Generalized (non-Markovian) diffusion equations with different memory kernels and subordination schemes based on random time change in the Brownian diffusion process are popular mathematical tools for description of a variety of non-Fickian diffusion processes in physics, biology, and earth sciences. Some of such processes (notably, the fluid limits of continuous time random walks) allow for either kind of description, but other ones do not. In the present work we discuss the conditions under which a generalized diffusion equation does correspond to a subordination scheme, and the conditions under which a subordination scheme does possess the corresponding generalized diffusion equation. Moreover, we discuss examples of random processes for which only one, or both kinds of description are applicable.
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http://dx.doi.org/10.1103/PhysRevE.103.032133 | DOI Listing |
Med Phys
January 2025
Paul Albrechtsen Research Institute, CancerCare Manitoba, Winnipeg, Canada.
Background: The treatment of glioblastomas (GBM) with radiation therapy is extremely challenging due to their invasive nature and high recurrence rate within normal brain tissue.
Purpose: In this work, we present a new metric called the tumour spread (TS) map, which utilizes diffusion tensor imaging (DTI) to predict the probable direction of tumour cells spread along fiber tracts. We hypothesized that the TS map could serve as a predictive tool for identifying patterns of likely recurrence in patients with GBM and, therefore, be used to modify the delivery of radiation treatment to pre-emptively target regions at high risk of tumour spread.
J Glob Antimicrob Resist
January 2025
Infectious Disease Clinic, Dept. Of Biomedical Sciences and Public Health, Polytechnic University of Marche, Ancona, Italy; Infectious Disease, Azienda Sanitaria Pesaro-Urbino, Pesaro, Italy.
Objectives: KPC-producing Klebsiella pneumoniae (KPC-Kp) is a great cause of concern and it is often associated with bloodstream infections (BSIs) and a high mortality rate. We identified the risk factors of KPC-Kp BSIs observed in three Italian hospitals and studied the epidemiology of KPC-Kp strains.
Methods: We performed a retrospective analysis of KPC-Kp BSIs from 2014 to 2019 in three hospitals in Central Italy (Ancona, Pesaro-Fano, and Perugia).
Magn Reson Imaging
January 2025
Department of Radiology, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, NY, USA. Electronic address:
Purpose: Diffusion-weighted arterial spin labeling (DW-ASL) MRI has been proposed to determine the rate of water exchange (K) across the blood brain barrier (BBB). This study aims to further evaluate K MRI by comparing it with standard dynamic contrast-enhanced (DCE) MRI and histology in association with mannitol-induced disruption of the BBB.
Methods: DW-ASL was measured using a multiple b-value MRI protocol in normal rats at three post-labeling delays (N = 19), before and after intra-carotid injection of mannitol to disrupt BBB in one hemisphere (N = 13).
Med Image Anal
January 2025
School of Biomedical Engineering and Imaging Sciences, King's College London, UK. Electronic address:
Atrial fibrillation (AF), impacting nearly 50 million individuals globally, is a major contributor to ischaemic strokes, predominantly originating from the left atrial appendage (LAA). Current clinical scores like CHA₂DS₂-VASc, while useful, provide limited insight into the pro-thrombotic mechanisms of Virchow's triad-blood stasis, endothelial damage, and hypercoagulability. This study leverages biophysical computational modelling to deepen our understanding of thrombogenesis in AF patients.
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January 2025
Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh, 11541, Saudi Arabia.
The ongoing challenge of water pollution necessitates innovative approaches to remove organic contaminants from wastewater. In this work, new two-dimensional S-scheme heterojunction photocatalysts BiO/CdS and MoS/BiO/CdS that are intended for the effective photocatalytic destruction of 4-nitrophenol, a dangerous organic pollutant, are synthesized and characterized. Utilizing a solvothermal method, successfully generated these ternary nanocomposites, which were characterized through various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high resolution transmission electronmicroscopy (HRTEM), Brunauer-Emmett-Telle (BET) and diffuse reflectance spectroscopy (DRS).
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