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ינואר 01, 2013
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Date:06חמישייוני 2024הרצאה
Targeted Metabolic Analysis – Using an Out of the Box Approach
More information שעה 09:00 - 10:00מיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Dr. Alexander Brandis
Targeted Metabolomics Unitמארגן המחלקה לתשתיות מחקר מדעי החייםצרו קשר -
Date:06חמישייוני 2024סימפוזיונים
Physics Colloquium
More information שעה 11:15 - 12:30כותרת Emergent Quantum Phenomena in Crystalline Multilayer Grapheneמיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Prof. Long Ju
MITמארגן המחלקה לפיזיקה של חומר מעובהצרו קשר תקציר Show full text abstract about Condensed matter physics has witnessed emergent quantum phen...» Condensed matter physics has witnessed emergent quantum phenomena driven by electron correlation and topology. Such phenomena have been mostly observed in conventional crystalline materials where flat electronic bands are available. In recent years, moiré superlattices built upon two-dimensional (2D) materials emerged as a new platform to engineer and study electron correlation and topology. In this talk, I will introduce a family of synthetic quantum materials, based on crystalline multilayer graphene, as a new platform to engineer and study emergent phenomena driven by many-body interactions. This system hosts flat-bands in highly ordered conventional crystalline materials and dresses them with proximity effects enabled by rich structures in 2D van der Waals heterostructures. As a result, a rich spectrum of emergent phenomena including correlated insulators, spin/valley-polarized metals, integer and fractional quantum anomalous Hall effects, as well as superconductivities have been observed in our experiments. I will also discuss the implications of these observations for topological quantum computation.
References:
[1] Han, T., Lu, Z., Scuri, G. et al. Nat. Nanotechnol. 19, 181–187 (2024). [2] Han, T., Lu, Z., Scuri, G. et al. Nature 623, 41–47 (2023). [3] Han, T., Lu, Z., Yao, Y. et al. Science 384,647-651(2024). [4] Lu, Z., Han, T., Yao, Y. et al. Nature 626, 759–764 (2024). [5] Yang, J., Chen, G., Han, T. et al. Science, 375(6586), pp.1295-1299. (2022)
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Date:06חמישייוני 2024הרצאה
Vision and AI
More information שעה 12:15 - 13:15כותרת LIPVOICER: Generating Speech From Silent Videos Guided By Lip-Readingמיקום בניין יעקב זיסקינדמרצה Sharon Ganot
Bar-Ilan Universityמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתצרו קשר תקציר Show full text abstract about Lip-to-speech involves generating a natural-sounding speech ...» Lip-to-speech involves generating a natural-sounding speech synchronized with a soundless video of a person talking. Despite recent advances, current methods still cannot produce high-quality speech with high levels of intelligibility for challenging and realistic datasets. This talk presents LipVoicer, a novel method that generates high-quality speech, even for in-the-wild and rich datasets, by incorporating the text modality. Given a silent video, we first predict the spoken text using a pre-trained lip-reading network. We then condition a diffusion model on the video and use the extracted text through a classifier-guidance mechanism where a pre-trained automatic speech recognition (ASR) serves as the classifier. We demonstrate the effectiveness of LipVoicer through human evaluation, which shows that it produces more natural and synchronized speech signals than competing methods (demo page: https://lipvoicer.github.io). The presented LipVoicer is a joint work of Yochai Yemini, Aviv Shamsian, Lior Bracha, Sharon Gannot, and Ethan Fetaya.
