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X-WR-CALNAME:Biomedical Mathematics Group
X-ORIGINAL-URL:https://www.ibs.re.kr/bimag
X-WR-CALDESC:Events for Biomedical Mathematics Group
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BEGIN:VTIMEZONE
TZID:Asia/Seoul
BEGIN:STANDARD
TZOFFSETFROM:+0900
TZOFFSETTO:+0900
TZNAME:KST
DTSTART:20220101T000000
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END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250703T160000
DTEND;TZID=Asia/Seoul:20250703T170000
DTSTAMP:20260429T221739
CREATED:20250628T074404Z
LAST-MODIFIED:20250630T055202Z
UID:11207-1751558400-1751562000@www.ibs.re.kr
SUMMARY:Jihun Han - Bridging PDEs and machine learning
DESCRIPTION:Abstract: This talk consists of two main parts. In the first part\, I will discuss a numerical method for solving PDEs based on a stochastic representation of the solution. This approach captures the underlying particle dynamics associated with the physical processes described by the PDE. By aggregating information from the particles’ collective exploration\, the method iteratively reinforces the approximation toward the solution. I will cover its analysis regarding the trainability and highlight its effectiveness across a broad class of problems\, including elliptic equations with interfaces\, multiscale structures\, and perforated domains\, as well as hyperbolic-type problems such as the Eikonal and Burgers equations.\nIn the second part\, I will present a method for learning in-between imagery dynamics. This approach integrates PDE models within latent spaces to enhance both learning capability and interpretability. Notably\, this method demonstrates robustness in capturing intricate dynamics\, such as rotation and outflow\, which pose significant challenges for current state-of-the-art optimal transport methods.
URL:https://www.ibs.re.kr/bimag/event/ji-hoon-han-bridging-pdes-and-machine-learning/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250627T160000
DTEND;TZID=Asia/Seoul:20250627T170000
DTSTAMP:20260429T221739
CREATED:20250615T110211Z
LAST-MODIFIED:20250615T110211Z
UID:11180-1751040000-1751043600@www.ibs.re.kr
SUMMARY:U Jin Choi - Simulation-Free Schrodinger Bridges Via Score and Flow Matching (by Tong et al\, AISTATS 2024).
DESCRIPTION:Abstract: 임의로 정한 Initial Distribution Q1 와 Terminal Distribution Q2가 주어 졌을 때 시점과 종점 사이의 contiinious time상에  정의 되는 의미 있는 최적의 Probability Path Measure P 를 찾는 Schrodinger Bridges Problem 은 자연과학\,공학\, 의료 및 생명공학\,경제학 및 금융공학 등의 여러 분야에 나타나는 모델들을 푸는 Unified AI Model 사용 되고 있습니다. Schrodinger Bridges Problem은  유일한 해가 존재 하는 정리는( Follmer\,1988)  증명 되었으므로 데이터를 이용하여  Neural Network Models에 대한 효율적으로 학습방법\,  빠른 알고리즘 연구에 집중 되고 있습니다. Tong et al 연구팀은 2023년 부터 ODE에 기반한 획기적인 생성모델인  Flow Matching for Generative Modeling 기법을  SDE 기반 Diffusion Generative Models에 접목하여 Schrodinger Bridges Problem의 해법을 제시하였습니다.
URL:https://www.ibs.re.kr/bimag/event/u-jin-choi-simulation-free-schrodinger-bridges-via-score-and-flow-matching-by-tong-et-al-aistats-2024/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250428T110000
DTEND;TZID=Asia/Seoul:20250428T120000
DTSTAMP:20260429T221739
CREATED:20250414T004912Z
LAST-MODIFIED:20250420T085852Z
UID:10975-1745838000-1745841600@www.ibs.re.kr
SUMMARY:FoodSeq: Using Genomics to Track and Study Diet - Lawrence David
DESCRIPTION:Abstract\nDietary assessment is crucial for understanding the relationship between diet and health. Yet traditional recall-based methods for tracking diet often face challenges like participant compliance and accurate recall. To address these issues\, our lab at Duke University has developed FoodSeq\, a genomic approach to track food intake through DNA sequencing of stool samples. In this talk\, I will explain how FoodSeq can identify and quantify dietary species\, allowing for objective and comprehensive monitoring of food consumption. We will explore the methodology behind FoodSeq\, including DNA extraction\, amplification\, and sequencing\, as well as data analysis. I will then present case studies demonstrating how FoodSeq can be used in clinical studies involving patients undergoing hematopoietic stem cell transplant\, highlighting the potential to contribute insights into nutrition\, health\, and the microbiome.
URL:https://www.ibs.re.kr/bimag/event/foodseq-using-genomics-to-track-and-study-diet-lawrence-david/
LOCATION:Conference room\, (B109)\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ATTACH;FMTTYPE=image/jpeg:https://www.ibs.re.kr/bimag/cms/wp-content/uploads/2025/04/0604222-e1745139516483.jpg
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250422T160000
DTEND;TZID=Asia/Seoul:20250422T170000
DTSTAMP:20260429T221739
CREATED:20250421T005522Z
LAST-MODIFIED:20250422T064931Z
UID:10994-1745337600-1745341200@www.ibs.re.kr
SUMMARY:Dimensionality Reduction and Summary-Statistical Modeling in Genetic Studies - Fatemeh Yavartanoo
DESCRIPTION:Abstract: \nThis presentation introduces DRLPC and a refined summary-statistics method to improve genetic association analysis. Applications to cognition\, neurodegenerative diseases\, and high cholesterol are discussed\, with future directions in single-cell analysis and drug target discovery.
URL:https://www.ibs.re.kr/bimag/event/tba-fatemeh-yavartanoo/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ATTACH;FMTTYPE=image/jpeg:https://www.ibs.re.kr/bimag/cms/wp-content/uploads/2025/04/1705897753193.jpeg
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250306T130000
DTEND;TZID=Asia/Seoul:20250306T153000
DTSTAMP:20260429T221739
CREATED:20250226T071803Z
LAST-MODIFIED:20250226T072211Z
UID:10813-1741266000-1741275000@www.ibs.re.kr
SUMMARY:심리학이 알려주는 연구의 기술: 논리적 사고부터 논문 작성까지 - 서수연
DESCRIPTION:본 세미나에서는 성신여자대학교 서수연 교수님께서 “심리학이 알려주는 연구의 기술: 논리적 사고부터 논문 작성까지”라는 내용으로 강연을 해주실 예정입니다. \n  \n 
URL:https://www.ibs.re.kr/bimag/event/psychology-and-research/
LOCATION:Daejeon
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20250114T110000
DTEND;TZID=Asia/Seoul:20250114T120000
DTSTAMP:20260429T221739
CREATED:20241231T015243Z
LAST-MODIFIED:20250109T125003Z
UID:10499-1736852400-1736856000@www.ibs.re.kr
SUMMARY:Biomolecular Condensates: Principles and Models\, Jeong-Mo Choi
DESCRIPTION:Over the past decade\, the phase behavior of biomolecules has garnered significant attention\, particularly due to its biological implications\, such as the reversible formation and dissociation of biomolecular condensates. These condensates perform diverse and essential functions within cells\, including the acceleration of chemical reactions. Recent advances aim to uncover the fundamental principles of these systems and harness them as tools for engineering cellular processes in synthetic biology. In this talk\, I will discuss the key principles that govern the behaviors of biomolecular condensates and introduce several (semi-)analytical models that provide both qualitative insights and quantitative predictions. These models serve as a foundation for understanding and leveraging condensate-driven phenomena in biological systems.
URL:https://www.ibs.re.kr/bimag/event/tbd-jeong-mo-choi/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20241230T110000
DTEND;TZID=Asia/Seoul:20241230T120000
DTSTAMP:20260429T221739
CREATED:20241222T065319Z
LAST-MODIFIED:20241222T065404Z
UID:10424-1735556400-1735560000@www.ibs.re.kr
SUMMARY:Enhanced Gaussian Process Surrogates for Optimization and Sampling by Pure Exploration - Hwanwoo Kim
DESCRIPTION:Abstract: \nIn this talk\, we propose novel noise-free Bayesian optimization strategies that rely on a random exploration step to enhance the accuracy of Gaussian process surrogate models. The new algorithms retain the ease of implementation of the classical GP-UCB algorithm\, but the additional random exploration step accelerates their convergence\, nearly achieving the optimal convergence rate. Furthermore\, to facilitate Bayesian inference with an intractable likelihood\, we propose to utilize the optimization iterates as design points to build a Gaussian process surrogate model for the unnormalized log-posterior density. We provide bounds for the Hellinger distance between the true and the approximate posterior distributions in terms of the number of design points. The effectiveness of our algorithms is demonstrated in benchmark non-convex test functions for optimization\, and in a black-box engineering design problem. We also showcase the effectiveness of our posterior approximation approach in Bayesian inference for parameters of dynamical systems.
