Lutetium Texaphyrin-Celecoxib Conjugate as a Potential Immuno-Photodynamic Therapy Agent
Chemistry LEE, JINYONG Prof. · Ph. D. Jong Hyeon Lim
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Lutetium Texaphyrin-Celecoxib Conjugate as a Potential Immuno-Photodynamic Therapy Agent
The research team led by Prof. Jin Yong Lee of the Department of Chemistry (co-first author Ph. D. Jong Hyeon Lim) has developed a new lutetium texaphyrin photosensitizer (PS) system, LuCXB for Immuno-photodynamic therapy (IPDT) through collaborative research with research teams led by Prof. Dixian Luo (Huazhong University of Science and Technology Union Shenzhen Hospital), Prof. Quan Liu (Huazhong University of Science and Technology Union Shenzhen Hospital), Jonathan L. Sessler (University of Texas), and Prof. Jong Seung Kim (Korea University). The research was published in Journal of the American Chemical Society (IF: 14.4) in July 2024 under the title "Lutetium Texaphyrin-Celecoxib Conjugate as a Potential Immuno-Photodynamic Therapy Agent." Conventional photodynamic therapy (PDT) is a promising non-invasive treatment for cancer; however, it has shown limitations such as reduced therapeutic efficiency due to hypoxia around cancer cells, inhibition of reactive oxygen species (ROS) generation, and failure to completely remove tumors or prevent recurrence and metastasis. This study addresses these limitations by exploring methods to enhance PDT efficacy through the conversion of ROS generation mechanisms and integrating immunotherapy to prevent cancer recurrence. The LuCXB system developed in this study utilizes the Lutetium texaphyrin structure, which selectively accumulates in tumor tissues, allowing it to effectively target the cancer cells. By interacting with the Celecoxib structure in an aqueous environment, the system shifts ROS generation from the type II mechanism to the type I mechanism, thereby enhancing ROS generation efficiency even in hypoxic conditions. Professor Lee's team used non-adiabatic molecular dynamics (NAMD) simulations and density functional theory (DFT) calculations to elucidate the folding structure and corresponding energy state changes in an aqueous environment, providing theoretical insights into the ROS generation mechanism shift. They also confirmed differences in ROS generation efficiency from a kinetic perspective when compared to reference systems. The newly developed photosensitizer in this study is expected to contribute to the advancement of photodynamic therapy for cancer treatment. *Title:Lutetium Texaphyrin-Celecoxib Conjugate as a Potential Immuno-Photodynamic Therapy Agent.
- No. 266
- 2024-10-08
- 114
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Prof. Lee "Non-clinical interactions with staff lead to higher impact on patient satisfaction than clinical interactions
Prof. Lee, with a co-author Richard Staelin (Duke University's Fuqua School of Business), analyzed a set of 317 thousand Google reviews of U.S. acute care hospitals. The output of these analyses shows that non-clinical factors, such as kind doctors and staff and clean facilities, have roughly twice the impact on patient satisfaction compared to clinical factors, like diagnosis and treatment outcomes. Evaluation of each factor was independent from each other and often patients had ‘mixed’ evaluation where some factors were positively evaluated while others were negatively evaluated. Furthermore, patients did not evaluate hospital services by separating specific staffs (doctors, nurses, or other employees), or different departments (ER, surgery, billing, etc.). Instead, patients assessed their satisfaction based on their overall perception of the service received from the entire team of staffs providing the hospital care. These findings have important implications for understanding the voice of the customers for hospitals and other businesses. While clinical factors are important for increasing patient satisfaction, non-clinical factors are also crucial, so hospitals should make strategic decisions on which aspects to invest in depending on the feedback received from the patients. The methodology used in this paper can serve as a simple roadmap for analyzing the massive amount of online customer feedback, which can help firms better understand their customer satisfaction and address areas that need improvement. Journal: https://doi.org/10.1007/s11002-024-09738-2
- No. 265
- 2024-09-30
- 234
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SAINT faculty Prof. Seongpil An research team, developed a flexible lithium ion battery with high-energy/-power density