Bio:
Sharon Gannot obtained his Ph.D. in electrical engineering from Tel-Aviv University, Israel, in 2000. He is a full professor in the Faculty of Engineering at Bar-Ilan University, Israel. He serves as a senior area chair for IEEE Transactions on Audio, Speech, and Language Processing, a member of the senior editorial board of IEEE Signal Processing Magazine, a member of the editorial board of IEEE SPS Education Center, and the chair of the IEEE Signal Processing Society Data Science Initiative. Previously, he was chair of the IEEE Audio and Acoustic Signal Processing Technical Committee in 2017–2018. He has also held other roles, such as the general co-chair of the 2010 International Workshop on Acoustic Signal Enhancement and the 2013 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics. He is the general co-chair of Interspeech 2024, which will be held in September in Greece. His research interests include statistical signal processing and machine learning in the audio processing domain. The methods he develops utilize multi-microphone and multi-modal information. Applications include speech enhancement, noise reduction, speaker separation and diarization, dereverberation, speaker localization, and tracking. Sharon Gannot is the recipient of the 2022 European Association for Signal Processing Group Technical Achievement Award and a Fellow of the IEEE.
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Date:06חמישייוני 2024הרצאה
Geometric Functional Analysis and Probability Seminar
More information שעה 13:30 - 14:30כותרת Charge fluctuations in the hierarchical Coulomb gasמיקום בניין יעקב זיסקינדמרצה Alon Nishry
TAUמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about The two-dimensional One-Component Plasma (OCP) is a Coulomb ...» The two-dimensional One-Component Plasma (OCP) is a Coulomb system (a point process) that consists of identical, electrically charged particles embedded in a uniform background of the opposite charge, interacting through a logarithmic potential, and kept at a fixed temperature. In the 90s, Jancovici, Lebowitz and Manificat discovered a law for the probabilities of observing large charge fluctuations in the OCP. Mathematically, this law has been fully proved only for one very special value of the temperature (corresponding to the Ginibre random matrix ensemble).
A few years ago, Chatterjee introduced a hierarchical version of the OCP, inspired by Dyson's hierarchical model of the Ising ferromagnet. We show that the JLM law holds for the hierarchical Coulomb model at any finite positive temperature.
Based on a joint work with Oren Yakir.
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Date:06חמישייוני 2024הרצאה
Insights from germline and somatic replication repair deficiency on cancer initiation and immunotherapy
More information שעה 14:00 - 15:00מיקום בניין ע"ש מקס ולילאן קנדיוטימרצה Prof. Uri Tabori
Head, Neuroonconcology program Division of Haematology/Oncology The Hospital for Sick Children Toronto, ON, Canadaמארגן המכון לחקר הטיפול בסרטן עש דואקצרו קשר -
Date:09ראשוןיוני 2024הרצאה
Special Guest Seminar
More information שעה 10:00 - 11:00כותרת Combined multimodal single-synapse profiling of synaptic activity, multiprotein composition, and translationמיקום בניין ארתור ורושל בלפר למחקר ביורפואימרצה Dr. Reuven (Beny) Falkovich
MIT Department of Biological Engineeringמארגן המחלקה לנוירוביולוגיה מולקולריתצרו קשר תקציר Show full text abstract about The analog computation at the chemical synapse that underlie...» The analog computation at the chemical synapse that underlies cognition depends on a highly compartmentalized, tightly regulated, and complex network of interactions between synaptic activity and hundreds of proteins and the mechanisms that regulate them. For a top-down study of how the network operates in concert, I present a modular, versatile approach for combined imaging of multiprotein composition, activation states, ion and neurotransmitter fluxes, and mRNA translation across the same individual synapses. I will show how this approach extends to other subcellular systems such as mitochondria. I will discuss the use of Bayesian network inference to extract biological insight from high-dimensional, multimodal synapse distributions. Finally, I will present applications of this approach to identify convergent molecular phenotypes across autism and schizophrenia-associated genes, and for an in-depth study of the complex synaptic response to genetic and chemical perturbations of GluN2A. -
Date:10שנייוני 2024סימפוזיונים
AI (R)Evolution in (Quantum) Chemistry and Physics
More information שעה 11:00 - 12:15כותרת Annual Pearlman Lectureמיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Prof. Alexandre Tkatchenko
Theoretical Chemical Physics, University of Luxembourgמארגן המחלקה לכימיה מולקולרית ולמדע חומריםדף בית צרו קשר תקציר Show full text abstract about Learning from data has led to paradigm shifts in a multitude...» Learning from data has led to paradigm shifts in a multitude of disciplines, including web, text and image search and generation, speech recognition, as well as bioinformatics. Can machine learning enable similar breakthroughs in understanding (quantum) dynamics of molecules and materials? This is an especially relevant question given that quantum mechanical predictions are now within experimental uncertainties for complex molecular systems (https://www.nature.com/articles/s41586-023-06587-3).
