-term, stable, efficient storage of solar power.

Now a group of materials chemists at the University of Massachusetts Amherst led by Dhandapani Venkataraman, with Ph.D. student and first author Seung Pyo Jeong, Ph.D. students Larry Renna, Connor Boyle and others, report that they have solved one of the major hurdles in the field by developing a polymer-based system. It can yield energy storage density – the amount of energy stored – more than two times higher than previous polymer systems. Details appear in the current issue of Scientific Reports.

Venkataraman and Boyle say that previous high energy storage density achieved in a polymeric system was in the range of 200 Joules per gram, while their new system is able to reach an average of 510 Joules per gram, with a maximum of 690. Venkataraman says, “Theory says that we should be able to achieve 800 Joules per gram, but nobody could do it. This paper reports that we’ve reached one of the highest energy densities stored per gram in a polymeric system, and how we did it.”


Thermoelectric Power Generation

Thermoelectric (TE) materials could play a key role in future technologies. Although the applications of these remarkable compounds have long been explored, they are mostly limited to high-temperature devices. Recently, researchers at Osaka University, in collaboration with Hitachi, Ltd., developed a new TE material with an improved power factor at room temperature. Their study, published in Physica Status Solidi RRL, could help bring these materials out of the high-temperature niche and into the mainstream.

TE materials display the thermoelectric effect: apply heat on one side, and an electric current starts to flow. Conversely, run an external current through the device, and a  temperature gradient forms; i.e., one side becomes hotter than the other. By interconverting heat and electricity, TE materials can be used as either power generators (given a heat source) or refrigerators (given a power supply).

The ideal TE material combines high electrical conductivity, allowing the current to flow, with low thermal conductivity, which prevents the temperature gradient from evening out. The power generation performance mainly depends on the “power factor,” which is proportional to both electrical conductivity and a term called the Seebeck coefficient.

Unfortunately, most TE materials are often based on rare or toxic elements,” according to study co-author Sora-at Tanusilp. “To address this, we combined silicon – which is common in TE materials – with ytterbium, to create ytterbium silicide [YbSi2]. We chose ytterbium over other metals for several reasons. First, its compounds are good electrical conductors. Second, YbSi2 is non-toxic. Moreover, this compound has a specific property called valence fluctuation that make it a good TE material at low temperatures.


The Smell Of Death

Scientists in Korea have developed a bioelectronicnose’ that can specifically detect a key compound produced in decaying substances. When food begins to rot, the smell that we find repulsive comes from a compound known as cadaverine. That is also the substance responsible for the stench of rotting bodies, or cadavers—hence the name. The compound is the result of a bacterial reaction involving lysine, which is an amino acid commonly found in various food products. A previous study has shown that a receptor in zebrafish has an affinity for cadaverine. To make this receptor in the laboratory, scientists have turned to Escherichia coli bacteria as a host cell because it can easily produce large quantities of proteins. However, the production of this receptor in E. coli has been a challenge because it needs to be embedded in a membrane.

In this study, a team of researchers led by Associate Professor Hong Seunghun at Seoul National University packaged the cadaverine receptor from the zebrafish into nanodiscs, which are water friendly, membrane-like structures. The researchers then placed the receptor-containing nanodiscs in a special orientation on a carbon nanotube transistor, completing the bioelectronic nose. During testing with purified test compounds and real-world salmon and beef samples, the nose was selective and sensitive for cadaverine, even at low levels. The researchers suggest that the detector could someday prove useful in natural disaster scenarios, to recover corpses for identification.

The findings have been published in the journal ACS Nano.