Sungkyunkwan University (President Jibeom Yoo) and a research team led by Prof. Seongpil An from the SKKU Advanced Institute of Nanotechnology (SAINT) has recently developed a flexible lithium-ion battery with high energy density (208 Wh kg-1) and high power density (1,048 W kg-1), based on a three-dimensional (3D) percolative metal microweb structure. This breakthrough offers promising applications in a wide range of flexible devices and a power source for electric vehicles. Flexible batteries are a cornerstone technology for wearable electronics, capable of maintaining electrochemical performance under physical deformation. However, existing commercial lithium-ion batteries face safety issues, such as short circuits and potential explosions when subjected to mechanical deformation. To address these challenges and enhance both flexibility and energy density, prior studies have focused on the development of 3D electrode architectures. Nevertheless, conventional electrode coating methods have struggled to preserve their structures, thus limiting their performance benefits. In this study, the research teams have fabricated an ultra-lightweight flexible current collector based on a 3D percolative metal microweb via electrospinning and electroplating techniques. Furthermore, 3D electrode structure-based flexible lithium-ion battery with enhanced energy and power densities has been developed by employing electrostatic spray coating technology. Through two-dimensional modeling and electrochemical characterization, they identified significant enhancements in lithium-ion diffusion and electron transfer rate within this structure. Additionally, by incorporating a polymer gel electrolyte, they have developed a flexible all-solid-state lithium-ion battery that maintained operational stability even under mechanical deformation and cutting, demonstrating exceptional robustness. These advancements are expected to applicable to wide array of cutting-edge devices, including virtual and augmented reality, the metaverse, healthcare, and medical devices. ※ Traditional Electrode Coating Process: Slot die coating, a technique used to apply solutions, slurries, hot melt, or extruded thin films onto flat substrates. ※ Electrospinning: A fiber production method that uses electric force to draw charged threads of polymer solutions or polymer melts up to fiber diameters in the order of some hundred nanometers. ※ Electrostatic spraying: A voltage-driven process governed by the electrohydrodynamic phenomena where particles are made from a polymer solution. Prof. An's research team (1st author, research professor Dr. Hongseok Jo) developed a flexible electrode based on 3D percolative metal microweb to address the inherent limitations of flexibility and energy density in conventional two-dimensional (2D) flat electrodes. This novel 3D microweb structure is more than four times lighter than traditional two-dimensional electrodes and exhibited remarkable mechanical durability, with less than a 2% change in electrical properties after more than 3,000 cycles of mechanical deformation. The 3D architecture significantly increased the surface area in contact with the electrolyte and reduced electron transfer distances, l resulting in over six-fold and four-fold improvements in lithium-ion diffusion and electron mobility, respectively, compared to conventional 2D structures. This is verified through 2D modeling and electrochemical analysis. This led to the realization of a flexible lithium-ion battery with energy density (208 Wh kg-1) and power density (1,048 W kg-1) that exceeds the performance of existing commercial lithium-ion batteries by more than double. Additionally, the all-solid-state flexible lithium-ion battery, utilizing a polymer gel electrolyte, maintained stable voltage even after undergoing significant mechanical deformations, such as bending and cutting, thereby ensuring both safety and operational stability. This research provides a significant breakthrough in the development of next-generation flexible electronic devices, offering a crucial solution to the limitations of existing battery technologies. Prof. An, the corresponding author of this study, stated, “Recently, research and development in battery system architecture have been actively pursued. Therefore, innovative advancements in battery architecture must continue in the future through active knowledge exchange between researchers across various fields.” Lastly, the 1st author of this study, research professor Hongseok Jo, expressed his intention, “These 3D percolative metal microweb-based flexible electrode exhibits ultra-lightweight and high specific area, which significant contribute to improved energy- and power-densities. The unique architecture is also expected to effectively dissipate heat generated during electrochemical reactions. I believed that this approach offers a promising solution to address recent concerns related to overheating and the risk of explosion in lithium ion batteris.” I believed that this approach offers a promising solution to address recent concerns related to overheating and the risk of explosion in lithium ion batteris.” This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) RS-2023-00211303, RS-2023-00247975, and 2022M3H4A408507611. This study was published on Aug. 13th in Advanced Materials (IF: 27.4), one of the world-renowned academic journals in the top 2.2% of the material science field. ※ Title : Percolative Metal Microweb-Based Flexible Lithium-Ion Battery with Fast Charging and High Energy Density (Journal: Advanced Materials, https://onlinelibrary.wiley.com/doi/full/10.1002/adma.202407719) ▲ Schematic of fabrication process of high-energy/-power density flexible lithium-ion batteries based on 3D percolative metal microweb, and the properties of the developed electrode ▲ Half-cell performance results of 3D electrodes, including electrochemical and simulated analysis, including C-rate performance, cycling test, lithium ion diffusion, electron transfer, and overpotential ▲ Performance of 3D electrode-based full cell and polyer gel electrolyte-based all-solid-state flexible lithium ion battery.