Aiming towards a unified machine learning (ML) model of molecular interactions in chemical space, I will discuss the potential and challenges for using ML techniques in chemistry and physics. ML methods can not only accurately estimate molecular properties of large datasets, but they can also lead to new insights into chemical similarity, aromaticity, reactivity, and molecular dynamics. For example, the combination of reliable molecular data with ML methods has enabled a fully quantitative simulation of protein dynamics in water (https://www.science.org/doi/full/10.1126/sciadv.adn4397). While the potential of machine learning for revealing insights into molecules and materials is high, I will conclude my talk by discussing the many remaining avenues for development. -
Date:10שנייוני 2024הרצאה
Midrasha on Groups Seminar
More information שעה 11:15 - 13:00כותרת Understanding infinitely presented groups using markings and applications to Hilbert–Schmidt stabilityמיקום בניין יעקב זיסקינדמרצה Alon Dogon
Weizmannמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about In this talk I will present a useful construction introduced...» In this talk I will present a useful construction introduced by Kassabov and Pak, called diagonal products. They arise naturally in the study of the space of marked groups, that is, the normal subgroups of a free group with the Chabauty topology. It turns out that diagonal products are extremely rich, and proved to be a useful tool for providing a full spectrum of various growth functions for groups. This includes answers to questions such as "How fast do Følner sets grow in an amenable group" and "How fast do residual chains grow in residually finite groups" etc. We will elaborate on a joint work with Arie Levit and Itamar Vigdorovich, where we give a general classification result for characters (á la Thoma) of many diagonal products. As a result, we deduce that there are uncountably many Hilbert–Schmidt stable groups, which are as unstable as one wants.
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Date:10שנייוני 2024הרצאה
Midrasha on Groups Seminar
More information שעה 11:15 - 13:00כותרת Understanding infinitely presented groups using markings and applications to Hilbert–Schmidt stabilityמיקום בניין יעקב זיסקינדמרצה Alon Dogon
Weizmannמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about In this talk I will present a useful construction introduced...» In this talk I will present a useful construction introduced by Kassabov and Pak, called diagonal products. They arise naturally in the study of the space of marked groups, that is, the normal subgroups of a free group with the Chabauty topology. It turns out that diagonal products are extremely rich, and proved to be a useful tool for providing a full spectrum of various growth functions for groups. This includes answers to questions such as "How fast do Følner sets grow in an amenable group" and "How fast do residual chains grow in residually finite groups" etc. We will elaborate on a joint work with Arie Levit and Itamar Vigdorovich, where we give a general classification result for characters (á la Thoma) of many diagonal products. As a result, we deduce that there are uncountably many Hilbert–Schmidt stable groups, which are as unstable as one wants.
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Date:10שנייוני 2024הרצאה
Foundations of Computer Science Seminar
More information שעה 11:15 - 12:15כותרת Fast and Cheap Asynchronous Construction of Small $k$-Dominating Setsמיקום בניין יעקב זיסקינדמרצה Yuval Emek
Technionמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתצרו קשר תקציר Show full text abstract about A $k$-dominating set ($k$-DS) is a node subset of distance a...» A $k$-dominating set ($k$-DS) is a node subset of distance at most $k$ from any node in the graph.
The task of constructing a small (i.e., existentially optimal) $k$-DS was suggested by Kutten and Peleg (Journal of Algorithms, 1998) as a useful primitive for distributed graph algorithms and received considerable attention ever since.
