The evolution of the adsorption energy of carbon monoxide (CO) molecules on palladium (Pd) clusters as function of Pd particle size from the molecular regime (less than ~100 atoms per particle) to the bulk regime has been revealed. This adsorption energy is retrieved from the residence time of CO molecules on the Pd clusters, measured by a pulsed molecular beam technique, versus temperature. Unprecedented accuracy on the determination of the particle size has been achieved here by using a regular array of metal clusters exhibiting a size dispersion down to the ultimate limit of a Poisson distribution. This allows getting rid of the convolution effects that generally occur when considering particles grown through other techniques.
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Alzheimers Dement
December 2024
Columbia University Irving Medical Center, New York, NY, USA.
Background: Glial cells exhibit distinct transcriptional responses to β-amyloid pathology in Alzheimer's disease (AD). While sophisticated single-cell based methods have revealed heterogeneous glial subpopulations in the human AD brain, the histological localization of these multicellular responses to AD pathology has not been fully characterized due to the loss of spatial information. Here, we combined spatial transcriptomics (ST) with immunohistochemistry to explore the molecular mechanisms in the neuritic plaque niche.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Department of Medicine (Biomedical Genetics), Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.
Background: Several viruses have been linked to Alzheimer disease (AD) by independent lines of evidence.
Method: Whole genome and whole exome sequences (WGS/WES) derived from brain (3,404 AD cases, 894 controls) and blood (15,612 AD cases, 24,544 controls) obtained from European ancestry (EU), African American (AA), Mexican (HMX), South Asian Indian (IND), and Caribbean Hispanic (CH) participants of the Alzheimer's Disease Sequencing Project (ADSP) and 276 AD cases 3,584 controls (all EU) from the Framingham Heart Study (FHS) that did not align to the human reference genome were aligned to viral reference genomes. A genome-wide association study (GWAS) for viral DNA load was conducted using PLINK software and regression models with covariates for sex, age, ancestry principal components, and tissue source.
Adv Mater
January 2025
Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China.
Catalysis remains a cornerstone of chemical research, with the active sites of catalysts being crucial for their functionality. Identifying active sites, particularly during the reaction process, is crucial for elucidating the relationship between a catalyst's structure and its catalytic property. However, the dynamic evolution of active sites within heterogeneous metal catalysts presents a substantial challenge for accurately pinpointing the real active sites.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, Anhui University, Hefei, Anhui 230601, P. R. China.
Icosahedral gold clusters with high-symmetry geometry and magic electronic shells are potential candidates for cluster-assembling, while their assembling rules are still awaiting further investigation. In this work, we use the all-metal icosahedral M@Au as a building block to assemble a series of bi-, tri-, tetra-, and penta-superatomic molecules with diverse superatomic bonding patterns via face-fusion, aiming to systemically explore the bonding rule of superatoms. Chemical bonding analyses indicate that these bi-, tri-, tetra-, and penta-superatomic molecules [M@Au] (M = Re, W, Ta, Ti, Hf, Ir, and Pt) can be considered electronic analogues to Cl, O, N, CO, O, CO, NCl, and CF molecules with single, double, triple, and multicenter bonds, respectively.
View Article and Find Full Text PDFBMC Pharmacol Toxicol
January 2025
Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences, Birjand, 9713643138, Iran.
Background: Cerebrovascular accidents are known as a great cause of morbidity and mortality worldwide. Although there are known risk factors for ischemic stroke, the cases that cannot be justified with these risk factors are increasing. Toxic metals as a potential risk factor for other diseases in humans are assessed in this study in the CVA group and compared to controls.
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