- No. 264
- 2024-09-23
- 369
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Professor Kwon revealed that government research support has been significantly undercredited in patents
According to research by Professor Seokbeom Kwon from the Department of Systems Management Engineering, the contribution of government research support to patented technologies has been underestimated. The study reveals that the higher the private stakes in the exclusive use of a research outcome are, the more likely it is that government research support is not credited in the resulting patents. This research was published as a solo-authored paper by Professor Kwon in Science on August 30. The government has implemented various policy measures, including research funding, provision of technological infrastructure, and personnel support, to promote basic science and technological innovation therefrom. Research outcomes derived from this support can lead to patents, and the government requires that such patents explicitly acknowledge its support by law. This requirement is a regulatory mechanism designed to ensure that the government retains the right to utilize the patent to serve the public interest. However, the study shows that patents frequently failed to comply with this rule. Analyzing about 84,000 U.S. patents and corresponding research papers, Professor Kwon found that approximately 30% of the patents on government-sponsored research failed to disclose government research supports. This omission was particularly prevalent in patents with significant private stakes involved. For example, when a company owned the patent or when both the company and the government provided funding, the more valuable the technology or its economic potential, the more frequently the government support acknowledgment was omitted. Professor Kwon suggests that these findings indicate the government’s contribution to technological innovation may have been underestimated. When government support is not properly acknowledged, it not only underestimates the government’s role in scientific and technological advancements but also constrains the government’s ability to exercise its rights to use the patent for public benefit. Professor Kwon stated, “Acknowledging government research support in patents is a crucial institutional instrument that ensures the government can utilize the research outcomes for the public good. This study is expected to serve as evidence supporting the need for a systematic monitoring and relevant enforcement mechanism to ensure proper acknowledgment of government support in patents.” ※ Paper: Underappreciated government research support in patents ※ Journal: Science ※ DOI: www.science.org/doi/10.1126/science.ado1078 ▲ Comparison of likelihood of acknowledging US government research support in patents ▲ Comparison of Economic and Technical Value of Patents
- No. 263
- 2024-09-20
- 234
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Investigates the Efficiency of Korean Language Use
Professor Hanjung Lee from the Department of English Language and Literature at Sungkyunkwan University is set to publish a research paper in 『Language』, one of the most prestigious international journals in the field of linguistics. This paper, scheduled for publication in September, marks the first time a Korean linguist has published a sole-author paper in this journal (excluding brief articles and review papers). 『Language』, published by the Linguistic Society of America, celebrates its 100th anniversary this year, making this achievement even more significant. Professor Lee's paper, titled “Cues Reliability, Communication Efficiency, and Differential Subject Marking: Evidence from Korean,” is an in-depth exploration of the principles of communication efficiency in language use. The study analyzes how Korean speakers adjust the complexity of noun phrases in informal conversations based on the reliability of contextual cues, identifying ways to optimize the balance between cognitive cost in language production and communication effectiveness. In this research, Professor Lee conducted a meticulous analysis of Korean conversational data, examining the impact of linguistic and non-linguistic factors on the complexity of subject noun phrases. She stated, "This study provides a deeper understanding of the unique linguistic features of Korean,” and added, "By elucidating the principles of efficiency in language use, we aim to show how sophisticated human communication systems are.” The research was supported by the National Research Foundation of Korea, through which Professor Lee aimed to offer new insights into the universal principles operating behind the unique structure and use of the Korean language. Professor Hanjung Lee runs the 'Language Cognition Lab' at Sungkyunkwan University's Department of English Language and Literature, where Professor Nayoun Kim and both undergraduate and graduate students participate in producing international research on language structure, meaning, and cognition. Additionally, with support from the university's AI Convergence College Innovation Project, she focuses on developing AI-based English research and teaching methodologies.
