Aqueous phase behavior and structures of phases were studied in systems containing sodium poly(styrenesulfonate), NaPSS, and complex salt CTAPSS, formed between cetyltrimethylammonium cations, CTA+, and PSS- anions. It was shown that hydrophobic interaction of the polyion styrene groups with surfactant aggregates, which supports the strong electrostatic attraction between CTA+ and PSS-, has a significant effect on phase behavior and structures. Only the disordered micellar (L1) and the ordered hexagonal (H1) phase were found that are connected over a broad two-phase region of L1-H1 coexistence. At water contents above 60 wt%, CTAPSS is easily dissolved in proportion to the amount of added NaPSS, whereas at lower water contents a large excess of NaPSS is needed to dissolve CTAPSS. Phase separation in the two-phase region is controlled by two tendencies: (i) to maximize the contact between the hydrophobic groups and micelles (assisted by hydrophobic interaction) and (ii) to form as dense phase as possible (assisted by both, electrostatic and hydrophobic interactions). Structural characteristics of soluble non-stoichiometric complexes from the L1 phase show that hydrophobic interaction contributes also to a relatively small size of PSS-induced micelles and leads to a network-like association between PSS chains in which micelles serve as cross-links.
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Arthritis Res Ther
December 2024
Department of Rheumatology, Hospital Universitario de Bellvitge. Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain.
Objective: To investigate differences in arterial involvement patterns on F-FDG PET-CT between predominant cranial and isolated extracranial phenotypes of giant cell arteritis (GCA).
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BMJ Open
December 2024
Graduate Institute of Sport, Leisure and Hospitality Management, National Taiwan Normal University, Taipei, Taiwan.
Objective: Phase angle (PhA) is a prognostic factor for predicting and monitoring geriatric syndromes. However, multiple factors associated with increased PhA values as an outcome remain unclear in the older population. This study aimed to examine the association of socio-demographic, anthropometric and behavioural factors with PhA among older Taiwanese adults.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
State Key Laboratory of Resource Insects, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing 400715, China. Electronic address:
Traditional wound closure methods often present several issues, including additional puncture wounds, adverse effects from anesthesia, and noticeable scarring. Inspired by embryonic wound healing, a Janus hydrogel (PG/Au-Asp@PCM) is designed to manipulate non-invasive wound closure by photothermal-responsive self-contraction of PG/Au-Asp@PCM, which is attributed to the shape memory behavior of PG/Au-Asp@PCM under near-infrared (NIR). Wherein, gelatin acts as a thermally reversible "switch" and polyacrylamide creates stable and cross-linked "net-points".
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2024
Cleveland Diagnostics, 3615 Superior Ave., Cleveland, OH, 44114, USA. Electronic address:
The partition coefficient of human serum albumin (HSA) was analyzed in the PEG600-Dex70, 0.15 M NaCl/KCl in 0.01 M Na/K phosphate buffer, pH 7.
View Article and Find Full Text PDFMicron
December 2024
Department of Chemical and Materials Engineering, The University of Auckland, New Zealand. Electronic address:
This study investigates the effect of pre-deformation by cold rolling after solution annealing on the microstructure and properties of the fine-grained Al-Li alloy 2A97. Electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize grain boundaries, dislocations, precipitates and calculate their contribution to strength. It is found that the changes in precipitation behavior predominantly account for the enhanced tensile properties observed in the deformed alloys, where yield and tensile strengths are increased by 85 MPa and 63 MPa, respectively.
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