Purpose: Compressed sensing theory has enabled an accurate, low-dose cone-beam computed tomography (CBCT) reconstruction using a minimal number of noisy projections. However, the time remains significant challenge for practical implementation in clinic. In this work, we propose novel gradient projection algorithm, based on Gradient-Projection-Barzilai-Borwein formulation (GP-BB), that handles total variation (TV)-norm regularization-based least squares problem CBCT highly efficient manner,...

A dedicated small-animal x-ray micro computed tomography (micro-CT) system has been developed to screen laboratory small animals such as mice and rats. The micro-CT consists of an indirect-detection flat-panel detector with a field-of-view 120 × mm2, microfocus source, rotational subject holder parallel data processing system. is based on matrix-addressed photodiode array fabricated by CMOS (complementary metal-oxide semiconductor) process coupled CsI:Tl (thallium-doped caesium iodide)...

As a part of our ongoing search for bioactive constituents from natural Korean sources, the investigation rhizomes Acorus gramineus afforded five new lignans, named ligraminols A–E (1–5), together with seven known ones (6–12). The structures 1–5 were determined by combination 1D and 2D NMR, HRMS, CD, enzymatic hydrolysis. Compounds 1–12 tested their antiproliferative activities toward panel human-derived normal cancer cell lines. Moreover, compounds evaluated inhibitory on nitric oxide...

Single-photon-counting (SPC) x-ray imaging has the potential to improve image quality and enable novel energy-dependent methods. Similar conventional detectors, optimizing SPC will require systems that produce highest possible detective quantum efficiency (DQE). This paper builds on cascaded-systems analysis (CSA) framework develop a comprehensive description of DQE detectors implement adaptive binning. The can be described using CSA approach by propagating probability density function (PDF)...

The prevalent use of unsustainable polymers in current X‐ray scintillators poses a significant environmental concern. advancement biodegradable holds promise mitigating escalating issues tied to electronic or medical waste and carbon footprints. Herein, flexible scintillation film is presented employing lead‐free 0D Cs 3 Cu 2 I 5 perovskite nanoparticles integrated into densified‐delignified wood (Cs @D‐Wood). @D‐Wood demonstrates precise detailed imaging capabilities, achieving high spatial...

Purpose: Energy‐resolved x‐ray imaging has the potential to improve contrast‐to‐noise ratio by measuring energy of each interacting photon and applying optimal weighting factors. The success energy‐resolving photon‐counting (EPC) detectors relies on ability an detector accurately measure photon. However, escape characteristic emissions Compton scatter degrades spectral information. This article makes theoretical connection between accuracy imprecision in measurements with Swank factor for ,...

Abstract Two new aryl‐tetralin lignan glycosides, linderanosides A and B ( 1 2 , resp.), a dihydrobenzofuran neolignan glycoside, linderanoside C 3 ), together with five known derivatives 4 – 8 ) were isolated from the trunk of Lindera glauca. The structures these compounds determined through spectroscopic analyses, including extensive 2D‐NMR data acid hydrolysis. absolute configurations clarified by circular dichroism (CD) studies. Compounds evaluated for their cytotoxicity against A549...

For Gd <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O S:Tb granular phosphor screens having a wide range of mass thicknesses, we have investigated the fundamental imaging performance in terms modulation-transfer function (MTF), noise-power spectrum (NPS) and detective quantum efficiency (DQE). As an optical photon readout device, CMOS photodiode array with pitch 48 mum was used. Under representative radiation quality, RQA 5,...

Abstract Photon-counting detectors (PCDs) are an attractive technology; they provide multiple- or dual-energy (DE) images after a single X-ray exposure. We evaluated the fundamental imaging performance of CdTe-based DE PCD embedded with optional anticoincidence (AC) function that aggregates signals spread over neighboring pixels and casts this sum to pixel represents highest signal. Furthermore, we compared conventional flat-panel (FPDs) using same spectrum (70 kV 21-mm aluminum filtration)....

Purpose: This study investigates the fundamental signal and noise performance limitations imposed by stochastic nature of x‐ray interactions in selected photoconductor materials, such as Si, a ‐Se, CdZnTe, HgI 2 , PbI PbO, TlBr, for spectra typically used mammography. Methods: It is shown how Monte Carlo simulations can be combined with cascaded model to determine absorbed energy distribution each combination spectrum. The quantum efficiency, mean absorption per interaction, Swank factor,...

A bioassay-guided fractionation and chemical investigation of the MeOH extract from twigs Lindera glauca (SIEB. et ZUCC.) BLUME resulted in isolation identification six lignans (1–6) including three new lignan derivatives, named linderuca (1), B (2), C (3). The structures compounds (1–3) were determined on basis spectroscopic analyses, two dimensional NMR circular dichroism (CD) spectroscopy studies. cytotoxic activities isolates evaluated by determining their inhibitory effects human tumor...

Purpose: Single‐photon counting (SPC) x‐ray imaging has the potential to improve image quality and enable new advanced energy‐dependent methods. The purpose of this study is extend cascaded‐systems analyses (CSA) description detective quantum efficiency (DQE) SPC systems. Methods: Point‐process theory used develop a method propagating mean signal Wiener noise‐power spectrum through thresholding stage (required identify interaction events). transfer relationships are describe zero‐frequency...

We have applied a flat-panel detector to an X-ray cone-beam micro computed tomography (micro-CT) for small-animal imaging. The consists of active matrix transistors and photodiodes with pixel pitch 50 /spl mu/m thallium-doped cesium iodide (CsI:Tl) scintillator as X-ray-to-light conversion layer. was fabricated complementary metal-oxide-semiconductor (CMOS) technology capable submicrometer design line width, hence, it has fill-factor high sim/80%. In addition, the very fast response...

The purpose of this work is to demonstrate an ultra-fast reconstruction technique for digital tomosynthesis (DTS) imaging based on the algorithm proposed by Feldkamp, Davis, and Kress (FDK) using standard general-purpose graphics processing unit (GPGPU) programming interface. To end, FDK-based DTS was programmed “in-house” with C language utilization 1) GPU 2) central (CPU) cards. card consisted 480 cores (2 × 240 dual chip) 1,242 MHz clock speed 1,792 MB memory space. In terms CPU hardware,...

Purpose: X-ray digital subtraction angiography (DSA) is widely used for vascular imaging. However, the need to subtract a mask image can result in motion artifacts and compromised quality. The current interest energy-resolving photon-counting (EPC) detectors offers promise of eliminating other advanced applications using single exposure. authors describe method assessing iodine signal-to-noise ratio (SNR) that may be achieved with energy-resolved (ERA) enable direct comparison approaches...

Purpose: Theoretical models of the detective quantum efficiency (DQE) x‐ray detectors are an important step in new detector development by providing understanding performance limitations and benchmarks. Previous cascaded‐systems analysis (CSA) accounted for photoelectric interactions only. This paper describes extension CSA approach to incorporate coherent incoherent interactions, low‐Z such as silicon selenium. Methods: A parallel‐cascade is used describe three types interactions. The...

Polycrystalline cadmium telluride (CdTe) X-ray photodetector with advanced performance was fabricated in a Schottky diode form by direct thermal deposition (evaporation) on pixelized complementary metal oxide semiconductor (CMOS) readout panel. Our CdTe detector shows such variety of benefits as relatively low process temperature, cost, operation voltage less than 40 V, and higher sensitivity spatial resolution those commercial a-Se detectors. has cubic Zinc Blende structure maintains p-type...

We have modeled the signal and noise propagation in a pixelated scintillator detector by using cascaded linear-systems transfer theory. The main difference from conventional homogeneous is additional X-ray quantum sampling process at beginning stage of model. expressed as multiplication fill factor both noise. numerical simulation shows that, while detective efficiency (DQE) degrades low spatial-frequency band due to sampling, DQE maintains high values high-frequency band, which band-limited...