- No. 262
- 2024-09-10
- 471
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Development of Highly Efficient and Moisture-Stable Perovskite Solar Cells
A collaborative research team led by Prof. Hyun Suk Jung from the Department of Advanced Materials & Science Engineering and the SKKU Insititute of Energy Science and Technology(SIEST) has successfully developed highly efficient and stable perovskite solar cells by utilizing perovskite-polymer composites. Halide perovskite thin films often experience lattice distortion during crystal growth due to mismatches in the thermal expansion coefficients with the substrate, leading to residual stress within the film. This stress lowers the activation energy for ion migration, accelerating perovskite decomposition, which necessitates the development of related technologies to ensure stability. Additionally, halide perovskite materials are extremely vulnerable to moisture, making moisture stability a critical requirement for commercialization. To address these challenges, Prof. Hyun Suk Jung’s research team has developed an innovative approach to overcome the instability of perovskite, which has been a major obstacle to the commercialization of high-efficiency solar cells. The research team produced stable and high-efficiency perovskite solar cells by cross-linking amorphous perovskite films with acrylamide monomers through light irradiation. This method promotes crystal growth and cross-linking between crystals within the film, significantly enhancing the stability of the perovskite thin films. Notably, acrylamide monomers expand the grain size of the perovskite films, induce preferred crystal orientation, and the cross-linked layer protects the perovskite films from moisture-induced degradation. The research team highlighted that the technology developed through this research not only improves the efficiency of perovskite solar cells but also achieves significant advances in long-term stability. According to the study, the device fabricated using the proposed strategy achieved a power conversion efficiency (PCE) of 24.45% and an open-circuit voltage (VOC) of 1.199 V, the highest VOC reported in the field of halide perovskite solar cells with a TiO2 electron transport layer. The device also demonstrated high stability in humid environments, retaining 80% of its initial performance after 700 hours, and excellent photostability, maintaining 80% of its initial performance after 1,008 hours. Process of the control in crystal growth in perovskite films to produce high-quality films and of enhancement of the hydrophobic properties of the films Additionally, the research team successfully fabricated a large-area PSC module using the proposed strategy. This module, with an active area of 33 cm², exhibited a high fill factor of 77.1%, a power conversion efficiency of 20.31%, and outstanding storage stability, demonstrating its potential for scaling up to large-area devices. This research is of academic significance as it effectively addresses the issues of grain boundary defects and lattice distortion in halide perovskite thin films, thereby enhancing their commercialization potential. Prof. Hyun Suk Jung explained, "This novel approach using acrylamide monomers can mitigate lattice distortion, control crystal growth in perovskite films to produce high-quality films, and enhance the hydrophobic properties of the films, thereby addressing the long-standing issue of moisture stability in halide perovskite materials. This technology holds promise for contributing to commercialization." The research findings were published as a cover article in the top 3% international journal in the Energy and Fuels field, Advanced Energy Materials, on January 5, 2024. ※ Journal: Advanced Energy Materials ※ Title: In Situ Polymerization of Cross-Linked Perovskite–Polymer Composites for Highly Stable and Efficient Perovskite Solar Cells ※ DOI: 10.1002/aenm.202302743 ※ Author list - Corresponding Authors: Prof. Hyun-Seok Jung (Department of Advanced Materials & Science Engineering, Sungkyunkwan University / SKKU Institute of Energy Science and Technology(SIEST)), Gil-Sang Han (Korea Research Institute of Chemical Technology) - First Author: Guo He (Ph.D. candidate, Department of Advanced Materials & Science Engineering, Sungkyunkwan University) - Co-authors: Geon Woo Yoon (Ph.D. candidate, Advanced Materials & Science Engineering, Sungkyunkwan University), Zi Jia Li (China New Energy R&D Center), Dr. Yeonghun Yun, Prof. Sangwook Lee (Department of Materials Science and Engineering, Kyungpook National University), Dr. You-Hyun Seo, Senior Researcher Nam Joong Jeon (Korea Research Institute of Chemical Technology)
