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A series of gallium and indium complexes containing a bis(imino)phenolate ligand framework were synthesized and completely characterized with different spectroscopic techniques. The molecular structures of a few complexes were determined using single crystal X-ray diffraction studies. These compounds were found to be extremely active towards the bulk ring opening polymerization (ROP) of lactides yielding polymers with high number average molecular weight (Mn) and controlled molecular weight distributions (MWDs). The neutral complexes produce isotactic enriched poly(lactic acid) (PLA) from rac-lactide (rac-LA) under melt conditions, whereas the ionic complex produces atactic PLA. The polymerizations are controlled, as evidenced by the narrow molecular distribution (MWDs) of the isolated polymers in addition to the linear nature of number average molecular weight (Mn) versus conversion plots with variations in monomer to catalyst ratios. The kinetic and mechanistic studies associated with these polymerizations have been performed.
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http://dx.doi.org/10.1039/c5dt00811e | DOI Listing |
J Biomol NMR
September 2025
Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA.
Biomolecular dynamics in the microsecond-to-millisecond (µs-ms) timescale are linked to various biological functions, such as enzyme catalysis, allosteric regulation, and ligand recognition. In solution state NMR, Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion experiments are commonly used to probe µs-ms timescale motions, providing detailed kinetic, thermodynamic, and mechanistic information at the atomic level. For investigating conformational dynamics in high-molecular-weight biomolecules, methyl groups serve as ideal probes due to their favorable relaxation properties, and C CPMG relaxation dispersion is widely employed for characterizing dynamics in selectively CH-labeled samples.
View Article and Find Full Text PDFPhysiol Plant
September 2025
School of Forestry and Grassland Science, Ningxia University, Yinchuan, China.
Using high- and low-surface flatness fruits of Ziziphus jujuba Mill. cv. "Lingwuchangzao" at different developmental stages as test materials, this study examined the mechanisms underlying variations in fruit appearance and internal quality.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
Department of Chemistry and Biochemistry, Miami University, 651 E High St, Oxford, OH, 45056, USA.
Photodegradable nanoparticles with sphere, worm, and vesicle morphologies were synthesized following polymerization induced self-assembly (PISA), incorporating a photoresponsive phenyl vinyl ketone (PVK) block and a nonphoto responsive 2-hydroxypropyl methacrylamide (HPMA) block. The photodegradation of nanoparticles under UV revealed that the initial shapes of sphere and vesicle particles are retained even until 7 h and after 24 h of photo-induced degradation, respectively, despite a significant reduction in molecular weight (M). This could be due to the assembly of degraded PVK fragments in the hydrophobic region, maintaining the relative hydrophilic to hydrophobic ratio.
View Article and Find Full Text PDFMedicine (Baltimore)
September 2025
Department of Histology and Embryology, Faculty of Medicine, Dicle University, Diyarbakir, Turkey.
Excessive gestational weight gain (GWG) is associated with various adverse pregnancy outcomes, including disruption of placental function and fetal development. Iron transport through the placenta is crucial for fetal growth, and transferrin receptor 2 (TfR2) plays a key role in iron homeostasis. However, the effect of excessive GWG on placental TfR2 expression and neonatal iron parameters remains unclear.
View Article and Find Full Text PDFMedicine (Baltimore)
September 2025
The Unit of Pathogenic Fungal Infection & Host Immunity, CAS Key Laboratory of Molecular Virology and Immunology, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai, China.
Rationale: Cytomegalovirus (CMV) is a DNA virus from the herpesvirus family that is widespread among humans. Very low birth weight infants (VLBWI) are particularly susceptible to postnatal CMV infection due to their compromised immune systems. The clinical manifestations of postnatal CMV infection are often nonspecific, which complicates early detection and may lead to multi-organ dysfunction and long-term sequelae.
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