👤 Sangwon Wi

Rapid advancements in artificial intelligence have magnified the inherent bottlenecks and energy inefficiencies of conventional von Neumann architecture. To address these limitations, processing information in a highly parallel, memory-integrated manner mimicking the human brain, neuromorphic devices have emerged as a cornerstone of next-generation computing. Among these, optical-neuromorphic devices are particularly promising. By using light, they offer transformative advantages, such as high speed, massive bandwidth, and minimal signal interference. Accordingly, we propose long-persistent luminescence (LPL) materials as novel substrates for optically operative artificial synapses. We utilize AGa Show less

Low vitamin D levels are associated with an elevated risk of Alzheimer's disease (AD). Given the rising prevalence of diabetes and its association with AD, this study investigated whether vitamin D modulates amyloidogenesis and inflammation in the brains of diabetic mice. Five-week-old male C57BLKS/J- High dietary vitamin D levels attenuated neuronal necrosis in db/db mice. Hippocampal These findings suggest that vitamin D may exert neuroprotective effects on the hippocampus and PFC in diabetic mice by mitigating neuronal damage and suppressing amyloidogenic and inflammatory gene expression. Show less

Inhibition of amyloid precursor protein (APP) beta-site cleaving enzyme 1 (BACE1) has been a target for Alzheimer's disease (AD) therapeutic development. Here, we report our identification of APP-selective BACE1 (ASBI) inhibitors that are selective for APP as the substrate and BACE1 as the target enzyme. A known fluoro aminohydantoin (FAH) inhibitor compound was identified by screening a compound library for inhibition of BACE1 cleavage of a maltose binding protein (MBP)-conjugated-APPC125 substrate followed by optimization and IC50 determination using the P5-P5' activity assay. Optimization of the screening hit led to candidate FAH65, which displays selectivity for inhibition of APP cleavage with little activity against other BACE1 substrates neuregulin 1 (NRG1) or p-selectin glycoprotein ligand-1 (PSGL1). FAH65 shows little inhibitory activity against other aspartyl proteases cathepsin D (Cat D) and BACE2. FAH65 reduces BACE1 cleavage products soluble APPβ (sAPPβ) and the β C-terminal fragment (βCTF), as well as amyloid-β (Aβ) 1-40 and 1-42, both in vitro in cells and in vivo in an animal model of AD. In a murine model of AD, FAH65 improved the discrimination score in the Novel Object Recognition (NOR) memory testing paradigm. The active enantiomer of racemate FAH65, FAH65E(-), displays good brain-penetrance and target engagement, meriting further pre-clinical development as an ASBI that may reduce Aβ levels and overcome the deleterious effects of the non-selective BACE1 inhibitors that have failed in the clinic. FAH65E(-) has the potential to be a first-in-class oral therapy that could be used in conjunction with an approved anti-Aβ antibody therapy for AD. Show less

Neuromorphic computation draws inspiration from the remarkable features of the human brain including low energy consumption, parallelism, adaptivity, cognitive functions, and learning ability. These qualities hold the promise of unlocking groundbreaking computational techniques that surpass the limitations of traditional computing systems. This paper reports a remarkable photo-synaptic behavior in the field of rare earth ion-doped luminescent oxides by using long-persistent luminescence (LPL). This system utilizes electron trap states to regulate the synaptic behavior, operating through a fundamentally different mechanism from that of electronic-based synaptic devices. To realize this strategy, Tb Show less