The single shot based coherence properties of hard x-ray pulses from the Linac Coherent Light Source (LCLS) were measured by analyzing coherent diffraction patterns from nano-particles and gold nanopowder. The intensity histogram of the small angle x-ray scattering ring from nano-particles reveals the fully transversely coherent nature of the LCLS beam with a number of transverse mode 〈Ms〉 = 1.1. On the other hand, the speckle contrasts measured at a large wavevector yields information about the longitudinal coherence of the LCLS radiation after a silicon (111) monochromator. The quantitative agreement between our data and the simulation confirms a mean coherence time of 2.2 fs and a x-ray pulse duration of 29 fs. Finally the observed reduction of the speckle contrast generated by x-rays with pulse duration longer than 30 fs indicates ultrafast dynamics taking place at an atomic length scale prior to the permanent sample damage.
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http://dx.doi.org/10.1364/OE.21.024647 | DOI Listing |
NMR Biomed
February 2025
MR Methodology, Department for Diagnostic and Interventional Neuroradiology, University of Bern, Bern, Switzerland.
The purpose of this study was to produce metabolite-specific T and concentration maps in a clinically compatible time frame. A multi-TE 2D MR spectroscopic imaging (MRSI) experiment (multi-echo single-shot MRSI [MESS-MRSI]) deployed truncated and partially sampled multi-echo trains from single scans and was combined with simultaneous multiparametric model fitting. It was tested in vivo for the brain in five healthy subjects.
View Article and Find Full Text PDFJ Magn Reson Imaging
January 2025
Department of Radiology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.
Background: Bladder injury during cesarean delivery (CD) in pregnant women with severe placenta accreta spectrum (PAS) disorders mostly occurs in the dissection of vesico-uterine space. Placental MRI may help to assess the risk of bladder injury preoperatively.
Purpose: To identify the high-risk MRI signs of bladder injury during CD in women with severe PAS.
J Electrocardiol
January 2025
Department of Cardiology, University Hospitals of Leicester NHS Trust, Glenfield Hospital, Leicester, UK; Department of Cardiovascular Sciences, Clinical Science Wing, University of Leicester, Glenfield Hospital, Leicester, UK; National Institute for Health Research Leicester Research Biomedical Centre, Leicester, UK.
Background: Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) can be performed using one-shot cryoballoon ablation (cryo) or point-by-point radiofrequency ablation (RF). This study compares the changes in P-wave parameters between both ablation methods.
Methods: This single-centre retrospective study included contact force RF and second-generation cryo for PAF between 2018 and 2019.
J Forensic Sci
January 2025
Netherlands Forensic Institute, Den Haag, Netherlands.
In shooting incident reconstructions, forensic examiners usually deal with scenes involving short-range trajectories, typically ≤30 m. In situations such as this, a linear trajectory reconstruction model is appropriate. However, a forensic expert can also be asked to estimate a shooter's position by reconstructing a long-range trajectory where the bullet's path becomes arced as a result of gravity and the greater time in flight.
View Article and Find Full Text PDFCureus
December 2024
Emergency Medicine, Henry Ford Health System, Detroit, USA.
Shoulder arthroscopic and arthroplastic surgeries are associated with significant postoperative pain, which can delay recovery and increase opioid consumption. Interscalene blocks (ISBs) are a commonly used method to manage this pain, either as single-shot injections or continuous catheter infusions (CISBs). This review synthesizes findings from studies conducted in the past five years, comparing the efficacy, complications, and outcomes of single-shot ISBs versus CISBs for postoperative pain management in shoulder surgeries.
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