Dielectric spectroscopy is used to measure the complex permittivity of 200 and 100 nm diameter polystyrene latex suspended in potassium chloride (KCl) solutions over the frequency range 10(4)-10(7) Hz as a function of particle volume fraction (ϕ) and ionic strength. Dilute suspension dielectric spectra are in excellent agreement with electrokinetic theory. A volume fraction dependence of the dielectric increment is observed for low electrolyte concentrations (0.01, 0.05, and 0.1 mM) above ϕ ≈ 0.02. This deviation from the dilute theory occurs at a critical frequency ω* that is a function of volume fraction, particle size, and ionic strength. The dielectric increment of suspensions at the highest salt concentration (1 mM) shows no volume fraction dependence up to ϕ = 0.09. Values of ω* are collapsed onto a master curve that accounts for the length and time scales of ion migration between neighboring particles. The measured conductivity increment is independent of volume fraction and agrees with theory after accounting for added counterions and nonspecific adsorption.
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http://dx.doi.org/10.1021/la301876w | DOI Listing |
Radiat Oncol
January 2025
Department of Neurosurgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Purpose: In this retrospective study, we aimed to evaluate the efficacy and incidence of radiation-induced brain necrosis (RBN) after volumetric modulated arc therapy-based stereotactic irradiation (VMAT-STI) for brain metastases.
Methods: In the 220 brain metastatic lesions included between January 2020 and June 2022, there were 1-9 concurrently treated lesions (median 1). A biologically effective dose (BED)10 of 80 Gy and a reduced BED10 of 50 Gy were prescribed to the gross tumor volume (GTV) and planning target volume (PTV) (PTV = GTV + 3 mm) margins, respectively.
Mol Psychiatry
January 2025
Department of Radiology, NYU Grossman School of Medicine, New York, NY, USA.
Myelin abnormalities in white matter have been implicated in the pathophysiology of psychotic spectrum disorders (PSD), which are characterized by brain dysconnectivity as a core feature. Among evidence from in vivo MRI studies, diffusion imaging findings have largely supported disrupted white matter integrity in PSD; however, they are not specific to myelin changes. Using a multimodal imaging approach, the current study aimed to further delineate myelin and microstructural changes in the white matter of a young PSD cohort.
View Article and Find Full Text PDFMol Imaging Biol
January 2025
Yale PET Center, Yale School of Medicine, New Haven, USA.
Purpose: The sphingosine-1-phosphate receptor-1 (S1PR) is involved in regulating responses to neuroimmune stimuli. There is a need for S1PR-specific radioligands with clinically suitable brain pharmcokinetic properties to complement existing radiotracers. This work evaluated a promising S1PR radiotracer, [F]TZ4877, in nonhuman primates.
View Article and Find Full Text PDFSaudi Med J
January 2025
From the College of Medicine (Bin Abdu, Assiri, Altasan, Alghamdi, Alshelawy, Alqahtani, Aljabr, Alnahdi, Alhamzani, Alghamdi, Alzahrani, Alshahrani, Alzahrani, Alshalawi), King Saud Bin Abdulaziz University for Health Sciences; from the Department of Medicine (Bin Abdu, Assiri, Altasan, Alghamdi, Alshelawy, Alqahtani, Aljabr, Alnahdi, Alhamzani, Alghamdi, Alzahrani, Alshahrani, Alzahrani, Alshalawi), King Abdullah International Medical Research Center; and from the Emergency Department (Alshalawi), King Abdulaziz Medical City Riyadh, Kingdom of Saudi Arabia.
Objectives: To assess the clinical course and long-term outcomes of complicated and uncomplicated AM in Saudi Arabia. Acute myocarditis (AM) can have different presentations and outcomes based on different factors, one of which is left ventricular ejection fraction (LVEF).
Methods: Data from 382 patients with suspected AM, admitted between January 2016 and October 2023, were reviewed.
Circ J
January 2025
Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University.
Background: Accurate prediction of prognosis in transthyretin amyloid cardiomyopathy (ATTR-CM) is crucial for optimal treatment selection, including tafamidis, the only approved therapy for ATTR-CM. Although tafamidis has been proven to improve prognosis, the long-term serial changes in comprehensive parameters related to ATTR-CM, including cardiac biomarkers and imaging parameters, under tafamidis remain unknown.
Methods And Results: In this study, we used Cox regression analysis on data from 258 consecutive patients diagnosed with ATTR-CM at Kumamoto University to determine prognostic factors.
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