- No. 261
- 2024-09-04
- 351
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The finding that the use of GLP-1RAs was not associated with an increased risk of thyroid cancer
A research team led by Professor Ju-Young Shin from the School of Pharmacy has found that glucagon-like peptide-1 receptor agonists (GLP-1RAs) and dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) are not associated with the risk of thyroid cancer in patients with type 2 diabetes. “Incretin-based therapies, including GLP-1RAs and DPP-4 inhibitors are commonly included in combination therapies to achieve glycaemic goals, reduce body weight, minimize weight gain, or prevent cardiorenal events in patients with type 2 diabetes. However, issues related to the increased risk of thyroid cancer with incretin-based therapies have not yet been settled.”, said Professor Shin. Using nationwide healthcare insurance data of South Korea from 2014 to 2020, two distinct cohorts were established to compare each drug with sodium-glucose cotransporter-2 (SGLT2) inhibitors, chosen as active comparators because of their previous non-association with thyroid cancer. Weighted Cox proportional models were used to estimate hazard ratios of thyroid cancer incidence associated with incretin-based drugs of interest. The team found that the use of GLP-1RAs was not associated with an increased risk of thyroid cancer (weighted hazard ratio 0.98, 95% confidence interval 0.62-1.53) compared with that of SGLT2 inhibitors. Using DPP-4 inhibitors was also not associated with an increased risk of thyroid cancer (0.95, 0.79-1.14) compared with that of SGLT2 inhibitors. "These findings provide insights that the use of GLP-1RAs and DPP-4 inhibitors do not increase the risk of thyroid cancer in patients with type 2 diabetes. Therefore, when considering the risk-benefit balance of incretin-based drugs in patients with type 2 diabetes, the potential for an elevated risk of thyroid cancer would be negligible.", concluded Dr Shin. The study was co-led by Professor Ju-Young Shin (School of Pharmacy, Sungkyunkwan University), and Professor Young Min Cho (Division of Endocrinology, Department of Internal Medicine, Seoul National University Hospital), with Professor HeeJun Son (Division of Endocrinology, Department of Internal Medicine, Seoul National University Hospital) as co-first authors, and Professor Jae Hyun Bae (Department of Internal Medicine, Korea University Anam Hospital, Korea University College of Medicine), and Sun Wook Cho (Division of Endocrinology, Department of Internal Medicine, Seoul National University Hospital) as co-investigators.
- No. 260
- 2024-08-29
- 531
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Results of a study analyzing the impact of interpersonal conflict at work and religious struggles on workers' well-being
Professor Jong Hyun Jung’s research team in the Department of Sociology at Sungkyunkwan University announced the results of a study analyzing the impact of interpersonal conflict at work and religious struggles on workers' well-being. This study was based on a large-scale survey of Singaporean workers and examined whether religious struggles play a role in moderating the relationship between workplace interpersonal conflict and employee well-being. Professor Jung said, “Interpersonal conflict at work is a critical factor in job stress, which can increase workers’ psychological distress and reduce job satisfaction. This study sought to assess whether and how religious struggles amplify or weaken the negative effects of workplace interpersonal conflict on worker well-being.” The research team collected information from 508 adult workers aged 20 and older in Singapore from 2021 to 2022. The survey was conducted in English and Chinese, and some of the key measures included psychological distress, job satisfaction, interpersonal conflict at work, and religious struggles. Religious struggles consisted of items measuring negative feelings or thoughts about God. This study provides important evidence that religious struggles can modify the impact of workplace interpersonal conflict on workers' psychological distress and job satisfaction. Professor Jung added, “Workers with high levels of religious struggles may be more negatively affected by interpersonal conflict at work, which means that religious beliefs may play a pivotal role in shaping worker well-being.” Professor Jung from the Department of Sociology at Sungkyunkwan University led this research, and other scholars such as Joy Soo and Shannon Ang from Nanyang Technological University participated as co-authors.