URL:https://www.ibs.re.kr/bimag/event/enhanced-gaussian-process-surrogates-for-optimization-and-sampling-by-pure-exploration-hwanwoo-kim/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20241227T100000
DTEND;TZID=Asia/Seoul:20241227T120000
DTSTAMP:20260429T221739
CREATED:20241022T001840Z
LAST-MODIFIED:20241226T235355Z
UID:10197-1735293600-1735300800@www.ibs.re.kr
SUMMARY:Diffusion Posterior Sampling for Linear Inverse Problem Solving- A Filtering Perspective - U Jin Choi
DESCRIPTION:In this talk\, we discuss the paper : “Diffusion Posterior Sampling for Linear Inverse Problem Solving- A Filtering Perspective” by Z. Dou& Y. Song \n\n\nDiffusion models have achieved tremendous success in generating high-dimensional data like images\, videos and audio. These models provide powerful data priors that can solve linear inverse problems in zero shot through Bayesian posterior sampling. However\, exact posterior sampling for diffusion models is intractable. Current solutions often hinge on approximations that are either computationally expensive or lack strong theoretical guarantees. In this work\, we introduce an efficient diffusion sampling algorithm for linear inverse problems that is guaranteed to be asymptotically accurate. We reveal a link between Bayesian posterior sampling and Bayesian filtering in diffusion models\, proving the former as a specific instance of the latter. Our method\, termed filtering posterior sampling\, leverages sequential Monte Carlo methods to solve the corresponding filtering problem. It seamlessly integrates with all Markovian diffusion samplers\, requires no model re-training\, and guarantees accurate samples from the Bayesian posterior as particle counts rise. Empirical tests demonstrate that our method generates better or comparable results than leading zero-shot diffusion posterior samplers on tasks like image inpainting\, super-resolution\, and deblurring.
URL:https://www.ibs.re.kr/bimag/event/diffusion-posterior-sampling-for-linear-inverse-problem-solving-a-filtering-perspective-u-jin-choi/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20241216T150000
DTEND;TZID=Asia/Seoul:20241216T170000
DTSTAMP:20260429T221739
CREATED:20241022T001632Z
LAST-MODIFIED:20241208T082830Z
UID:10195-1734361200-1734368400@www.ibs.re.kr
SUMMARY:Solving Inverse Problems in Medical Imaging with Score-Based Generative Models - U Jin Choi
DESCRIPTION:In this talk\, we discuss the paper : “Solving Inverse Problems in Medical Imaging with Score-Based Generative Models” by Y Song et al. \nReconstructing medical images from partial measurements is an important inverse problem in Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). Existing solutions based on machine learning typically train a model to directly map measurements to medical images\, leveraging a training dataset of paired images and measurements. These measurements are typically synthesized from images using a fixed physical model of the measurement process\, which hinders the generalization capability of models to unknown measurement processes. To address this issue\, we propose a fully unsupervised technique for inverse problem solving\, leveraging the recently introduced score-based generative models. Specifically\, we first train a score-based generative model on medical images to capture their prior distribution. Given measurements and a physical model of the measurement process at test time\, we introduce a sampling method to reconstruct an image consistent with both the prior and the observed measurements. Our method does not assume a fixed measurement process during training\, and can thus be flexibly adapted to different measurement processes at test time. Empirically\, we observe comparable or better performance to supervised learning techniques in several medical imaging tasks in CT and MRI\, while demonstrating significantly better generalization to unknown measurement processes.
URL:https://www.ibs.re.kr/bimag/event/solving-inverse-problems-in-medical-imaging-with-score-based-generative-models-u-jin-choi/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20241209T160000
DTEND;TZID=Asia/Seoul:20241209T170000
DTSTAMP:20260429T221739
CREATED:20241204T084453Z
LAST-MODIFIED:20241204T084453Z
UID:10334-1733760000-1733763600@www.ibs.re.kr
SUMMARY:Theoretical studies on biological oscillations by using waveform data and mathematical models - Shingo Gibo
DESCRIPTION:Title: Theoretical studies on biological oscillations by using waveform data and mathematical models \nAbstract: Temporal waveforms of biological oscillations are of various shapes. In our research\, we have explored the functional implications of these waveform shapes. In particular\, we theoretically showed that the period of circadian clocks is proportional to the waveform distortion from sinusoidal wave. It suggests that the circadian period can be stable against temperature changes only if the waveform becomes more distorted at higher temperatures. In this talk\, I will explain my past research and discuss my future plans. \n\nReference:\n[1] Shingo Gibo\, Gen Kurosawa\, Non-sinusoidal Waveform in Temperature Compensated Circadian Oscillations\, Biophysical Journal 116 (4) 741-751 (2019). doi: 10.1016/j.bpj.2018.12.022\n[2] Shingo Gibo\, Gen Kurosawa\, Theoretical study on the regulation of circadian rhythms by RNA methylation\, Journal of Theoretical Biology 490\, 110140 (2020). doi; 10.1016/j.jtbi.2019.110140\n[3] Shingo Gibo\, Teiji Kunihiro\, Tetsuo Hatsuda\, Gen Kurosawa\, Waveform distortion for temperature compensation and synchronization in circadian rhythms: An approach based on the renormalization group method\, arXiv (2024). arXiv:2409.02526
