Results 21 to 30 of about 1,327,251 (363)

Identifying the 3FHL Catalog. VI. Swift Observations of 3FHL Unassociated Objects with Source Classification via Machine Learning [PDF]

ApJ 940 139 (2022), 2022
The Third Catalog of Hard Fermi Large Area Telescope Sources (3FHL) reports the detection of 1556 objects at E > 10 GeV. However, 177 sources remain unassociated and 23 are associated with a ROSAT X-ray detection of unknown origin. Pointed X-ray observations were conducted on 30 of these unassociated and unknown sources with Swift-XRT.
arxiv   +1 more source

Rational design of mechanically robust Ni-rich cathode materials via concentration gradient strategy

Nature Communications, 2021
Mechanical integrity issues are one of the main causes of limited long-term cycle stability for Ni-rich cathode materials. Here the authors analyse the roles of cobalt and manganese and utilise a concentration gradient design to mitigate these issues.
Tongchao Liu, Lei Yu, Jun Lu, Tao Zhou, Xiaojing Huang, Zhonghou Cai, Alvin Dai, Jihyeon Gim, Yang Ren, Xianghui Xiao, Martin V. Holt, Yong S. Chu, Ilke Arslan, Jianguo Wen, Khalil Amine   +14 more
doaj   +1 more source

Ultraluminous X-Ray Sources [PDF]

Annual Review of Astronomy and Astrophysics, 2017
We review observations of ultraluminous X-ray sources (ULXs). X-ray spectroscopic and timing studies of ULXs suggest a new accretion state distinct from those seen in Galactic stellar-mass black hole binaries. The detection of coherent pulsations indicates the presence of neutron-star accretors in three ULXs and therefore apparently super-Eddington ...
Kaaret, Philip, Feng, Hua, Roberts, Timothy P.   +2 more
openaire   +4 more sources

COMP Report: CPQR technical quality control guidelines for use of positron emission tomography/computed tomography in radiation treatment planning

Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022
Abstract Positron emission tomography with x‐ray computed tomography (PET/CT) is increasingly being utilized for radiation treatment planning (RTP). Accurate delivery of RT therefore depends on quality PET/CT data. This study covers quality control (QC) procedures required for PET/CT for diagnostic imaging and incremental QC required for RTP.
Ran Klein, Mike Oliver, Dan La Russa, John Agapito, Stewart Gaede, JeanPierre Bissonnette, Arman Rahmim, Carlos Uribe   +7 more
wiley   +1 more source

A small footprint couch‐top support device for image‐guided radiotherapy of heavy patients

Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022
Abstract Purpose Patients with body weights close to or above 400 lbs present unique challenges in radiation therapy since the weight limit of most treatment couches decreases as the couch‐top extends toward the treatment gantry. The purpose of this work was to develop a small footprint couch‐top support platform to safely perform image‐guided ...
Huixiao Chen, Kevin Morley, Ronnie Rodriguez, Emily Draeger, Muhammad Shafiq ul Hassan, Zhe (Jay) Chen   +5 more
wiley   +1 more source

Extragalactic X-ray Sources [PDF]

Nature, 1972
A review is given of the physical properties of extragalactic X-ray sources. The generation of X-rays as thermal bremsstrahlung, by the synchrotron mechanism or by Compton Scattering, is discussed. It is shown that each may be important depending on the circumstances.
K. BRECHER, G. R. BURBIDGE
openaire   +3 more sources

The application of multiple metrics in deformable image registration for target volume delineation of breast tumor bed

Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022
Abstract Background and purpose For postoperative breast cancer patients, deformable image registration (DIR) is challenged due to the large deformations and non‐correspondence caused by tumor resection and clip insertion. To deal with it, three metrics (fiducial‐, region‐, and intensity‐based) were jointly used in DIR algorithm for improved accuracy ...
Xin Xie, Yuchun Song, Feng Ye, Hui Yan, Shulian Wang, Xinming Zhao, Jianrong Dai   +6 more
wiley   +1 more source

X-RAY MONITORING OF ULTRALUMINOUS X-RAY SOURCES [PDF]

The Astrophysical Journal, 2009
X-ray monitoring observations were performed with the Swift observatory of the ultraluminous X-ray sources Holmberg IX X-1, NGC 5408 X-1, and NGC 4395 X-2 and also of the nuclear X-ray source in NGC 4395. Holmberg IX X-1 remains in the hard X-ray spectral state as its flux varies by a factor of 7 up to an (isotropic) luminosity of 2.8E40 erg/s.
Philip Kaaret, Hua Feng
openaire   +3 more sources

Joint application of hybrid iterative reconstruction and adaptive filters on neck‐and‐shoulder CT imaging: A clinical evaluation

Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022
Abstract Purpose To assess whether the joint application of hybrid iterative reconstruction (HIR) and an adaptive filter (AF) could reduce streak artifacts and improve image quality of neck‐and‐shoulder computed tomography (CT). Methods This study included 96 patients with suspicious neck lesions who underwent a routine nonenhanced scan on a 64‐slice ...
Wenfeng Jin, Yifei Ma, Dan Han, Xiaojie Xie, Weiyuan Zhang, Yan Wu, Guozhi Zhang   +6 more
wiley   +1 more source

Clinical commissioning of an adaptive radiotherapy platform: Results and recommendations

Journal of Applied Clinical Medical Physics, Volume 23, Issue 12, December 2022., 2022
Abstract Online adaptive radiotherapy platforms present a unique challenge for commissioning as guidance is lacking and specialized adaptive equipment, such as deformable phantoms, are rare. We designed a novel adaptive commissioning process consisting of end‐to‐end tests using standard clinical resources.
Kelly Kisling, Timothy D. Keiper, Daniela Branco, Grace Gwe‐Ya Kim, Kevin L Moore, Xenia Ray   +5 more
wiley   +1 more source