- No. 259
- 2024-08-21
- 435
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Research on Pairs Trading via Unsupervised Learning
Professor Chulwoo Han from Sungkyunkwan University recently published innovative research on pairs trading using unsupervised learning. Pairs trading is a market-neutral investment strategy that buys an undervalued stock and sells an overvalued stock when two stocks with similar characteristics diverges from each other. This study aims to significantly improve traditional pairs trading strategies to achieve higher returns and expand their applicability in financial markets. Professor Han has made significant contributions to the burgeoning field of financial research utilizing machine learning. While most existing studies rely on supervised learning, Professor Han explored pairs trading strategies using unsupervised learning in this study. Unsupervised learning clusters data to group samples with similar characteristics, allowing for more accurate identification of stock pairs by considering not only traditional price data but also firm characteristics. Professor Han and his research team applied prominent clustering algorithms, such as k-means, DBSCAN, and agglomerative clustering, to the U.S. stock market and tested pairs trading strategies. The results show that long-short portfolios created using stock pairs selected through agglomerative clustering achieved an average annual return of 24.8% and a Sharpe ratio of 2.69. This performance is substantially superior to that of traditional pairs trading strategies. Notably, this study demonstrated that the strategy maintained high profitability even after accounting for transaction costs. “Identifying stock pairs taking firm characteristics into account provides much higher accuracy and profitability compared to simple price data-based methods. This research will significantly expand the possibilities of unsupervised learning in financial markets." said Professor Han. The research team confirmed through various robustness tests that these results were not due to data biases or chance. Furthermore, the strategy using clustering algorithms demonstrated high profitability even in extreme market conditions, such as financial crises. Professor Han expects this research to make significant contributions to the fields of financial engineering and machine learning. "We will be able to develop more sophisticated and efficient financial models through unsupervised learning," he said. "We will continue our research to develop various algorithms that can be used in actual financial markets." This research is expected to help pursue both stability and profitability in financial markets. Professor Chulwoo Han's research at Sungkyunkwan University has created a significant impact on both academic and industrial sectors in financial engineering and machine learning, providing important insights for future research directions.
- No. 258
- 2024-08-12
- 603
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How Brain Changes as We Age: Thalamocortical Connectivity and the Formation of Functional Networks
In our daily lives, our brains seamlessly process streams of visual information from the world around us while simultaneously understanding the causal structure of events. These essential cognitive functions, known as external sensory processing and internal world modeling, are critical for navigating complex environments. Our brain achieves this through large-scale functional systems responsible for these processes. Recently, an international collaboration of scientists led by the Institute for Basic Science (IBS) has explored the role of thalamocortical connectivity during the development of brain networks. One longstanding question in neuroscience is how the brain's large-scale functional networks form during development. This study investigated the changes in connectivity between the thalamus and cerebral cortex from infancy to adulthood and how these changes influence the formation of the brain's functional networks. For the first time, researchers have revealed that thalamocortical connectivity is crucial for the emergence and specialization of the brain's functional networks, particularly those processing external and internal information. Traditionally seen as a relay station for sensory information, the thalamus also influences higher cognitive functions. Sensory connections between the thalamus and cortex become established quickly at an early age, while higher-order cognitive connections develop later at maturity. However, the exact mechanisms and timeline of these developments have remained unclear. This study began to address these challenges by employing advanced neuroimaging techniques, transcriptomic analyses, and computational models on cross-sectional and longitudinal datasets, to map the development of thalamocortical connectivity across different age groups. This study revealed that during infancy, thalamocortical connectivity reflects early sensorimotor network differentiation and gene expression patterns related to brain development. As children grow, this connectivity shifts to establish connections with the salience network, differentiating external and internal functional cortical systems. Simulations confirmed thalamic connectivity's role in developing key features of the