Article
Microscopy
Vivian S. Tong, T. Ben Britton
Summary: The paper describes TrueEBSD, an automatic postprocessing procedure for distortion correction with pixel scale precision, demonstrated on three case studies. By separating tilt and drift distortion components and fitting each to a distortion model, TrueEBSD enabled characterization of otherwise inaccessible microstructural features.
Article
Chemistry, Physical
Deobrat Singh, Rajeev Ahuja
Summary: The experimentally synthesized polypeptoid nanosheet crystal structure has brought significant advances in soft material imaging and designing biomimetic nanomaterials. By investigating the electronic structure and charge-transfer mechanism of the polypeptoid material, it was found that the material can effectively suppress the shuttle effect of LiPSs.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Multidisciplinary Sciences
Hiba Khaled Al-Jayyousi, Muhammad Sajjad, Kin Liao, Nirpendra Singh
Summary: The biphenylene sheet is proposed as an anchoring material for lithium-sulfur batteries, showing superior conductivity, porosity, and strong anchoring ability. Defect engineering significantly improves the binding strength between biphenylene and LiPSs, suppressing the shuttle effect.
SCIENTIFIC REPORTS
(2022)
Article
Materials Science, Multidisciplinary
Lihong Song, Mingang Zhang, Xiangyu Cao, Jin Guo
Summary: This study employed first-principles calculation to investigate the potential application of VX (X = S, Se) as an anchoring material for Li-S batteries. The results suggest that VS and VSe may act as excellent anchoring materials for high-efficiency Li-S batteries.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Communication
Jing Meng, Yu-Peng Lin, Hui-Ju Tsai
Summary: This article investigates the exercise of data and spatial agency by digital maps, using the case of the environmental mobile mapping application water refill map (WRM) in Taiwan. The study examines how the app leverages the power of digital mapping to encourage participation in environmental activities and argues that digital maps enable placemaking at cognitive and hermeneutic levels, transforming closed spaces into public ones. It also explores the contestation and negotiation between agency and structure, apps and infrastructural platforms, collective action and individual power, and environmentalism and commercialism in this digital environmental activism.
NEW MEDIA & SOCIETY
(2023)
Article
Neurosciences
Ross D. Markello, Bratislav Misic
Summary: The study evaluated the performance of ten different null frameworks in statistical analysis of neuroimaging data. Results showed that null models that preserved spatial autocorrelation produced more realistic, conservative statistical estimates, but still had elevated false positive rates and variable performance across different analyses.
Article
Environmental Sciences
Cristina Galvan, Araceli Puente, Jose A. Juanes
Summary: This study identified ecotopes and anthrotopes in an estuary using a hierarchical approach that integrated information about abiotic and biologically meaningful variables, estimating the potential impacts of human pressures on species and providing flexible tools for conservation and research.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Multidisciplinary Sciences
Max Falkenberg, James A. A. Coleman, Sam Dobson, David J. J. Hickey, Louie Terrill, Alberto Ciacci, Belvin Thomas, Arunashis Sau, Fu Siong Ng, Jichao Zhao, Nicholas S. S. Peters, Kim Christensen
Summary: This paper introduces a computational method to identify atrial regions susceptible to micro-anatomical reentry in atrial fibrillation (AF). The method models the accumulation of electrically insulating interstitial fibrosis using percolation-like phenomena on spatial networks. The results suggest that thin and convex regions of the atria are more likely to facilitate micro-reentry, and strong longitudinal fibre coupling can suppress this process.
Article
Green & Sustainable Science & Technology
E. Hallstrom, J. Davis, N. Hakansson, S. Ahlgren, A. Akesson, A. Wolk, U. Sonesson
Summary: The environmental impact of Swedish diets exceeds planetary boundaries, with animal-based foods contributing more to greenhouse gas emissions, cropland use, and nitrogen and phosphorus application, while plant-based and discretionary foods contribute more to consumptive water use and extinction rate. Reducing consumption of red meat, dairy, fresh fruit, and coffee can help reduce environmental impact.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Multidisciplinary Sciences
Heather Tallis, Joe Fargione, Edward Game, Rob McDonald, Leandro Baumgarten, Nirmal Bhagabati, Rane Cortez, Bronson Griscom, Jonathan Higgins, Christina M. Kennedy, Joe Kiesecker, Timm Kroeger, Trina Leberer, Jennifer McGowan, Lisa Mandle, Yuta J. Masuda, Scott A. Morrison, Sally Palmer, Rebecca Shirer, Priya Shyamsundar, Nicholas H. Wolff, Hugh P. Possingham
Summary: Spatial prioritization is crucial in conservation planning but many current methods have limitations. The introduction of spatial action mapping offers a solution by providing a spatially explicit view. Through seven case examples, it is demonstrated that this method can be applied across various scales to support decision-making on conservation actions and benefits efficiently.