In the current paper, we advance the state-of-the-art of distributed small $k$-DS construction by presenting a randomized asynchronous CONGEST KT1 algorithm for this task that runs in $ ilde{O}( k^{2} )$ time and sends $ ilde{O}( n k )$ messages whp.
When $k leq polylog( n )$, we obtain the first asynchronous algorithm for a non-trivial distributed task whose communication cost is near-linear (in $n$).
The talk will be self contained.
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Date:10שנייוני 2024סימפוזיונים
Physics Colloquium
More information שעה 11:15 - 12:30כותרת OBSERVATION OF FRACTIONAL QUANTUM ANOMALOUS HALL EFFECTמיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Prof. Xiaodong Xu
University of Washington, Seattle, WAמארגן המחלקה לפיזיקה של חומר מעובהצרו קשר תקציר Show full text abstract about The interplay between spontaneous symmetry breaking and topo...» The interplay between spontaneous symmetry breaking and topology can result in exotic quantum states of matter. A celebrated example is the quantum anomalous Hall (QAH) effect, which exhibits an integer quantum Hall effect at zero magnetic field due to topologically nontrivial bands and intrinsic magnetism. In the presence of strong electron-electron interactions, fractional-QAH (FQAH) effect at zero magnetic field can emerge, which is a lattice analog of fractional quantum Hall effect without Landau level formation. In this talk, I will present experimental observation of FQAH effect in twisted MoTe2 bilayer, using combined magneto-optical and -transport measurements. In addition, we find an anomalous Hall state near the filling factor -1/2, whose behavior resembles that of the composite Fermi liquid phase in the half-filled lowest Landau level of a two-dimensional electron gas at high magnetic field. Direct observation of the FQAH and associated effects paves the way for researching charge fractionalization and anyonic statistics at zero magnetic field.
Reference
1. Observation of Fractionally Quantized Anomalous Hall Effect, Heonjoon Park et al., Nature, https://www.nature.com/articles/s41586-023-06536-0 (2023);
2. Signatures of Fractional Quantum Anomalous Hall States in Twisted MoTe2 Bilayer, Jiaqi Cai et al., Nature, https://www.nature.com/articles/s41586-023-06289-w (2023);
3. Programming Correlated Magnetic States via Gate Controlled Moiré Geometry, Eric Anderson et al., Science, https://www.science.org/doi/full/10.1126/science.adg4268 (2023).
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Date:10שנייוני 2024הרצאה
The Clore Center for Biological Physics- Special seminar
More information שעה 13:00 - 14:00כותרת Mixing Artificial and Natural Intelligence: From Statistical Mechanics to AI and Backמיקום בניין הפיזיקה ע"ש עדנה וק.ב. וייסמןמרצה Dr. Michael (Misha) Chertkov
University of Arizonaמארגן מרכז לפיזיקה ביולוגית עש קלורצרו קשר תקציר Show full text abstract about This presentation will outline recent evolution of AI method...» This presentation will outline recent evolution of AI methodologies, focusing on the emergence of Diffusion Models of AI inspired by non-equilibrium statistical mechanics, Transformers, and Reinforcement Learning. These innovations are revolutionizing our approach to reduced, Lagrangian turbulence modeling and are instrumental in formulating and solving new challenges, such as swimming navigation in chaotic environments.
More generally, attendees will gain insights into the synergy between AI and natural sciences and understand how this symbiosis is shaping the future of scientific research. This comprehensive vision is relevant to theoretical physicists, applied mathematicians, and computer scientists alike.
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Date:10שנייוני 2024הרצאה
Midrasha on Groups Seminar
More information שעה 14:15 - 16:00כותרת Topological overlap and homological connectivity of 2-complexesמיקום בניין יעקב זיסקינדמרצה Bharatram Rangarajan
HUJIמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about In this talk, we will prove the topological overlap property...» In this talk, we will prove the topological overlap property for 2-complexes that generalizes the Boros–Furedi theorem, following Yehudayoff's exposition of Gromov's method. The main idea is the notion of a folding map or obstruction, which also has a cohomological interpretation. We will further discuss homological connectivity of random 2-complexes based on a work of Linial and Meshulam.
