The CoSAXS beamline at the MAX IV Laboratory is a modern multi-purpose (coherent) small-angle X-ray scattering (CoSAXS) instrument, designed to provide intense and optionally coherent illumination at the sample position, enabling coherent imaging and speckle contrast techniques. X-ray tracing simulations used to design the beamline optics have predicted a total photon flux of 10-10 photons s and a degree of coherence of up to 10% at 7.1 keV. The normalized degree of coherence and the coherent flux of this instrument were experimentally determined using the separability of a ptychographic reconstruction into multiple mutually incoherent modes and thus the Coherence in the name CoSAXS was verified. How the beamline can be used both for coherent imaging and XPCS measurements, which both heavily rely on the degree of coherence of the beam, was demonstrated. These results are the first experimental quantification of coherence properties in a SAXS instrument at a fourth-generation synchrotron light source.
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http://dx.doi.org/10.1107/S1600577521009140 | DOI Listing |
BMC Psychol
January 2025
Department of Health Policy&Management, Tabriz Health Services Management Research Center, School of Management and Medical Informatics, Tabriz University of Medical Sciences, Tabriz, Iran.
Background: Mental disorders represent a significant global health concern, accounting for a substantial proportion of disabilities worldwide. Given its significance, it has consistently been a priority for health policy makers. The aim was to provide a comprehensive assessment of mental disorder-related policy events and related interventions in Iran.
View Article and Find Full Text PDFBMC Ophthalmol
January 2025
College of Optometry, University of Houston College of Optometry, 4401 Martin Luther King Blvd, 77204-2020, Houston, TX, USA.
Background: This study evaluates retinal oxygen saturation and vessel density within the macula and correlates these measures in controls and subjects with type 2 diabetes (DM) with (DMR) and without (DMnR) retinopathy. Changes in retinal oxygen saturation have not been evaluated regionally in diabetic patients.
Methods: Data from seventy subjects (28 controls, 26 DMnR, and 16 DMR were analyzed.
Eye (Lond)
January 2025
Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.
Purpose: To determine how Hardy-Rand-Rittler (HRR) colour vision testing correlates with visual functional and structural assessments in Cone and Cone-Rod Dystrophy.
Methods: Thirty-four Cone and 69 Cone-Rod Dystrophy patients diagnosed by electroretinography (ERG) at the Save Sight Institute in Sydney were included in a retrospective analysis. Each patient's HRR colour vision test scores were compared with markers of cone and rod system function including visual acuity (VA), ERG responses, changes on Spectral Domain Optical Coherence Tomography (OCT) and Fundus Autofluorescence.
Struct Dyn
January 2025
Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
Sub-ångström spatial resolution of electron density coupled with sub-femtosecond to few-femtosecond temporal resolution is required to directly observe the dynamics of the electronic structure of a molecule after photoinitiation or some other ultrafast perturbation, such as by soft X-rays. Meeting this challenge, pushing the field of quantum crystallography to attosecond timescales, would bring insights into how the electronic and nuclear degrees of freedom couple, enable the study of quantum coherences involved in molecular dynamics, and ultimately enable these dynamics to be controlled. Here, we propose to reach this realm by employing convergent-beam x-ray crystallography with high-power attosecond pulses from a hard-x-ray free-electron laser.
View Article and Find Full Text PDFWe derive the Goos-Hänchen (GH) and Imbert-Fedorov (IF) shifts of random electromagnetic beams with arbitrary state and degree of polarization and spatial coherence. Further, we demonstrate the general formalism by calculating analytic expressions for the GH and IF shifts of an electromagnetic Gaussian Schell-model (EGSM) beam and show that the GH shifts may exist irrespective of the degree and state of polarization of the beam, while the IF shifts vanish when the beam is either s or p polarized or completely unpolarized. In addition, the spatial coherence width of the EGSM beam is found to influence only the angular GH and IF shifts.
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