in present pet/ct scanners, pet attenuation correction is performed by relying on the information given by ct scan. in the ct-based attenuation correction methods, dual-energy technique (dect) is the most accurate approach, which has been limited due to the increasing patient dose. in this feasibility study, we have introduced a new method that can implement dual-energy technique with only a si...

Most potassium-ion battery (PIB) cathode materials have deficient structural stability because of the huge radius potassium ion, leading to inferior cycling performance. We report controllable synthesis a novel low-strain phosphate material K3(VO)(HV2O3)(PO4)2(HPO4) (denoted KVP) nanorulers as an efficient for PIBs. The as-synthesized KVP nanoruler exhibits initial reversible capacity 80.6 mAh ...

During the recommissioning of a Philips RT-250 kilovoltage X-ray unit, unexpected output variations with tube head rotation (cross-plane) and tube head tilt (in-plane) were observed. The measured output showed an increase of up to 7.3% relative to the neutral position (0? in-plane and 0? cross-plane) over the possible range of angles of in-plane rotation for 75 kVp (half-value layer, HVL = 1.84...

PURPOSE To study the effect of different filters on the dose response curves of the Gafchromic XRQA2 film. To measure the kV XVI cone-beam CT (CBCT) surface dose received during 3D and 4D imaging protocols in three body regions (head and neck, chest and pelvis). METHODS GafChromic XR- QA2 film (International Specialty Products, Wayne, NJ) dose response curves were generated for three irradiat...

BACKGROUND This study is to investigate the feasibility of low iodine concentration contrast material (CM) combined with low tube voltage and adaptive statistical iterative reconstruction (ASIR) in renal computed tomography angiography (CTA). MATERIAL AND METHODS A total of 136 patients were enrolled in this prospective trial, and randomly divided into two groups: group A (n=68) and group B (n=...

The optimization of dual-energy computed tomography (DE-CT) is challenged by the lack of a theoretical foundation for image quality. This work reports a cascaded systems analysis model that was used to derive signal and noise propagation in DE-CBCT in prevalent Fourier metrics such as the noise-power spectrum (NPS) and noise-equivalent quanta (NEQ). The model was validated in comparison to meas...

PURPOSE Bombarding high-Z material with x-ray radiation releases Auger electrons and Coster-Kronig electrons, along with deeper penetrating fluorescent x-rays and photoelectrons. The Auger and Coster-Kronig electron penetration distance is on the order of nanometers to micrometers in water or tissue, creating a large dose enhancement accompanied by a RBE greater than 1 at the cellular level. Th...

Ionizing radiation is known for its cytotoxic and mutagenic properties. However, recent evidence suggests that chronic sub-lethal irradiation stimulates the growth of melanin-pigmented (melanized) fungi, supporting the hypothesis that interactions between melanin and ionizing photons generate energy useful for fungal growth, and/or regulate growth-promoting genes. There are no quantitative mode...

BACKGROUND This study was performed to assess whether iterative reconstruction can reduce radiation dose while maintaining acceptable image quality, and to investigate whether perfusion parameters vary from conventional filtered back projection (FBP) at the low-tube-voltage (80-kVp) during whole-pancreas perfusion examination using a 256-slice CT. METHODS 76 patients with known or suspected p...

*Corresponding Author: Dr. Mohammad Bagher Tavakoli, Department of Medical Physics and Medical Engineering, Isfahan University of Medical Sciences, Isfahan, Iran. Fax: +98 311 7922412 E-mail: [email protected] Background: Breast is one of the main radiological sensitive organs, hence it is important to evaluate absorbed dose to this organ especially to the glandular parts. It is the aim of t...