Results 61 to 70 of about 6,942,219 (182)

Peculiar Magnetosphere‐Atmosphere Coupling and Its Impacts Over the South American Magnetic Anomaly Region

Journal of Geophysical Research: Space Physics, Volume 131, Issue 8, August 2026.
Abstract The auroral‐like sporadic E‐layer is typically observed at altitudes between 100 and 150 km within the South American Magnetic Anomaly region. However, the occurrence of an unusual layer event detected above this altitude range on 18 July 2017 has raised intriguing questions regarding the physical processes responsible for the substantial ...
Lígia A. Da Silva, Hui Li, Laysa C. A. Resende, Vânia F. Andrioli, Angela M. Santos, Juliano Moro, Paulo R. Jauer, Luis Eduardo Vieira, Lívia R. Alves, José Paulo Marchezi, Jiankui Shi, Jiyao Xu, Paulo P. Batista, Jose V. Bageston, Yajun Zhu, Clezio M. Denardini, Chi Wang, Ezequiel Echer, Guotao Yang, Alexandre A. Pimenta, Joaquim R. Costa, Zhengkuan Liu   +21 more
wiley   +1 more source

Spectral CTA-based quantitative differentiation of infarcted and non-infarcted ASPECTS regions in acute stroke

European Radiology Experimental
Objectives Spectral computed tomography (CT) enables material decomposition and monoenergetic imaging, improving infarct-estimation on non-contrast cerebral CT (NCCT). However, beyond NCCT, infarct estimation is also accessible from CT angiography (CTA).
Schekeb Aludin, Agreen Horr, Patrick Langguth, Tristan Klintz, Svea Seehafer, Alexander Gless, Karim Mostafa, Olav Jansen, Naomi Larsen, Lars-Patrick Schmill   +9 more
doaj   +1 more source

Potential of quantitative X‐ray imaging from photon‐counting CT: A novel analysis based on effective atomic number and physical density

Journal of Applied Clinical Medical Physics, Volume 27, Issue 7, July 2026.
Abstract Background Conventional CT assessment of lung lesions is based mainly on morphological features. CT values represent relative X‐ray attenuation that does not directly reflect tissue composition and/or physical density. Quantitative imaging using photon‐counting CT (PC‐CT) has the potential to provide quantitative parameters, such as effective ...
Takashi Asahara, Rina Nishigami, Natsumi Kimoto, Mana Mitani, Yusuke Morimitsu, Noriaki Akagi, Fumiyo Higaki, Toshihiro Iguchi, Takao Hiraki, Hiroaki Hayashi   +9 more
wiley   +1 more source

Computation of the effective atomic number and mass density from virtual monoenergetic photon-counting CT reconstructions

Heliyon
The aim of this work was to develop and test an image-domain-based method for calculating mass density (ρ) and effective atomic number (Zeff) maps from virtual monoenergetic reconstructions generated with the clinically approved photon-counting computed ...
Sebastian Horstmeier, Felix Sebastian Thomsen, Jan Borggrefe   +2 more
doaj   +1 more source

Introduction to TREx‐ATM V2.0: A Versatile Model of Auroral Transport and Its Effects in the Ionosphere

Earth and Space Science, Volume 13, Issue 7, July 2026.
Abstract Auroral transport models (ATMs) play an important role in quantitative studies of optical auroras, their driving mechanisms, and their effects on the ionosphere and thermosphere. TREx‐ATM was initially developed as the support model for the Transition Region Explorer (TREx) mission, and has gained increasing applications in the community in ...
Jun Liang, E. Donovan, E. Spanswick, C. Gabrielse, D. Chaddock, J. Houghton   +5 more
wiley   +1 more source

Image quality and metal artifact reduction in total hip arthroplasty CT: deep learning-based algorithm versus virtual monoenergetic imaging and orthopedic metal artifact reduction

European Radiology Experimental
Background To compare image quality, metal artifacts, and diagnostic confidence of conventional computed tomography (CT) images of unilateral total hip arthroplasty patients (THA) with deep learning-based metal artifact reduction (DL-MAR) to conventional
Mark Selles, Ruud H. H. Wellenberg, Derk J. Slotman, Ingrid M. Nijholt, Jochen A. C. van Osch, Kees F. van Dijke, Mario Maas, Martijn F. Boomsma   +7 more
doaj   +1 more source

Comparison of Low‐Iodine Concentration Quantification Accuracy and Contrast‐To‐Noise Ratio Across Three Dual‐Energy CT Techniques: A Phantom Study

Journal of Medical Radiation Sciences, Volume 73, Issue 2, Page 224-232, June 2026.
Using a clinical abdominal CT protocol, all three DECT techniques accurately quantified iodine. Rapid kV‐switching achieved the lowest detectable and quantifiable iodine concentrations, while dual‐layer DECT provided the highest normalised contrast‐to‐noise ratio on 40‐keV virtual monoenergetic images.
Chonsitron Sirituenlee, Sirapasson Kraison, Paweena Wongpan, Pawitiya Supawarapong, Teeraphat Pataraphitakpong, Supannika Kawvised, Samrit Kittipayak, Monchai Phonlakrai   +7 more
wiley   +1 more source

Advanced virtual monoenergetic imaging algorithm for lower extremity computed tomography angiography: effects on image quality, artifacts, and peripheral arterial disease evaluation [PDF]

, 2023
PURPOSETo investigate the image quality of lower extremity computed tomography angiography (LE-CTA) using a reconstruction algorithm for monoenergetic images (MEIs) to evaluate peripheral arterial disease (PAD) at different kiloelectron volt (keV) levels.
Ki Hyun Lee, Jin Mo Kang, Jeong Ho Kim, Suyoung Park, So Hyun Park, Jung Han Hwang, Ji Hoon Shin, Seong Yong Pak   +7 more
core   +1 more source

Assessment of metal artifacts from titanium wrist prostheses: photon-counting versus energy-integrating detector CT

European Radiology Experimental
Background We compared photon-counting detector computed tomography (PCD-CT) polyenergetic images, PCD-CT virtual monoenergetic images (VMI), and energy-integrating detector computed tomography (EID-CT) polyenergetic images regarding bone visualization ...
Nina Kämmerling, Simon Farnebo, Mårten Sandstedt, Ronald Booij, Anders Persson, Erik Tesselaar   +5 more
doaj   +1 more source

The utility of a dual-phase, dual-energy CT protocol in patients presenting with overt gastrointestinal bleeding

Acta Radiologica Open, 2021
Background Due to their easy accessibility, CT scans have been increasingly used for investigation of gastrointestinal (GI) bleeding. Purpose To estimate the performance of a dual-phase, dual-energy (DE) GI bleed CT protocol in patients with overt GI ...
Payam Mohammadinejad MD, Lukasz Kwapisz MD, Jeff L Fidler MD, Shannon P Sheedy MD, Jay P Heiken MD, Ashish Khandelwal MD, Michael L Wells MD, Adam T Froemming MD, Stephanie L Hansel MD, Yong S Lee PhD, Akitoshi Inoue MD, Ahmed F Halaweish PhD, Cynthia H McCollough PhD, David H Bruining MD, Joel G Fletcher MD   +14 more
doaj   +1 more source