“There’s nothing available on the market that covers this range of X-rays,” Mandal said. “Nobody has explored this region, and there will be many innovations that will result from our being able to do so, particularly when it comes to medical imaging.”
X-rays are part of the electromagnetic spectrum, which ranges from low-energy radio waves to high-energy gamma rays. X-rays are on the high-energy end of the spectrum, just below gamma rays – they’re more energetic than ultraviolet light, which is more energetic than visible light.
As they just reported in Applied Physics Letters, the USC engineers have developed a laboratory-scale device that sensitively detects what are called “soft X-rays” – those on the lowest end of the X-ray energy scale.
At the other end of the X-ray spectrum are hard X-rays. The typical “X-ray” taken at a doctor’s or dentist’s office is a black-and-white photograph showing where hard X-rays were able to penetrate (the black area) or unable to penetrate (the white area) the object between the X-ray source and detector.
“If you take mammography as an example, hard X-rays pose difficulties,” Mandal said. “First, they have very high energy, and so we have to minimize exposure to them.” Soft X-ray devices are potentially less harmful to patients than those based on hard X-rays, he said.
“And more importantly, the soft X-rays interact with calcifications in the tissue,” he added. “Hard X-rays do not – they just pass through calcium deposits.”
Calcification is the deposition of calcium minerals in body tissue; in the breast it can be an indicator of pathology. Not as opaque as bone to X-rays, calcium deposits represent an very promising target for detailed soft X-ray mapping, Mandal said. He envisions the new soft X-ray detectors being at the forefront of a new way of imaging breast tissue, so that physicians can follow progression of calcification over time.
“It’s common for women even under 40 years of age to have calcifications,” Mandal said. “It’s critical to know whether it exists in the tissue and especially whether it is spreading.”
“But to see that, we need very high resolution detection systems, which is what we’ve made. These detectors are instantaneous, real-time and will be able to operate at room temperature with high resolution.”
Mandal’s team constructed the detector through epitaxial growth of silicon carbide on wafers of 4H-SiC. They were tested for response to soft X-rays at both the Los Alamos National Laboratory and Brookhaven National Laboratory.
The resulting detectors exhibited high sensitivity for soft X-rays (50 to 10,000 electron volts). There are no commercially available soft X-ray detectors covering this range, Mandal said, and comparison with an off-the-shelf ultraviolet detector showed a much more robust response for soft X-rays with the new device.
Steven Powell | Newswise Science News
Can radar replace stethoscopes?
14.08.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg
Novel PET imaging method could track and guide therapy for type 1 diabetes
03.08.2018 | Society of Nuclear Medicine and Molecular Imaging
New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference
Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
17.08.2018 | Event News
08.08.2018 | Event News
27.07.2018 | Event News
17.08.2018 | Physics and Astronomy
17.08.2018 | Information Technology
17.08.2018 | Life Sciences