URL:https://www.ibs.re.kr/bimag/event/theoretical-studies-on-biological-oscillations-by-using-waveform-data-and-mathematical-models-shingo-gibo/
LOCATION:Daejeon
CATEGORIES:Biomedical Mathematics Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240905T100000
DTEND;TZID=Asia/Seoul:20240905T110000
DTSTAMP:20260429T221739
CREATED:20240830T085940Z
LAST-MODIFIED:20240904T030529Z
UID:10010-1725530400-1725534000@www.ibs.re.kr
SUMMARY:Make Your Science Friendly: A Guide to Engaging Visuals - Sunghwan Bae
DESCRIPTION:The talk will be hybrid\, participants may join via Zoom with the following link: https://us06web.zoom.us/j/99567630778?pwd=N2ZrUWtqZzJ0YURVTzlZT3JJR3FUQT09
URL:https://www.ibs.re.kr/bimag/event/make-your-science-friendly-a-guide-to-engaging-visuals-sunghwan-bae/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240807T160000
DTEND;TZID=Asia/Seoul:20240807T170000
DTSTAMP:20260429T221739
CREATED:20240805T002501Z
LAST-MODIFIED:20240807T012802Z
UID:9911-1723046400-1723050000@www.ibs.re.kr
SUMMARY:Uncovering personalized glucose responses and circadian rhythms from multiple wearable biosensors with Bayesian dynamical modeling
DESCRIPTION:Abstract: \nWearable biosensors measure physiological variables with high temporal resolution over multiple days and are increasingly employed in clinical settings\, such as continuous glucose monitoring in diabetes care. Such datasets bring new opportunities and challenges\, and patients\, clinicians\, and researchers are today faced with a common challenge: how to best summarize and capture relevant information from multimodal wearable time series? Here\, we aim to provide insights into individual glucose dynamics and their relationships with food and drink ingestion\, time of day\, and coupling with other physiological states such as physical and heart activity. To this end\, we generate and analyze multiple wearable device data through the lens of a parsimonious mathematical model with interpretable components and parameters. A key innovation of our method is that the models are learned on a personalized level for each participant within a Bayesian framework\, which enables the characterization of interindividual heterogeneity in features such as the glucose response time following meals or underlying circadian baseline rhythm. I will also describe how we are currently applying this framework in the context of gestational diabetes.
URL:https://www.ibs.re.kr/bimag/event/uncovering-personalized-glucose-responses-and-circadian-rhythms-from-multiple-wearable-biosensors-with-bayesian-dynamical-modeling/
LOCATION:ZOOM ID: 997 8258 4700 (Biomedical Mathematics Online Colloquium)\, (pw: 1234)
CATEGORIES:Biomedical Mathematics Seminar
ATTACH;FMTTYPE=image/jpeg:https://www.ibs.re.kr/bimag/cms/wp-content/uploads/2024/08/20240305_234410-e1722990001623.jpg
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240731T160000
DTEND;TZID=Asia/Seoul:20240731T170000
DTSTAMP:20260429T221739
CREATED:20240728T141528Z
LAST-MODIFIED:20240728T141528Z
UID:9889-1722441600-1722445200@www.ibs.re.kr
SUMMARY:Hyukpyo Hong\, Koopman representation: Linear representation – not an approximation – of nonlinear dynamics
DESCRIPTION:Abstract: A system of ordinary differential equations (ODEs) is one of the most widely used tools to describe a deterministic dynamical system. In general\, such ODEs involve nonlinear equations\, which make analysis of dynamical systems difficult. In this talk\, we introduce Koopman theory\, which offers a linear representation – not an approximation – of nonlinear dynamics. In particular\, we present a data-driven algorithm to find such a linear representation
URL:https://www.ibs.re.kr/bimag/event/hyukpyo-hong-koopman-representation-linear-representation-not-an-approximation-of-nonlinear-dynamics/
LOCATION:Daejeon
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240625T140000
DTEND;TZID=Asia/Seoul:20240625T150000
DTSTAMP:20260429T221739
CREATED:20240623T122242Z
LAST-MODIFIED:20240625T002727Z
UID:9721-1719324000-1719327600@www.ibs.re.kr
SUMMARY:Hyungsuk Tak\, Statistical Challenges in Astronomical Time Delay Estimation (Cancelled)
DESCRIPTION:I present time delay estimation problems in astronomy as a part of time delay cosmography to infer the Hubble constant\, the current expansion rate of the Universe. Time delay cosmography is based on strong gravitational lensing\, an effect that multiple images of the same astronomical object appear in the sky because paths of the light (from the object to the Earth) are bent by the strong gravitational field of an intervening galaxy. By measuring brightness of multiply-lensed images\, we obtain several time series data of brightness\, and time delays can be inferred by modeling these data. I focus on challenges in modeling these time series data and computational issues in fitting the models. In particular\, I explain continuous-time auto-regressive models to account for stochastic variability of the time series data\, and several Monte Carlo samplers to sample from the target posterior distributions with multiple modes. At the end of the talk\, I show how these time delays estimates contribute to the Hubble constant estimation. Two main references of this talk are arXiv2207.09327 and arXiv2308.13018.