ANNALS OF THE NEW YORK ACADEMY OF SCIENCES
(2021)
Article
Chemistry, Multidisciplinary
V. Lakshmi Prasanna, Dhakshnamoorthi Harikaran, Dror Avisar, R. Vijayaraghavan
Summary: Inorganic oxide materials such as TiO2 and ZnO have been extensively studied for environmental remediation, while the use of inorganic solid oxidants such as metal peroxides for this purpose remains unexplored. This study explores the synthesis and characterization of peroxides of Zn, Mg, and Ba and their photocatalytic activity. BaO2 is identified as a potential photocatalyst with higher activity than ZnO, and the mechanisms of reactive oxygen species (ROS) generation and dye degradation are elucidated.
Article
Chemistry, Analytical
Muhammad Rehan, Andrew G. Yeo, Muhammad Uzair Yousuf, Ebubekir Avci
Summary: This paper presents the design and development of an anchoring mechanism and actuation system to hold a capsule endoscope in place within the small intestine. The experiments show that the proposed design can anchor the capsule at the target site and resist peristaltic forces, allowing for a better examination of the intestine.
Article
Chemistry, Physical
H. T. Jeong, W. J. Kim
Summary: Through systematic analysis, constitutive deformation equations were determined for high-entropy alloys, leading to the calculation and construction of deformation mechanism maps and processing maps. These maps are useful for predicting optimal hot working conditions and identifying deformation mechanisms.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Neurosciences
Lukas Kunz, Armin Brandt, Peter C. Reinacher, Bernhard P. Staresina, Eric T. Reifenstein, Christoph T. Weidemann, Nora A. Herweg, Ansh Patel, Melina Tsitsiklis, Richard Kempter, Michael J. Kahana, Andreas Schulze-Bonhage, Joshua Jacobs
Summary: The study identified neurons in the human brain that provide a neural code for egocentric spatial maps, which play a key role in navigation and memory recall.
Article
Biochemistry & Molecular Biology
William de Cothi, Nils Nyberg, Eva-Maria Griesbauer, Carole Ghaname, Fiona Zisch, Julie M. Lefort, Lydia Fletcher, Coco Newton, Sophie Renaudineau, Daniel Bendor, Roddy Grieves, Eleonore Duvelle, Caswell Barry, Hugo J. Spiers
Summary: By studying the behavior of humans, rats, and simulated reinforcement learning agents, we found that they exhibit similar dynamics in spatial navigation. These findings contribute to refining navigation models and uncovering shared mechanisms underlying behavior.
Article
Multidisciplinary Sciences
Caitlin S. Mallory, Kiah Hardcastle, Malcolm G. Campbell, Alexander Attinger, Isabel I. C. Low, Jennifer L. Raymond, Lisa M. Giocomo
Summary: Neural circuits in the medial temporal lobe construct a map-like representation of space that supports navigation by integrating multiple sensory cues and cues related to the individual's movement through the environment. The medial entorhinal cortex (MEC) encodes three-dimensional head movement, eye position, and velocity, alongside other self-motion signals in individual neurons, such as body position, running speed, and azimuthal head direction.
NATURE COMMUNICATIONS
(2021)
Editorial Material
Biochemistry & Molecular Biology
Mark H. Plitt, Lisa M. Giocomo
Summary: The recent study using new holographic optogenetic stimulation technology provides direct evidence that hippocampal place cell activity is sufficient to drive memory and navigation-related behaviors.
Article
Neurosciences
Mark H. Plitt, Lisa M. Giocomo
Summary: The hippocampus contains neural representations capable of supporting declarative memory, with place cells firing in specific locations in different environments. Through large-scale in vivo recordings, it was found that hippocampal remapping across contexts can be precisely predicted by the animal's experience and approximates optimal probabilistic inference. This suggests that place cell remapping allows animals to identify their physical location and estimate the identity of the environment optimally.
NATURE NEUROSCIENCE
(2021)
Review
Neurosciences
Marielena Sosa, Lisa M. Giocomo
Summary: The ability to remember and navigate to spatial locations associated with rewards, such as food or safety, is crucial for survival. The hippocampus and entorhinal cortex play key roles in storing and retrieving reward-related information in the brain by representing physical and mental space as a series of states. This proposal is supported by recent advances in both experimental and theoretical neuroscience, aiming to provide an integrated framework for understanding navigation to reward as a fundamental feature of many cognitive processes.
NATURE REVIEWS NEUROSCIENCE
(2021)
Article
Neurosciences
Isabel I. C. Low, Alex H. Williams, Malcolm G. Campbell, Scott W. Linderman, Lisa M. Giocomo
Summary: Neurons in the medial entorhinal cortex exhibit flexibility in neural coding by altering firing properties in response to environmental changes, supporting navigation and memory. Rapid and reversible transitions were observed between multiple spatial maps, synchronized across hundreds of neurons and correlated with changes in running speed. Despite widespread changes in spatial coding, remapping was characterized by a translation along a single dimension in population-level activity space, enabling simple decoding strategies.
Article
Cell Biology
Malcolm G. Campbell, Alexander Attinger, