High free-volume copolymers were prepared via polycondensation with 2,3,5,6,-tetrafluoroterephthalonitrile (TFTPN) in which a portion of the 3,3,3',3'-tetramethyl-1,1'-spirobisindane (TTSBI) of PIM-1 was replaced with dibutyl anthracene maleimide (4bIII). An investigation of free volume using positron annihilation lifetime spectroscopy (PALS), and gas permeation measurements was carried out for the thin film composite copolymer membranes and compared to PIM-1. The average free volume hole size and the gas permeance of the copolymer membranes increased with decreasing TTSBI content in the copolymer.
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http://dx.doi.org/10.3390/membranes5020214 | DOI Listing |
J Clin Med
January 2025
Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy.
According to current guidelines, patients with heart valve disease should be followed by Heart Valve Clinics (HVCs). Regular quality analysis is a major prerequisite of an HVC's program, but few data have been reported so far. We retrospectively collected patients with isolated, native aortic valve stenosis who had been visited in our HVC at least once between 2021 and 2024.
View Article and Find Full Text PDFCancers (Basel)
January 2025
Department of Radiation Oncology, TUM School of Medicine and Health and Klinikum rechts der Isar, University Hospital of the Technical University of Munich, Ismaninger Straße 22, 81675 Munich, Germany.
Objectives: The present study aimed to compare the tumor growth delay between conventional radiotherapy (CRT) and the spatially fractionated modalities of microbeam radiation therapy (MRT) and minibeam radiation therapy (MBRT). In addition, we also determined the influence of beam width and the peak-to-valley dose ratio (PVDR) on tumor regrowth.
Methods: A549, a human non-small-cell lung cancer cell line, was implanted subcutaneously into the hind leg of female CD1 mice.
Cancers (Basel)
December 2024
Department of Gynecological Oncology, Centre for Gynecologic Oncology Amsterdam (C.G.O.A.), Amsterdam University Medical Center, 1081 HV Amsterdam, The Netherlands.
Background: Guidelines recommend the extension of the pelvic radiotherapy volume to the para-aortic region in locally advanced cervical cancer and ≥3 suspicious pelvic lymph nodes (PLN) on imaging. Whether this recommendation is also valid for clinically early stages is uncertain. The objective of this study was to investigate the para-aortic (PAO) lymph node recurrence rate in patients with early-stage cervical cancer, ≥3 metastatic PLN, and negative common iliac nodes after a radical hysterectomy followed by pelvic (chemo)radiotherapy without extension to the PAO region.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Division of Reproductive Sciences, Department of Obstetrics and Gynecology, Duke University School of Medicine, 701 West Main Street, Suite 510, Duke, P.O. Box 90534, Durham, NC 27701, USA.
The mortality rate of ovarian cancer (OC) remains the highest among female gynecological malignancies. Advanced age is the highest risk factor for OC development and progression, yet little is known about the role of the aged tumor microenvironment (TME). We conducted RNA sequencing and lipidomic analysis of young and aged gonadal adipose tissue from rat xenografts before and after OC formation.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011, USA.
The dielectric properties of polymers play a pivotal role in the development of advanced materials for energy storage, electronics, and insulation. This review comprehensively explores the critical relationship between polymer chain conformation, nanostructure, and dielectric properties, focusing on parameters such as dielectric constant, dielectric loss, and dielectric breakdown strength. It highlights how factors like chain rigidity, free volume, molecular alignment, and interfacial effects significantly influence dielectric performance.
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