https://scholar.dgist.ac.kr/handle/20.500.11750/133 2026-10-03T21:37:09Z https://scholar.dgist.ac.kr/handle/20.500.11750/60905 Title: Translational Profiling of Drd2-Expressing Populations Reveals Molecular Heterogeneity of Dentate Gyrus Mossy Cells along the Dorsoventral Axis Author(s): Jeong, Minseok; Jang, Jin-Hyeok; Oh, Seo-Jin; Choi, Ji-Woong; Oh, Yong-Seok Abstract: Hilar mossy cells (MCs) are crucial for integrating and propagating signals across the hippocampal dorsoventral axis, mediating cognitive and affective processing. While MCs exhibit profound dorsoventral differences in their projections, physiology, and behavioral roles, the molecular basis underlying this functional specialization remains largely unexplored. To address this gap, we used translating ribosome affinity purification (TRAP) in male mice to systematically compare the translatome of Drd2-expressing, MC-enriched populations along the dorsoventral axis. This analysis revealed distinct translational signatures with 1,442 genes enriched in dorsal and 1,337 genes in ventral Drd2-expressing, MC-enriched populations. Pathway analysis demonstrated significant functional segregation along the dorsoventral axis. The dorsal population is notably enriched for genes linked to neuronal connectivity and synaptic transmission, whereas the ventral counterpart shows enrichment in genes associated with energy metabolism and cellular maintenance. Specifically, we identified a subset of dorsal enriched genes, including neurotransmitter receptors, ion channels, and axon guidance regulators, contrasting with ventral enriched genes highly related to glucose/fatty acid metabolism, oxidative phosphorylation, and exocytosis. We further predicted distinct sets of upstream transcriptional regulators activated in each subpopulation, providing insights into the regulatory networks that may drive molecular divergence. Our findings provide a translatomic basis for the dorsoventral heterogeneity of Drd2-expressing neurons that include MCs, offering molecular signatures associated with their differential contributions to hippocampal function. 2026-06-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60623 Title: Iterative Joint Detection and ORBGRAND for Massive Multi-User MIMO Author(s): Park, Hanyoung; Choi, Ji-Woong Abstract: Multi-user multi-input multi-output (MU-MIMO) is a key enabler for next-generation wireless systems, but its performance is often limited by strong interference from inter-user channel correlations and the lack of decoding-aware detection strategies. To address this challenge, we propose a joint iterative detection and decoding algorithm that consists of detection, ordered reliability bits guessing random additive noise decoding (ORBGRAND), and hard/soft parallel interference cancellation (PIC) switching, in consideration of inter-user channel correlation and decoding failure. Simulation results demonstrate that the proposed scheme outperforms state-of-the-art baselines, providing a significantly improved block error rate (BLER). These results highlight the potential of the proposed method as an efficient and robust solution for coded MU-MIMO systems. 2025-12-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59380 Title: Short-term memory errors are strongly associated with a drift in neural activity in the posterior parietal cortex Author(s): Choi, Joon Ho; Bae, Sungwon; Park, Jiho; Yoo, Minsu; Kim, Chul Hoon; Schmitt, Lukas Ian; Tchoe, Youngbin; Chung, Dongil; Choi, Ji-Woong; Rah, Jong-Cheol Abstract: Understanding the neural mechanisms behind short-term memory (STM) errors is crucial for unraveling cognitive processes and addressing deficits associated with neuropsychiatric disorders. This study examines whether STM errors arise from misrepresentation of sensory information or decay in these representations over time. Using 2-photon calcium imaging in the posterior parietal cortex (PPC) of mice performing a delayed match-to-sample task, we identified a subset of PPC neurons exhibiting both directional and temporal selectivity. Contrary to the hypothesis that STM errors primarily stem from mis-encoding during the sample phase, our findings reveal that these errors are more strongly associated with a drift in neural activity during the delay period. This drift leads to a gradual divergence away from the correct representation, ultimately leading to incorrect behavioral responses. These results emphasize the importance of maintaining stable neural representations in the PPC for accurate STM. Furthermore, they highlight the potential for therapeutic interventions aimed at stabilizing PPC activity during delay periods as a strategy for mitigating cognitive impairments in conditions like schizophrenia. 2025-08-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59222 Title: Stable olfactory receptor activation across odor complexity Author(s): Kim, Minseok; Lee, Jeongyoon; Park, Inah; Kim, Jihoon; Lee, Keunsoon; So, Jinhyun; Choi, Ji-Woong; Jang, Jae Eun; Kwon, Hyuk-Jun; Moon, Cheil; Choe, Han Kyoung Abstract: Mechanisms underlying single odorant activation of specific olfactory receptors are well understood. However, how the olfactory system processes complex odor mixtures at the receptor level remains unclear. This study examined olfactory receptor activation patterns across odor complexities using phosphoTRAP analysis. For most mixtures, receptor activation patterns closely matched the linear sum of individual component responses. However, distinct receptor sets display non-linear responses unexplained by linear models. Mixture responses were generally located between component responses and often aligned with linear predictions, though some deviations indicated non-linear interactions. Total activated receptors remained relatively constant regardless of odor complexity, suggesting efficient coding that prevented receptor saturation as odorant components increased. These findings provide receptor-level evidence that the olfactory system encodes complex odors primarily through linear integration of receptor activity, with added specificity from non-linear responses in limited receptors, advancing understanding of how the olfactory system normalizes receptor activation in response to natural odors. 2025-10-31T15:00:00Z