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Videoconferencing Delivery of the Seoul Premarital Education Program During COVID-19: A Quasi-experimental Study Using Inverse Probability of Treatment Weighting
This study examined whether the Seoul Premarital Education Program (S-PEP) was effective when it was delivered via videoconferencing (VC) during the early COVID-19 period. S-PEP is a city-wide educational program designed to prevent marital distress by enhancing premarital readiness and relationship quality for couples. Because a randomized controlled trial was not realistic due to the pandemic, we recruited an intervention group and a no-intervention comparison group independently, who completed both the pre- and posttests. We then employed inverse probability of treatment weighting to derive two comparable groups. The weighted samples of 291 women and 228 men were analyzed separately using linear mixed models. The results showed that S-PEP via VC was effective in increasing levels of marital readiness for both women and men and in enhancing relationship confidence and satisfaction for women. Our findings suggest that VC can be a promising delivery strategy for curriculum-based group interventions for couples.Y
Impaired chaperone-mediated autophagy leads to abnormal SORT1 (sortilin 1) turnover and CES1-dependent triglyceride hydrolysis
SORT1 (sortilin 1), a member of the the Vps10 (vacuolar protein sorting 10) family, is involved in hepatic lipid metabolism by regulating very low-density lipoprotein (VLDL) secretion and facilitating the lysosomal degradation of CES1 (carboxylesterase 1), crucial for triglyceride (TG) breakdown in the liver. This study explores whether SORT1 is targeted for degradation by chaperone-mediated autophagy (CMA), a selective protein degradation pathway that directs proteins containing KFERQ-like motifs to lysosomes via LAMP2A (lysosomal-associated membrane protein 2A). Silencing LAMP2A or HSPA8/Hsc70 with siRNA increased cytosolic SORT1 protein levels. Leupeptin treatment induced lysosomal accumulation of SORT1, unaffected by siLAMP2A co-treatment, indicating CMA-dependent degradation. Human SORT1 contains five KFERQ-like motifs (658VVTKQ662, 730VREVK734, 733VKDLK737, 734KDLKK738, and 735DLKKK739), crucial for HSPA8 recognition; mutating any single amino acid within these motifs decreased HSPA8 binding. Furthermore, compromised CMA activity resulted in elevated SORT1-mediated degradation of CES1, contributing to increased lipid accumulation in hepatocytes. Consistent with in vitro findings, LAMP2A knockdown in mice exacerbated high-fructose diet-induced fatty liver, marked by increased SORT1 and decreased CES1 levels. Conversely, LAMP2A overexpression promoted SORT1 degradation and CES1D accumulation, counteracting fasting-induced CES1D suppression through CMA activation. Our findings reveal that SORT1 is a substrate of CMA, highlighting its crucial role in directing CES1 to lysosomes. Consequently, disrupting CMA-mediated SORT1 degradation significantly affects CES1-dependent TG hydrolysis, thereby affecting hepatic lipid homeostasis.Abbreviations: APOB: apolipoprotein B; CES1: carboxylesterase 1; CMA: chaperone-mediated autophagy; HSPA8/Hsc70: heat shock protein family A (Hsp70) member 8; LAMP2A: lysosomal associated membrane protein 2A; LDL-C: low-density lipoprotein-cholesterol; PLIN: perilipin; SORT1: sortilin 1; TG: triglyceride; VLDL: very low-density lipoprotein; Vps10: vacuolar protein sorting 10.N
Measurements of the quantum geometric tensor in solids
Understanding the geometric properties of quantum states and their implications in fundamental physical phenomena is a core aspect of contemporary physics. The quantum geometric tensor (QGT) is a central physical object in this regard, encoding complete information about the geometry of the quantum state. The imaginary part of the QGT is the well-known Berry curvature, which plays an integral role in the topological magnetoelectric and optoelectronic phenomena. The real part of the QGT is the quantum metric, whose importance has come to prominence recently, giving rise to a new set of quantum geometric phenomena such as anomalous Landau levels, flat band superfluidity, excitonic Lamb shifts and nonlinear Hall effect. Despite the central importance of the QGT, its experimental measurements have been restricted only to artificial two-level systems. Here, we develop a framework to measure the QGT in crystalline solids using polarization-, spin- and angle-resolved photoemission spectroscopy. Using this framework, we demonstrate the effective reconstruction of the QGT in the kagome metal CoSn, which hosts topological flat bands. Establishing this momentum- and energy-resolved spectroscopic probe of the QGT is poised to significantly advance our understanding of quantum geometric responses in a wide range of crystalline systems. Experiments that directly probe the quantum geometric tensor in solids have not been reported. Now, the quantum metric and spin Berry curvature-dual components of the quantum geometric tensor-have been simultaneously measured in reciprocal space.N
금융데이터분석
2024년 2학기 서울대학교 데이터사이언스대학원에서 강의한 금융데이터분석 (Financial Data Analysis) 과목의 강의 슬라이드를 모아서 출간한 것 (DATAlyLab Lecture Note Series
