Improving diagnostic precision in amyloid brain PET imaging through data-driven motion correction.

Background: Head motion during brain positron emission tomography (PET)/computed tomography (CT) imaging degrades image quality, resulting in reduced reading accuracy. We evaluated the performance of a head motion correction algorithm using F-flutemetamol (FMM) brain PET/CT images.

Methods: FMM brain PET/CT images were retrospectively included, and PET images were reconstructed using a motion correction algorithm: (1) motion estimation through 3D time-domain signal analysis, signal smoothing, and calculation of motion-free intervals using a Merging Adjacent Clustering method; (2) estimation of 3D motion transformations using the Summing Tree Structural algorithm; and (3) calculation of the final motion-corrected images using the 3D motion transformations during the iterative reconstruction process.

Spectrally Selective Inorganic-Based Multilayer Emitter for Daytime Radiative Cooling.

Daytime radiative coolers are used to pump excess heat from a target object into a cold exterior space without energy consumption. Radiative coolers have become attractive cooling options. In this study, a daytime radiative cooler was designed to have a selective emissive property of electromagnetic waves in the atmospheric transparency window of 8-13 μm and preserve low solar absorption for enhancing radiative cooling performance.

Programmable Fabrication of Submicrometer Bent Pillar Structures Enabled by a Photoreconfigurable Azopolymer.

Anisotropic small structures found throughout living nature have unique functionalities as seen by Gecko lizards. Here, we present a simple yet programmable method for fabricating anisotropic, submicrometer-sized bent pillar structures using photoreconfiguration of an azopolymer. A slant irradiation of a p-polarized light on the pillar structure of an azopolymer simply results in a bent pillar structure.

Does nonexistent of your hands on the screen guarantee no radiation exposure to your body? - Study on exposure of the practitioner's hands to radiation during C-arm fluoroscopy-guided injections and effectiveness of a new shielding device.

Observational phantom study.This study aimed to evaluate the radiation exposure dose of practitioner's hands when performing C-arm guided procedures and to determine the usefulness of our newly designed radiation shielding device.C-arm guided procedures including lumbar transforaminal epidural steroid injections (TFESIs) are commonly used for pain control induced by lumbar radiculopathy.

Design of a Broadband Solar Thermal Absorber Using a Deep Neural Network and Experimental Demonstration of Its Performance.

In using nanostructures to design solar thermal absorbers, computational methods, such as rigorous coupled-wave analysis and the finite-difference time-domain method, are often employed to simulate light-structure interactions in the solar spectrum. However, those methods require heavy computational resources and CPU time. In this study, using a state-of-the-art modeling technique, i.

Effective Radiative Properties of Tilted Metallic Nanorod Arrays Considering Polarization Coupling.

With the advent of new nanomanufacturing techniques has come the rise of the field of nanophotonics and an increased need to determine optical properties of novel structures. Commercial software packages are able to estimate the behavior, but require large resources and heavy computational time. By combining coordinate transforms and Effective Medium Theory (EMT), an effective relative permittivity tensor is defined and further exploited to calculate the polarization-coupled Fresnel coefficients through Maxwell's equations.

Development of a fiber-optic gamma endoscope to measure both optical and gamma images in a confined space.

In nuclear medicine, obtaining information on the exact location, size, and dose of radiopharmaceuticals distributed on lesions is critically important. Therefore, we have fabricated a novel fiber-optic gamma endoscope (FOGE) to measure the shape and size of the radioisotope as well as the gamma-ray distribution simultaneously. To evaluate the performance of the novel FOGE, we obtained optical images and gamma images by using a USAF 1951 target and radioisotope sources, respectively.

Performance Evaluation of a Multichannel All-In-One Phantom Dosimeter for Dose Measurement of Diagnostic X-ray Beam.

We developed a multichannel all-in-one phantom dosimeter system composed of nine sensing probes, a chest phantom, an image intensifier, and a complementary metal-oxide semiconductor (CMOS) image sensor to measure the dose distribution of an X-ray beam used in radiation diagnosis. Nine sensing probes of the phantom dosimeter were fabricated identically by connecting a plastic scintillating fiber (PSF) to a plastic optical fiber (POF). To measure the planar dose distribution on a chest phantom according to exposure parameters used in clinical practice, we divided the top of the chest phantom into nine equal parts virtually and then installed the nine sensing probes at each center of the nine equal parts on the top of the chest phantom as measuring points.