mature brain, such as functional segregation and the sensory-association axis. "Our study for the first time provides a detailed map of how thalamocortical connectivity contributes to the large-scale functional organization in the human brain from infancy through young adulthood," said lead author PARK Shinwon. "By integrating advanced neuroimaging techniques, gene expression analysis, and computational modeling, we were able to systematically track and analyze the changes in brain connectivity across different developmental stages. This comprehensive approach has allowed us to uncover the pivotal role of the thalamus in the emergence and specialization of brain networks." Unlike earlier studies that focused on regional properties of individual thalamic nuclei, this research provides a comprehensive view of the global integration of the thalamus into cortical networks. These findings offer potential implications for understanding and studying clinical conditions characterized by compromised internal and external processing, such as autism, schizophrenia, and other neurodevelopmental conditions. The corresponding author, HONG Seok Jun, a principal investigator at the IBS Center for Neuroscience Imaging Research stated, "Understanding how thalamocortical connectivity evolves and influences brain function provides a crucial foundation for identifying the mechanisms underlying neurodevelopmental conditions. This research opens up new possibilities for early diagnosis and targeted interventions, which could significantly improve outcomes for individuals with neurodevelopmental conditions." In the future, the researchers plan to investigate how thalamocortical connectivity changes in children with autism and how these changes correlate with clinical symptoms and cognitive functions. They also plan to expand their research focus to include other subcortical structures such as the striatum and cerebellum. This broader approach in systems neuroscience will help us gain a more comprehensive understanding of how various brain regions interact and develop. Figure 1. Thalamic connectopic maps (CMAP) and neocortical projection maps (NEOMAP) demonstrate the developmental changes in brain connectivity. Panel (a) shows CMAP 1 & 2 and NEOMAP 1 & 2 for infants (29–44 weeks), illustrating early differentiation of sensorimotor networks. Panel (b) displays these maps for children and young adults (8–22 years), highlighting the establishment of connections with the salience network and the differentiation between externally and internally oriented systems. Network profiles, sorted based on the Yeo-Krienan 7 Network Atlas, are depicted in box plots indicating the median and interquartile range (IQR). Panel (c) presents a schematic of the external-to-internal axis division derived from the NEOMAPs of childhood and young adulthood, showing the crucial role of the salience network.
- No. 257
- 2024-08-01
- 702
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Development of a high-capacity, long-life lithium-ion battery anode material using silicon-based high entropy alloy
National Research Foundation of Korea (President Lee Kwang-Bok) announced that Professor Ho-Seok Park's research team at Sungkyunkwan University has successfully developed a high-capacity, long-life lithium-ion battery* anode material using silicon-based high entropy alloy**. *Lithium-ion battery: A rechargeable secondary battery that uses lithium ions as the carrier and allows for repeated charge and discharge cycles through electrochemical oxidation and reduction reactions. It is used in devices such as smartphones and laptops. **High entropy alloy: Unlike conventional alloys where minor elements are added to a predominant element, HEAs mix multiple elements in relatively equal proportions of 5% or more without a predominant element, achieving a mixing entropy of 1.5R or higher. This allows for the realization of diverse material properties through combinations of alloys. A silicon-based anode* material has been developed to enhance the energy density of lithium-ion batteries. It is expected to overcome the capacity limits of graphite, which is currently used as a commercial anode material. *Negative electrode: Battery materials are broadly categorized into four main components: cathode material, anode material, separator, and electrolyte. The negative electrode, or anode material, undergoes reduction reactions during charging to store lithium and oxidation reactions during discharging to release lithium. With the global electric vehicle market expanding, battery technology competition has become increasingly fierce. Research efforts are actively underway to replace graphite, which has a capacity limit of 372mAh/g, with high-capacity silicon (theoretical capacity of 4200mAh/g), aiming to overcome this limitation. However, silicon materials suffer from issues such as low electrical conductivity and volume expansion during charge and discharge cycles, leading to compromised long-term stability. The research team has developed a silicon-based high entropy alloy material composed of various compositions of elements. By imparting multiple properties into a single material, they have addressed the performance degradation issues associated with silicon. Using high-energy ball milling* synthesis method, the research team