URL:https://www.ibs.re.kr/bimag/event/hyungsuk-tak-statistical-challenges-in-astronomical-time-delay-estimation/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240527T160000
DTEND;TZID=Asia/Seoul:20240527T170000
DTSTAMP:20260429T221739
CREATED:20240326T150018Z
LAST-MODIFIED:20240326T150018Z
UID:9426-1716825600-1716829200@www.ibs.re.kr
SUMMARY:Timothy L. Downing\, Biophysical Regulation of Cell Fate\, from ECM to Nuclear Chromatin
DESCRIPTION:Abstract: The Downing lab investigates the intricate biophysical interactions between cells and their environment\, elucidating their role in modulating adult cell behavior and phenotypic transitions via epigenetic regulation of gene expression. Leveraging diverse genome-scale sequencing techniques\, we decipher mechanisms underlying cell fate transitions mediated through dynamic regulation of nuclear chromatin and heterogeneous gene activity. Our research endeavors aim to engineer molecular tools and biomaterials to synthetically modulate the epigenome\, enhancing control over cell fate and behavior. In this seminar presentation\, I will focus on how signaling pathways governing cell-cell and cell-ECM communication contribute to observed fate transitions during the acquisition of stemness phenotypes and lineage plasticity\, particularly in iPSC reprogramming and cancer contexts.
URL:https://www.ibs.re.kr/bimag/event/timothy-l-downing-biophysical-regulation-of-cell-fate-from-ecm-to-nuclear-chromatin/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240214T110000
DTEND;TZID=Asia/Seoul:20240214T120000
DTSTAMP:20260429T221739
CREATED:20240209T001853Z
LAST-MODIFIED:20240209T001853Z
UID:9194-1707908400-1707912000@www.ibs.re.kr
SUMMARY:Kang MIn Lee\, Oscillation in brain and its potential role in inter-areal communication
DESCRIPTION:Abstract: Through the past decades\, electrophysiological experiments have revealed that extracellular electrical potential of brain show diverse rhythmic activity. Called ‘Local Field Potential(LFP)’\, those rhythmic activities are thought to reflect populational activity of neurons. In this talk\, I will introduce basic concepts on LFP and its generation mechanisms. Then\, roles of LFP in brain inter-areal communication will be presented. Particularly\, hypothesis on frequency specific communication and their experimental evidences will be main topics.
URL:https://www.ibs.re.kr/bimag/event/kang-min-lee-oscillation-in-brain-and-its-potential-role-in-inter-areal-communication/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240205T140000
DTEND;TZID=Asia/Seoul:20240205T150000
DTSTAMP:20260429T221739
CREATED:20240129T052339Z
LAST-MODIFIED:20240129T052339Z
UID:9163-1707141600-1707145200@www.ibs.re.kr
SUMMARY:Jong Kyoung Kim\, Dissecting cellular heterogeneity and plasticity in adipose tissue
DESCRIPTION:Abstract: Cell-to-cell variability in gene expression exists even in a homogeneous population of cells. Dissecting such cellular heterogeneity within a biological system is a prerequisite for understanding how a biological system is developed\, homeostatically regulated\, and responds to external perturbations. Single-cell RNA sequencing (scRNA-seq) allows the quantitative and unbiased characterization of cellular heterogeneity by providing genome-wide molecular profiles from tens of thousands of individual cells. Single-cell sequencing is expanding to combine genomic\, epigenomic\, and transcriptomic features with environmental cues from the same single cell. In this talk\, I demonstrate how scRNA-seq can be applied to dissect cellular heterogeneity and plasticity of adipose tissue\, and discuss related computational challenges.
URL:https://www.ibs.re.kr/bimag/event/jong-kyoung-kim-dissecting-cellular-heterogeneity-and-plasticity-in-adipose-tissue/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240117T110000
DTEND;TZID=Asia/Seoul:20240117T120000
DTSTAMP:20260429T221739
CREATED:20240111T072709Z
LAST-MODIFIED:20240111T073014Z
UID:9084-1705489200-1705492800@www.ibs.re.kr
SUMMARY:Junil Kim\, TENET+: a tool for reconstructing gene networks by integrating single cell expression and chromatin accessibility data
DESCRIPTION:Abstract: Reconstruction of gene regulatory networks (GRNs) is a powerful approach to capture a prioritized gene set controlling cellular processes. In our previous study\, we developed TENET a GRN reconstructor from single cell RNA sequencing (scRNAseq). TENET has a superior capability to identify key regulators compared with other algorithms. However\, accurate inference of gene regulation is still challenging. Here\, we suggest an integrative strategy called TENET+ by combining single cell transcriptome and chromatin accessibility data. TENET+ predicts target genes and open chromatin regions associated with transcription factors (TFs) and links the target regions to their corresponding target gene. As a result\, TENET+ can infer regulatory triplets of TF\, target gene\, and enhancer. By applying TENET+ to a paired scRNAseq and scATACseq dataset of human peripheral blood mononuclear cells\, we found critical regulators and their epigenetic regulations for the differentiations of CD4 T cells\, CD8 T cells\, B cells and monocytes. Interestingly\, not only did TENET+ predict several top regulators of each cell type which were not predicted by the motif-based tool SCENIC\, but we also found that TENET+ outperformed SCENIC in prioritizing critical regulators by using a cell type associated gene list. Furthermore\, utilizing and modeling regulatory triplets\, we can infer a comprehensive epigenetic GRN. In sum\, TENET+ is a tool predicting epigenetic gene regulatory programs for various types of datasets in an unbiased way\, suggesting that novel epigenetic regulations can be identified by TENET+. \nGithub page: https://github.com/hg0426/TENETPLUS.
