Dilute solutions of asymmetric polystyrene/poly(methyl methacrylate) (PS/PMMA) mixtures in toluene and tetrahydrofuran (THF) are investigated by static and dynamic light scattering (SLS and DLS). Both solvents are good solvents for each of the two polymers. In toluene, the PMMA refractive index increment is close to zero and SLS provides a direct measurement of the PS static scattering functions. DLS correlatively leads to a single relaxation mode connected with these PS chains. Contrarily, two modes well separated in time are observed for identical PS/PMMA mixtures in THF. Scattering from the PMMA chains is no longer negligible and partial static scattering functions can only be obtained through SLS-DLS combination. For identical polymer concentration and PS/PMMA mixture composition, PS scattering functions are then found to be different in both solvents. The difference increases with concentration and is only partly due to distinct thermodynamic parameters according to the solvent. PMMA scattering functions lead to similar conclusions. The Random Phase Approximation (RPA) describes all scattering functions. However, the SLS-DLS combination affords a reasonable approximation for extracting the partial static scattering functions only for the lowest concentrations, i.e. provided the cross polymer correlation term remains negligible.
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http://dx.doi.org/10.1140/epje/i2019-11921-9 | DOI Listing |
Sensors (Basel)
December 2024
TDA Research Inc., Golden, CO 80403, USA.
Here we describe the synthesis and evaluation of a molecular corrosion sensor that can be applied in situ in aerospace coatings, then used to detect corrosion after the coating has been applied. A pH-sensitive molecule, 4-mercaptopyridin (4-MP), is attached to a gold nanoparticle to allow surface-enhanced Raman-scattering (SERS) for signal amplification. These SERS nanoparticles, when combined with an appropriate micron-sized carrier system, are incorporated directly into an MIL-SPEC coating and used to monitor the process onset and progression of corrosion using pH changes occurring at the metal-coating interface.
View Article and Find Full Text PDFNutrients
December 2024
Department of Food Technology and Assessment, Institute of Food Sciences, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159 C, 02-776 Warsaw, Poland.
Background/objectives: There is scattered information in the scientific literature regarding the characterization of probiotic bacteria found in fermented milk beverages and the beneficial effects of probiotic bacteria on human health. Our objective was to gather the available information on the use of probiotic bacteria in the prevention of civilization diseases, with a special focus on the prevention of obesity, diabetes, and cancer.
Methods: We carried out a literature review including the following keywords, either individually or collectively: lactic acid bacteria; probiotic bacteria; obesity; lactose intolerance; diabetes; cancer protection; civilization diseases; intestinal microbiota; intestinal pathogens.
Int J Mol Sci
January 2025
Department of Clinical Biochemistry, University Hospital Southampton NHS Foundation Trust, Southampton General Hospital, Southampton SO16 6YD, UK.
From fertilisation to delivery, calcium must be transported into and within the foetoplacental unit for intracellular signalling. This requires very rapid, precisely located Ca transfers. In addition, from around the eighth week of gestation, increasing amounts of calcium must be routed directly from maternal blood to the foetus for bone mineralisation through a flow-through system, which does not impact the intracellular Ca concentration.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea.
This study utilized a genome-wide association study (GWAS) to investigate the genetic variations linked to the risk of hepatitis B virus (HBV) reactivation in patients who have undergone liver transplantation (LT), aiming to enhance understanding and improve clinical outcomes. Genotyping performed on a selected patients from the Korean Organ Transplantation Registry (KOTRY) data using high-throughput platforms with the Axiom Korea Biobank array 1.1.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Chemistry, Faculty of Sciences, Canakkale Onsekiz Mart University, Terzioglu Campus, 17100 Canakkale, Turkey.
Hematoxylin (HT) is a natural staining dye used in histopathology, often combined with Eosin for H&E staining. A poly(hematoxylin-co-l-lysine) (p(HT-co-l)) nanonetwork was synthesized through a one-step Mannich condensation reaction using formaldehyde as a linking agent. The resulting p(HT-co-l) nanogels had an average size of about 200 nm and exhibited a smooth surface and desirable functional groups such as -OH, -NH, and -COOH, as recognized by FT-IR analysis.
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