Commensurate, Incommensurate, and Reconstructed Structures of Multilayer Transition Metal Dichalcogenide and Their Applications
Multilayer transition metal dichalcogenides (ML-TMDs) with commensurate, incommensurate, and reconstructed structures, have emerged as a class of 2D materials with unique properties that differ significantly from their monolayer counterparts. While previous research has focused on monolayers, the discovery of various novel properties has sparked interest in multilayers with diverse structures engineered through stacking. These materials are characterized by interactions between layers and exhibit remarkable tunability in their structural, optical, and electronic behaviors depending on stacking order, twist angle, and interlayer coupling. This review provides an overview of ML-TMDs and explores their properties such as electronic band structure, optical responses, ferroelectricity, and anomalous Hall effect. Various synthetic methods employed to fabricate ML-TMDs, including mechanical stacking and chemical vapor deposition techniques, with an emphasis on achieving precise control of the twist angles and layer configurations, are discussed. This study further explores potential applications of ML-TMDs in nanoelectronics, optoelectronics, and quantum devices, where their unique properties can be harnessed for next-generation technologies. The critical role played by these materials in the development of future electronic and quantum devices is highlighted.N
Secreted LGALS3BP facilitates distant metastasis of breast cancer
BackgroundPatients with estrogen receptor (ER)-positive breast cancer (BC) can be treated with endocrine therapy targeting ER, however, metastatic recurrence occurs in 25% of the patients who have initially been treated. Secreted proteins from tumors play important roles in cancer metastasis but previous methods for isolating secretory proteins had limitations in identifying novel targets.MethodsWe applied an in situ secretory protein labeling technique using TurboID to analyze secretome from tamoxifen-resistant (TAMR) BC. The increased expression of LGALS3BP was validated using western blotting, qPCR, ELISA, and IF. Chromatin immunoprecipitation was applied to analyze estrogen-dependent regulation of LGALS3BP transcription. The adhesive and angiogenic functions of LGALS3BP were evaluated by abrogating LGALS3BP expression using either shRNA-mediated knockdown or a neutralizing antibody. Xenograft mouse experiments were employed to assess the in vivo metastatic potential of TAMR cells and the LGALS3BP protein. Clinical evaluation of LGALS3BP risk was carried out with refractory clinical specimens from tamoxifen-treated ER-positive BC patients and publicly available databases.ResultsTAMR secretome analysis revealed that 176 proteins were secreted at least 2-fold more from MCF7/TAMR cells than from sensitive cells, and biological processes such as cell adhesion and angiogenesis were associated with the TAMR secretome. Galectin-3 binding protein (LGALS3BP) was one of the top 10 most highly secreted proteins in the TAMR secretome. The expression level of LGALS3BP was suppressed by estrogen signaling, which involves direct ER alpha binding to its promoter region. Secreted LGALS3BP in the TAMR secretome helped BC cells adhere to the extracellular matrix and promoted the tube formation of human umbilical vein endothelial cells. Compared with sensitive cells, xenograft animal experiments with MCF7/TAMR cells showed increased pulmonary metastasis, which completely disappeared in LGALS3BP-knockdown TAMR cells. Finally, higher levels of LGALS3BP were associated with poor prognosis in ER-positive BC patients treated with adjuvant tamoxifen in the clinic.ConclusionTAMR secretome analysis identified secretory proteins, such as LGALS3BP, that are involved in biological processes closely related to metastasis. Secreted LGALS3BP from the TAMR cells promoted adhesion of the cells to the extracellular matrix and vasculature formation, which may support metastasis of TAMR cells.Y
Synergistic effect of naringenin and mild heat for inactivation of E. coli O157:H7, S. Typhimurium, L. monocytogenes, and S. aureus in peptone water and cold brew coffee
This study aimed to investigate the bactericidal effect of naringenin (NG), a plant-derived flavonoid, and its synergistic effect with mild heat (MH) treatment at 50 °C in peptone water (PW) and ready-to-drink cold brew coffee (RDC). Among various NG concentrations (1–20 mM), 10 mM NG resulted in the greatest inactivation for Escherichia coli O157:H7, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus. In RDC, NG + MH treatment resulted in a 5–8-log reduction in all pathogens after 10 min, except for S. aureus. In contrast, NG or MH treatment alone exhibited only marginal bactericidal effects. From inactivating mechanism analysis, lipid membrane destruction and intracellular enzyme inactivation were the key factors for pathogen inactivation. Cell membrane and enzyme dysfunctions were identified in propidium iodide (PI) uptake test, membrane potential assay, and membrane protein analysis. Furthermore, NG + MH exerted minimal influence on the quality attributes of RDC in pH, color, and total phenolic content. These results indicated that the NG + MH treatment system effectively ensured microbial safety in cold brew coffee while enhancing its nutritional value and preserving quality attributes.N