URL:https://www.ibs.re.kr/bimag/event/junil-kim-tenet-a-tool-for-reconstructing-gene-networks-by-integrating-single-cell-expression-and-chromatin-accessibility-data/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ATTACH;FMTTYPE=image/jpeg:https://www.ibs.re.kr/bimag/cms/wp-content/uploads/2024/01/프로필사진-e1704958090187.jpg
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20240109T100000
DTEND;TZID=Asia/Seoul:20240109T110000
DTSTAMP:20260429T221739
CREATED:20240103T102249Z
LAST-MODIFIED:20240107T033247Z
UID:9021-1704794400-1704798000@www.ibs.re.kr
SUMMARY:Hyung Jin Choi\, A Normative Framework Dissociates Need and Motivation in Hypothalamic Neurons
DESCRIPTION:Abstract: Physiological needs evoke motivational drives to produce natural behaviours for survival. However\, the temporally intertwined dynamics of need and motivation have made it challenging to differentiate these two components in previous experimental paradigms. Based on classic homeostatic theories\, we established a normative framework to derive computational models of neural activity and behaviours for need-encoding and motivation-encoding neurons during events that induce predicted gain or loss. We further developed simple and intuitive experimental paradigms that enabled us to distinguish the distinct roles of subpopulations of neurons in the hypothalamus. Our results show that AgRP neurons and LHLepR neurons are consistent with need and motivation\, respectively. Our study provides a parsimonious understanding of how distinct hypothalamic neurons separately encode need and motivation to produce adaptive behaviours for maintaining homeostasis.\n\nZOOM ID: 997 8258 4700 (Biomedical Mathematics Online Colloquium)\, (pw: 1234)
URL:https://www.ibs.re.kr/bimag/event/hyung-jin-choi-a-normative-framework-dissociates-need-and-motivation-in-hypothalamic-neurons-3/
LOCATION:B232 Seminar Room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ATTACH;FMTTYPE=image/jpeg:https://www.ibs.re.kr/bimag/cms/wp-content/uploads/2024/01/최형진-사진-HAHN1836-실험가운-해부학-1-1-1-e1704595806914.jpg
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230926T160000
DTEND;TZID=Asia/Seoul:20230926T170000
DTSTAMP:20260429T221739
CREATED:20230924T061833Z
LAST-MODIFIED:20230924T061833Z
UID:8555-1695744000-1695747600@www.ibs.re.kr
SUMMARY:Jonathan Rubin\, Qualitative inverse problems: mapping from limited data to properties of dynamics and parameter values for ODE models
DESCRIPTION:
URL:https://www.ibs.re.kr/bimag/event/jonathan-rubin-qualitative-inverse-problems-mapping-from-limited-data-to-properties-of-dynamics-and-parameter-values-for-ode-models-2/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230918T160000
DTEND;TZID=Asia/Seoul:20230918T170000
DTSTAMP:20260429T221739
CREATED:20230918T080118Z
LAST-MODIFIED:20230918T080118Z
UID:8524-1695052800-1695056400@www.ibs.re.kr
SUMMARY:Balazs Erdos\, Quantifying the dynamics of postmeal metabolism: Inference from challenge test data
DESCRIPTION:
URL:https://www.ibs.re.kr/bimag/event/balazs-erdos-quantifying-the-dynamics-of-postmeal-metabolism-inference-from-challenge-test-data/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230906T160000
DTEND;TZID=Asia/Seoul:20230906T170000
DTSTAMP:20260429T221739
CREATED:20230904T132811Z
LAST-MODIFIED:20230904T132811Z
UID:8487-1694016000-1694019600@www.ibs.re.kr
SUMMARY:Jonathan Rubin\, Multiple timescale modeling for neural systems
DESCRIPTION:Abstract \nMathematical models of biological systems\, including neurons\, often feature components that evolve on very different timescales. Mathematical analysis of these multi-timescale systems can be greatly simplified by partitioning them into subsystems that evolve on different time scales. The subsystems are then analyzed semi-independently\, using a technique called fast-slow analysis. I will briefly describe the fast-slow analysis technique and its application to neuronal bursting oscillations and basic coupled neuron modeling. After this\, I will discuss fancier forms of dynamics such as canard oscillations\, mixed-mode oscillations\, and three-timescale dynamics. Although these examples all involve neural systems\, the methods can and have been applied to other biological\, chemical\, and physical systems.
