Although the network dynamics and mechanical properties of poly(butylene terephthalate) vitrimers can to some extent be controlled via chemical and physical approaches, it remains a challenge to be able to process PBT vitrimers with the same processing conditions via, for example, injection molding as neat PBT. Here, it is shown that the use of protected pentaerythritol as a latent cross-linker and the use of a Zn(II) transesterification catalyst allows for the in situ dynamic network formation in PBT during processing, with a delayed onset of gelation. This process can be controlled by adjusting the processing temperature, (protected) cross-linker content, and the type of protection group. This solvent-free deprotection strategy opens the way to high production rates of PBT vitrimer products via injection molding with the combination of low viscosity during processing and vitrimer characteristics in the final product.
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http://dx.doi.org/10.1002/marc.201800356 | DOI Listing |
JAMA Netw Open
January 2025
Alzheimer Center Limburg, Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.
Importance: Baseline cerebral microbleeds (CMBs) and APOE ε4 allele copy number are important risk factors for amyloid-related imaging abnormalities in patients with Alzheimer disease (AD) receiving therapies to lower amyloid-β plaque levels.
Objective: To provide prevalence estimates of any, no more than 4, or fewer than 2 CMBs in association with amyloid status, APOE ε4 copy number, and age.
Design, Setting, And Participants: This cross-sectional study used data included in the Amyloid Biomarker Study data pooling initiative (January 1, 2012, to the present [data collection is ongoing]).
J Comput Neurosci
January 2025
Program in Neuroscience, Indiana University Bloomington, Bloomington, IN, USA.
Hippocampal representations of space and time seem to share a common coding scheme characterized by neurons with bell-shaped tuning curves called place and time cells. The properties of the tuning curves are consistent with Weber's law, such that, in the absence of visual inputs, width scales with the peak time for time cells and with distance for place cells. Building on earlier computational work, we examined how neurons with such properties can emerge through self-supervised learning.
View Article and Find Full Text PDFMol Biol Rep
January 2025
Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector 62, Noida, UP, 201309, India.
Metabolic reprogramming stands out as a defining characteristic of cancer, including glioblastoma (GB), enabling tumor cells to overcome growth and survival challenges in adverse conditions. The dysregulation of metabolic processes in GB is crucial to its pathogenesis, influencing both tumorigenesis and the disease's invasive tendencies. This altered metabolism supplies essential energy substrates for uncontrolled cell proliferation and also creates an immunosuppressive microenvironment, complicating conventional therapies.
View Article and Find Full Text PDFGut Microbes
December 2025
Department of Microbiology, Immunology & Molecular Genetics, University of Texas Health San Antonio, San Antonio, TX, USA.
The probiotic impact of microbes on host metabolism and health depends on both host genetics and bacterial genomic variation. is the predominant human gut commensal emerging as a next-generation probiotic. Although this bacterium exhibits substantial intraspecies diversity, it is unclear whether genetically distinct strains might lead to functional differences in the gut microbiome.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill 27599, United States.
Architecturally hindered crystallization of bottlebrush graft copolymers offers a reaction- and solvent-free pathway for creating injectable elastomers with tissue-mimetic softness. Currently, injectable materials involve solvents and chemical reactions, leading to uncontrolled swelling, leaching of unreacted moieties, and side reactions with tissue. To address this issue, bottlebrush copolymers with a poly(ethylene glycol) (PEG) amorphous block and crystallizable poly(lactic acid) (PLA) grafted chains (A--B) were synthesized, with grafted chains of controlled length arranged along the backbone at controlled spacing.
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