Advanced spectroscopic evidence for the sequestration of heavy metals via repetitive in situ synthesis of Fe oxide
The in situ synthesis of Fe oxide is an established method for stabilizing metals and metalloids (Me) in contaminated soils. Nevertheless, the potential for enhanced Me sequestration through repeated Fe oxide application and the fundamental mechanisms of this process yet to be systemically investigated. In this study, the means by which repetitive Fe oxide synthesis enhances the immobilization of Cd, Zn, and As was investigated using batch experiments. The first synthesis resulted in surface-adsorbed Cd, Zn, and As levels of 68.7, 37.5, and 22.6 %, respectively. The second synthesis reduced the surface-adsorbed Cd and Zn levels to 53.9 % and 23.3 %, respectively, while the As level remained unchanged (22.8 %) owing to its structural incorporation and the occurrence of OH− induced desorption/re-adsorption. The third synthesis further decreased the surface-adsorbed metal levels, surpassing the reduction achieved by a single synthesis with an increased Fe content. Extended X-ray absorption fine structure analysis revealed peak shifts in the Me K-edge-fitted spectra, distinguishing incorporated metals from surface-adsorbed metals. In addition, energy dispersive X-ray spectroscopy revealed decreased heavy-metal concentrations on the surfaces and cross-sections of the repeatedly synthesized Fe oxide particles, indicating encapsulation by the hydrolyzed Fe species. While conventional methods rely on single applications, repetitive Fe oxide synthesis non-specifically sequesters surface-adsorbed metals through encapsulation. This repetitive approach achieved the enhanced immobilization of weakly adsorbed metals, rendering it potentially effective in soils exhibiting different properties, and indicating its possibility for use as a viable remediation strategy.N
Greater Influence of Density on the Electrical Properties of an Organic Semiconductor Glass Compared to Molecular Orientation
Physical vapor deposition is widely used in the fabrication of organic light-emitting diodes and has the potential to adjust the density and orientation through substrate temperature control, which may lead to enhanced electrical performance. However, it is unclear whether this enhanced property is because of the horizontal molecular orientation or the increased density. The effects of the density and orientation on the electrical properties of a potential electron transport material, (3-dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide (TPPO-dibenzacridine), were investigated. According to the gyration tensor analysis, TPPO-dibenzacridine resembled an oblate ellipsoid. Furthermore, these films exhibited the highest density when prepared at a substrate temperature of 87.5% of the glass transition temperature with an increase in density of approximately 1.5%. Variable angle spectroscopic ellipsometry measurements confirmed that the transition dipole moment direction of the dibenzacridine moiety, which is involved in the electrical properties, remained isotropic at this temperature. Although horizontal orientations are known to optimize their pi-pi overlap and improve the electrical properties, the lowest driving voltage was observed under these conditions, which led to the conclusion that the enhanced electrical properties of TPPO-dibenzacridine are greatly influenced by the increased density rather than by the molecular orientation.N
Text Motion Translator: A Bi-directional Model for Enhanced 3D Human Motion Generation from Open-Vocabulary Descriptions
The field of 3D human motion generation from natural language descriptions, known as Text2Motion, has gained significant attention for its potential application in industries such as film, gaming, and AR/VR. To tackle a key challenge in Text2Motion, the deficiency of 3D human motions and their corresponding textual descriptions, we built a novel large-scale 3D human motion dataset, LaViMo, extracted from in-the-wild web videos and action recognition datasets. LaViMo is approximately 3.3 times larger and encompasses a much broader range of actions than the largest available 3D motion dataset. We then introduce a novel multi-task framework TMT (Text Motion Translator), aimed at generating faithful 3D human motions from natural language descriptions, especially focusing on complicated actions and those not existing in the training set. In contrast to prior works, TMT is uniquely regularized by multiple tasks, including Text2Motion, Motion2Text, Text2Text, and Motion2Motion. This multi-task regularization significantly bolsters the models robustness and enhances its ability of motion modeling and semantic understanding. Additionally, we devised an augmentation method for the textual descriptions using Large Language Models. This augmentation significantly enhances the models capability to interpret open-vocabulary descriptions while generating motions. The results demonstrate substantial improvements over existing state-of-the-art methods, particularly in handling diverse and novel motion descriptions, laying a strong foundation for future research in the field.N