URL:https://www.ibs.re.kr/bimag/event/jonathan-rubin-multiple-timescale-modeling-for-neural-systems/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230608T110000
DTEND;TZID=Asia/Seoul:20230608T120000
DTSTAMP:20260429T221739
CREATED:20230601T080809Z
LAST-MODIFIED:20230605T043518Z
UID:7870-1686222000-1686225600@www.ibs.re.kr
SUMMARY:Seonjin Kim\, Nonparametric vs Parametric Regression
DESCRIPTION:To understand nonparametric regression\, we should know first what the parametric model is. Simply speaking\, the parametric regression model consists of many assumptions and the nonparametric regression model eases the assumptions. I will introduce what assumptions the parametric regression model has and how the nonparametric regression model relieves them. In addition\, their pros and cons will be also presented.
URL:https://www.ibs.re.kr/bimag/event/nonparametric-vs-parametric-regression/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230530T160000
DTEND;TZID=Asia/Seoul:20230530T170000
DTSTAMP:20260429T221739
CREATED:20230524T125426Z
LAST-MODIFIED:20230524T125651Z
UID:7788-1685462400-1685466000@www.ibs.re.kr
SUMMARY:Trivial but not trivial things in data science: From a statistical perspective
DESCRIPTION:TBA
URL:https://www.ibs.re.kr/bimag/event/t/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230525T110000
DTEND;TZID=Asia/Seoul:20230525T120000
DTSTAMP:20260429T221739
CREATED:20230522T134427Z
LAST-MODIFIED:20230522T134449Z
UID:7767-1685012400-1685016000@www.ibs.re.kr
SUMMARY:Nonparametric predictive model for sparse and irregular longitudinal data
DESCRIPTION:We propose a kernel-based estimator to predict the mean response trajectory for sparse and irregularly measured longitudinal data. The kernel estimator is constructed by imposing weights based on the subject-wise similarity on L2 metric space between predictor trajectories\, where we assume that an analogous fashion in predictor trajectories over time would result in a similar trend in the response trajectory among subjects. In order to deal with the curse of dimensionality caused by the multiple predictors\, we propose an appealing multiplicative model with multivariate Gaussian kernels. This model is capable of achieving dimension reduction as well as selecting functional covariates with predictive significance. The asymptotic properties of the proposed nonparametric estimator are investigated under mild regularity conditions. We illustrate the robustness and flexibility of our proposed method via the simulation study and an application to Framingham Heart Study
URL:https://www.ibs.re.kr/bimag/event/2023-05-25-seminar/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230522T120000
DTEND;TZID=Asia/Seoul:20230522T130000
DTSTAMP:20260429T221739
CREATED:20230509T062709Z
LAST-MODIFIED:20230509T062709Z
UID:7730-1684756800-1684760400@www.ibs.re.kr
SUMMARY:Pan Li\, Modeling the circadian control of cardiac function
DESCRIPTION:Abstract: TBA
URL:https://www.ibs.re.kr/bimag/event/pan-li-modeling-the-circadian-control-of-cardiac-function/
LOCATION:IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230508T160000
DTEND;TZID=Asia/Seoul:20230508T170000
DTSTAMP:20260429T221739
CREATED:20230425T045600Z
LAST-MODIFIED:20230425T045600Z
UID:7637-1683561600-1683565200@www.ibs.re.kr
SUMMARY:Kyongwon Kim\, On sufficient graphical models
DESCRIPTION:We introduce a sufficient graphical model by applying the recently developed nonlinear sufficient dimension reduction techniques to the evaluation of conditional independence. The graphical model is nonparametric in nature\, as it does not make distributional assumptions such as the Gaussian or copula Gaussian assumptions. However\, unlike a fully nonparametric graphical model\, which relies on the high-dimensional kernel to characterize conditional independence\,  our graphical model is based on conditional independence given a set of sufficient predictors with a substantially reduced dimension. In this way we avoid the curse of dimensionality that comes with a high-dimensional kernel. We develop the population-level properties\,  convergence rate\, and variable selection consistency of our estimate. \nBy simulation comparisons and an analysis of the DREAM 4 Challenge data set\, we demonstrate that our method outperforms the existing methods when the Gaussian or copula Gaussian assumptions are violated\, and its performance remains excellent in the high-dimensional setting.
