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6,6,12-Graphyne is an all-carbon network formally generated by interspersing sp- and sp-hybridized carbon atoms between the carbon hexagons of graphene. Tetraethynylethene (TEE) is one structural unit that can be identified as bridging the benzene rings in 6,6,12-graphyne. Here we present the synthesis by stepwise Sonogashira couplings of TEE scaffolds that can be considered as small model systems of 6,6,12-graphyne segments. Electrochemical studies of the scaffolds revealed that they are weaker electron acceptors than related, but smaller, radiaannulene oligomers that were previously studied as relevant model systems of other 6,6,12-graphyne segments. The connectivity of the TEE units in these acyclic oligomers plays a role for their acceptor strengths according to experiments and quantum-chemical calculations. Moreover, optical studies reveal redshifted longest-wavelength absorptions as the oligomer length increases, but only to a small degree when moving from dimer to trimer structures. Experimental results were complemented by calculated absorption and redox properties.
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http://dx.doi.org/10.1002/chem.202500360 | DOI Listing |
Mol Ecol
September 2025
State Key Laboratory of Soil and Water Conservation and Desertification Control, College of Soil and Water Conservation Science and Engineering, Northwest A&F University, Shaanxi, People's Republic of China.
Increasing evidence indicates that the loss of soil microbial α-diversity triggered by environmental stress negatively impacts microbial functions; however, the effects of microbial α-diversity on community functions under environmental stress are poorly understood. Here, we investigated the changes in bacterial and fungal α- diversity along gradients of five natural stressors (temperature, precipitation, plant diversity, soil organic C and pH) across 45 grasslands in China and evaluated their connection with microbial functional traits. By quantifying the five environmental stresses into an integrated stress index, we found that the bacterial and fungal α-diversity declined under high environmental stress across three soil layers (0-20 cm, 20-40 cm and 40-60 cm).
View Article and Find Full Text PDFAlzheimers Dement
September 2025
Alzheimer's Disease Convergence Research Center, Samsung Medical Center, Seoul, South Korea.
Introduction: We developed and validated age-related amyloid beta (Aβ) positron emission tomography (PET) trajectories using a statistical model in cognitively unimpaired (CU) individuals.
Methods: We analyzed 849 CU Korean and 521 CU non-Hispanic White (NHW) participants after propensity score matching. Aβ PET trajectories were modeled using the generalized additive model for location, scale, and shape (GAMLSS) based on baseline data and validated with longitudinal data.
Mol Ther Methods Clin Dev
June 2025
Eisai Co., Ltd., Tsukuba Research Laboratories, 5-1-3, Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
Liver-humanized chimeric mice (PXB-mice) are widely utilized for predicting human pharmacokinetics (PK) and as human disease models. However, residual metabolic activity of mouse hepatocytes in chimeric mice can interfere with accurate human PK estimation. Lipid nanoparticle (LNP)-formulated small interfering RNA (siRNA) treatment makes it possible to eliminate the shortcomings of chimeras and create new models.
View Article and Find Full Text PDFFront Rehabil Sci
August 2025
Department of Neurosurgery, David Geffen School of Medicine, University of California, Los Angeles, CA, United States.
Introduction: Spinal cord injury (SCI) presents a significant burden to patients, families, and the healthcare system. The ability to accurately predict functional outcomes for SCI patients is essential for optimizing rehabilitation strategies, guiding patient and family decision making, and improving patient care.
Methods: We conducted a retrospective analysis of 589 SCI patients admitted to a single acute rehabilitation facility and used the dataset to train advanced machine learning algorithms to predict patients' rehabilitation outcomes.