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Date:13חמישייוני 2024כנסים
Annual Conference of the The Israeli Fermentation Society (2024)
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Ghil Jona -
Date:13חמישייוני 2024הרצאה
MSc defense seminar by Lior Peretz (Dr. Yonatan Stelzer Lab)
More information שעה 09:00 - 09:00כותרת Unraveling the Role of the Polycomb Repressive Complex in Gene Regulation During Early Mammalian Embryogenesisמיקום Ullman 102מרצה Ms. Lior Peretz
Dr. Yonatan Stelzer Labמארגן המחלקה לביולוגיה מולקולרית של התאצרו קשר -
Date:13חמישייוני 2024הרצאה
Special Guest Seminar
More information שעה 13:30 - 14:30כותרת Are black holes real – a mathematical perspectiveמיקום בניין יעקב זיסקינדמרצה Sergiu Klainerman
Princetonמארגן המחלקה למתמטיקהצרו קשר תקציר Show full text abstract about Given that black holes are by definition not directly observ...» Given that black holes are by definition not directly observable, physicists had to devise indirect techniques to test their reality. These efforts were recognized by 6 Nobel prizes in 2017 and 2020. The last three laureates included R. Penrose, cited for his famous singularity theorem, a real and strikingly beautiful mathematical proof. That recognition illustrates the role of mathematics in testing the reality of physical objects by proving or disproving specific mathematical conjectures. In my talk I will address the issue of the stability of Kerr black holes, another precise conjecture that can be decided by pure mathematical techniques.
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Date:13חמישייוני 2024הרצאה
Elucidating convergence and divergence of neural mechanisms: from genes to behavior
More information שעה 14:30 - 14:30מיקום אולם הרצאות ע"ש גרהרד שמידטמרצה Asaf Gat-Student Seminar-PhD Thesis Defense
Dr. Meital Oren Labמארגן המחלקה למדעי המוחצרו קשר תקציר Show full text abstract about The capacity of animals to respond to stimuli in their surro...» The capacity of animals to respond to stimuli in their surroundings is crucial for their survival. In mammals, complex evaluations of the environment require large numbers and different subtypes of neurons. The nematode C. elegans utilize its compact nervous system to process environmental cues and tune behavior. Integration of opposing spatial information and adaptation to distinct types of addictive substances are only a few challenges that require efficient and effective use of the worm’s compact nervous system. We describe how distinct environmental cues can converge onto common neural networks and molecular mechanisms but generate diverse neuronal and behavioral responses. Using a multidisciplinary approach, we completed several parallel aims, including the development of two novel research methods
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Date:13חמישייוני 2024הרצאה
Vision and AI
More information שעה 16:00 - 17:00כותרת Today’s “AI”-derived engineer-level models of the neural mechanisms of primate object perception, and tests of their application in non-invasive modulation of high level brain statesמרצה James DiCarlo
MITמארגן המחלקה למדעי המחשב ומתמטיקה שימושיתדף בית צרו קשר תקציר Show full text abstract about The human species is on a great scientific quest — to unders...» The human species is on a great scientific quest — to understand the neural mechanisms of human (primate) intelligence. Recent progress in multiple subfields of brain research suggests that key next steps in this quest will result from building real-world capable, systems-level network models that aim to abstract, emulate and explain the primate neural mechanisms underlying natural intelligent behavior. In this talk, I will briefly outline the story of how neuroscience, cognitive science and computer science (“AI”) converged to create specific, image-computable, deep neural network models intended to appropriately abstract, emulate and explain the mechanisms of primate core visual object identification and categorization. Based on a large body of primate neurophysiological and behavioral data, some of these network models are currently the leading (i.e. most accurate) scientific theories of the internal mechanisms of the primate ventral visual stream and how those mechanisms support the ability of humans and other primates to rapidly and accurately infer latent world content (e.g. object identity, position, pose, etc.) from the set of pixels (image) received under typical (brief) natural viewing.