URL:https://www.ibs.re.kr/bimag/event/kyongwon-kim-on-sufficient-graphical-models/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230504T161500
DTEND;TZID=Asia/Seoul:20230504T171500
DTSTAMP:20260429T221739
CREATED:20230409T053139Z
LAST-MODIFIED:20230414T024516Z
UID:7585-1683216900-1683220500@www.ibs.re.kr
SUMMARY:Uncovering the mechanisms of pattern formation and emergent collective behaviors in myxobacteria
DESCRIPTION:Collective cell movement is critical to the emergent properties of many multicellular systems including microbial self-organization in biofilms\, wound healing\, and cancer metastasis. However\, even the best-studied systems lack a complete picture of how diverse physical and chemical cues act upon individual cells to ensure coordinated multicellular behavior. Myxococcus xanthus is a model bacteria famous for its coordinated multicellular behavior resulting in dynamic patterns formation. For example\, when starving millions of cells coordinate their movement to organize into fruiting bodies – aggregates containing tens of thousands of bacteria. Relating these complex self-organization patterns to the behavior of individual cells is a complex-reverse engineering problem that cannot be solved solely by experimental research. In collaboration with experimental colleagues\, we use a combination of quantitative microscopy\, image processing\, agent-based modeling\, and kinetic theory PDEs to uncover the mechanisms of emergent collective behaviors.
URL:https://www.ibs.re.kr/bimag/event/understanding-trade-offs-in-biological-information-processing/
LOCATION:KAIST E6-1 1501 Auditorium\, 291 Daehak-ro\, Yuseong-gu\, Daejeon\, 34141\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230501T160000
DTEND;TZID=Asia/Seoul:20230501T170000
DTSTAMP:20260429T221739
CREATED:20230409T052337Z
LAST-MODIFIED:20230414T024627Z
UID:7582-1682956800-1682960400@www.ibs.re.kr
SUMMARY:Understanding Trade-offs in Biological Information Processing
DESCRIPTION:High accuracy of major biological processes relies on the ability of the participating enzymatic molecules to preferentially select the correct substrate from a pool of chemically similar substrates by activating the so-called proofreading mechanisms. While the importance of such mechanisms is widely accepted\, it is still unclear how evolution has optimized biological systems with respect to their characteristic properties. We developed a comprehensive first-passage theoretical framework that allowed us to quantitatively investigate the trade-offs between the three properties of enzymatic systems: error\, speed\, noise\, and energy dissipation. Within this framework\, we simultaneously analyzed the speed and accuracy of several fundamental biological processes\, including DNA replication\, transcription\, tRNA charging\, and tRNA selection during the translation. The results indicate that the speed-accuracy trade-off is not always observed contrary to typical assumptions. However\, when the trade-off is present\, the biological systems tend to optimize the speed rather than the accuracy of the processes\, as long as the error level is tolerable. When systems function in a regime where no speed-accuracy trade-off is observed\, constraints due to energy dissipation in the proofreading play a key role. Our theory demonstrates a universal Pareto front in error-dissipation trade-off and shows how naturally selected kinetic parameters position their system close to this boundary. Our findings\, therefore\, provide a new system-level picture of how complex biological processes are able to function so fast with high accuracy and low dissipation.
URL:https://www.ibs.re.kr/bimag/event/uncovering-the-mechanisms-of-pattern-formation-and-emergent-collective-behaviors-in-myxobacteria/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20230327T160000
DTEND;TZID=Asia/Seoul:20230327T170000
DTSTAMP:20260429T221739
CREATED:20230323T064118Z
LAST-MODIFIED:20230323T064136Z
UID:7536-1679932800-1679936400@www.ibs.re.kr
SUMMARY:Sungwoong Cho\, HyperDeepONet: learning operator with complex target function space using the limited resources via hypernetwork
DESCRIPTION:Fast and accurate predictions for complex physical dynamics are a big challenge across various applications. Real-time prediction on resource-constrained hardware is even more crucial in the real-world problems. The deep operator network (DeepONet) has recently been proposed as a framework for learning nonlinear mappings between function spaces. However\, the DeepONet requires many parameters and has a high computational cost when learning operators\, particularly those with complex (discontinuous or non-smooth) target functions. In this study\, we propose HyperDeepONet\, which uses the expressive power of the hypernetwork to enable learning of a complex operator with smaller set of parameters. The DeepONet and its variant models can be thought of as a method of injecting the input function information into the target function. From this perspective\, these models can be viewed as a special case of HyperDeepONet. We analyze the complexity of DeepONet and conclude that HyperDeepONet needs relatively lower complexity to obtain the desired accuracy for operator learning. HyperDeepONet was successfully applied to various operator learning problems using low computational resources compared to other benchmarks.
URL:https://www.ibs.re.kr/bimag/event/2023-03-27-seminar/
LOCATION:B378 Seminar room\, IBS\, 55 Expo-ro Yuseong-gu\, Daejeon\, 34126\, Korea\, Republic of
CATEGORIES:Biomedical Mathematics Seminar
ORGANIZER;CN="Jae Kyoung Kim":MAILTO:jaekkim@kaist.ac.kr
END:VEVENT
END:VCALENDAR