successfully developed GaGeSiP3 material, incorporating high-capacity silicon (Si), highly reactive phosphorus (P), fast lithium-ion conductivity germanium (Ge), and self-healing liquid metal gallium (Ga). They minimized the process complexity while including the advantages of these elements. * Ball milling: Ball milling is a grinding device composed of a metal cylinder and balls, where the cylinder rotates, causing the balls and materials to grind or mix into fine powders due to friction and centrifugal forces. In the case of GaGeSiP3 material, it has demonstrated a high rate capability* with a capacity of 949mAh/g even at high current densities, and it maintained a high capacity of 1,121mAh/g after 2,000 charge-discharge cycles. * Rate capability: Ability of a battery to maintain its capacity retention rate depending on the speed of charging and discharging Professor Ho-Seok Park stated, "This research not only proposes solutions to address the drawbacks of silicon, a key material for enhancing the energy density of lithium-ion batteries, but also holds significance in being the first to implement highly reactive phosphorus atoms in the recently acclaimed high entropy alloy materials." Furthermore, this research has set design criteria for silicon-based high entropy alloy materials. As such, future research plans include synthesizing high entropy materials of various combinations to optimize structure and composition, as well as conducting additional studies on anode optimization to enhance battery performance. Supported by the Ministry of Science and ICT and the National Research Foundation of "Center for 2D Elementary Surface Redox Energy Storage" and "Brain Pool Program" for attracting outstanding international scientists, the outcomes of this study were published in the international energy journal 'Energy & Environmental Science' (IF=32.5) on April 16th. Figure 1. Schematic diagram of synthesis and design of high-entropy materials. Using high-energy ball milling to mix zinc, copper, aluminum, gallium, germanium, silicon cations, and phosphorus anions in a certain ratio, synthesize a schematic diagram of silicon-based high-entropy alloy materials and demonstrate enhancement of electrochemical and mechanical properties through high-entropy alloying Figure 2. Comparison of structure and electrochemical performance between silicon-based medium-entropy and high-entropy alloys, and schematic diagram illustrating structural changes in high-entropy alloys due to lithium-ion storage. Schematic diagram demonstrating enhanced electrochemical performance through high-entropy alloying, and reversible structural changes due to lithium-ion storage.
- No. 256
- 2024-07-23
- 860
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Prof. Jung-Hoon Han has published a paper in the prestigious Academy of Management Journal
Prof. Jung-Hoon Han of Sungkyunkwan University’s SKK GSB(Graduate School of Business) has published a paper in the prestigious Academy of Management Journal, shedding light on when misconduct by high-status firms escalates into scandals. Prof. Han and Professors Timothy G. Pollock (University of Tennessee, Knoxville) and Scott Graffin (University of Georgia) analyzed 2015–2018 data breaches involving publicly traded U.S. firms. They question the widely held assumption that scandals usually stem from high-status firms’ misconduct and demonstrate that the development of scandals depends on the perpetrating companies’ surrounding environment. For example, if several large tech companies such as Google, Meta (owner of Facebook) and X (formerly Twitter), and the supermarket chain Walmart engaged in the same misconduct, the media would be less likely to report on and scandalize Walmart’s misconduct as it is easier to tell a story based on tech companies’ all doing the wrong thing than to try to crowbar a retail firm into the narrative. The key takeaway is that journalists are more likely to report on and scandalize corporate misconduct when there is a clear industry-based pattern. The harder it is to identify a set of similarities that helps journalists tell a simple story, the lower the likelihood that any one firm’s misconduct will be scandalized. These findings have significant implications for companies’ crisis management strategies. When facing misconduct allegations, firms should address public concerns by highlighting how they differ from other industry leaders who have engaged in misconduct and by stressing that their actions do not reflect an industry-wide failure. From a preventive standpoint, firms should exercise caution when adopting practices from other high-status firms to avoid scandalization. Journal: Academy of Management Journal Title: Now you see me: How status and categorical proximity shape misconduct scandalization DOI: https://doi.org/10.5465/amj.2022.0365 First Author: Prof. Jung-Hoon Han of Sungkyunkwan University’s SKK GSB(Graduate School of Business) The figure above illustrates that while high-status firms’ misconduct is more likely to become scandalized, such tendency is amplified when high-status firms’ misconduct has been prevalent within the same industry (a). In contrast, the prevalence of high-status firms’ misconduct outside an industry attenuates the scandalizing effect of focal firm’s status (b).
- No. 255
- 2024-07-09
- 873