While still far from complete, because these leading neuroscientific models are fully observable and machine-executable, they offer predictive and potential application power that the field’s prior conceptual models did not. I will describe two recent examples from our team. First, I will show that — relative to the gold standard of primate brains and minds — the leading models are both similarly sensitive to and similarly robust to adversarial attack at both their neural levels and their behavioral levels. Second, I will describe initial empirical tests of the closely related possibility of using such models to design spatial patterns of light energy on the retina (i.e. customized, synthetic images) to precisely, and non-invasively modulate neuronal activity deep in the primate brain. Consistent with model predictions, these tests reveal surprisingly strong and precise neural population effects. Besides being a tool for neuroscience, we see this as an exciting new application avenue of potential human clinical benefit.
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Date:16ראשוןיוני 202420חמישייוני 2024כנסים
Polymer Networks and Gels (PNG)
More information שעה 08:00 - 08:00מיקום מרכז כנסים על-שם דויד לופאטייושב ראש Nir Kampf -
Date:16ראשוןיוני 2024הרצאה
On Microbes and Mountains: Unraveling the Links Between Microbial Weathering and Large-Scale Surface Processes
More information שעה 11:00 - 11:00מיקום בניין משפחת זוסמןמרצה Michal Ben-Israel
University of Californiaמארגן המחלקה למדעי כדור הארץ וכוכבי הלכתצרו קשר תקציר Show full text abstract about Microorganisms play a crucial role in the weathering process...» Microorganisms play a crucial role in the weathering processes that transform rock into soil through chemical and physical mechanisms essential for nutrient cycling, nitrogen fixation, carbon storage, and organic matter decomposition. This intricate relationship between microbial life and landscapes forms the backbone of ecosystem dynamics and biogeochemical processes. Microbes influence rock weathering and soil production, adapting to their surroundings and creating distinct communities across various landscapes. These complex interactions and feedback mechanisms are pivotal to understanding the co-evolution of microbial communities and landscapes over time. However, existing research on microbial contributions to weathering and soil production has predominantly focused on relatively short timescales and small spatial scales. Understanding the interplay between the evolution of microbial communities and their role in weathering processes over geomorphic timescales within transient landscapes is important for a more complete understanding of how landscapes evolve as well as the impact of geomorphic changes on microbial community establishment and evolution.
The main objective of this study is to elucidate the long-term dynamics of microbial communities and their role in weathering processes over millennial timescales. To achieve this, we focused on recently deglaciated basins in the Eastern Sierra Nevada, CA, examining bacterial community composition in three phases of the weathering process: exposed rock at the surface, saprolite—the weathered rock found beneath soil, and soil. Sampling along an elevational transect, we collected 25 samples of rock, soil, and saprolite, and evaluated their bacterial composition using 16S rRNA and metagenomic sequencing.
Results show that both soil and saprolite samples exhibited diverse and similar microbial communities, indicating a developmental relationship between these habitats despite distinct geochemical compositions. In contrast, rock habitats are less diverse, and their composition resembles those of young deglaciated landscapes. Our findings point to a link between microbial community composition and rock-to-soil weathering processes, suggesting that the majority of weathering processes occur within the soil column (saprolite and soil), with exposed rock maintaining a steady state.
The stability of these microbial communities over extended timescales suggests a potentially significant role for microbial weathering in landscape evolution. This finding underscores the importance of considering microbial contributions in future geomorphic studies, as they may play a key role in shaping the Earth's surface. Moving forward, we plan on coupling a long-term, landscape-scale geomorphic perspective with 'omics approaches from microbial ecology to comprehensively understand the complex relationships between microbial life and landscapes, ultimately advancing our knowledge of ecosystem dynamics and health.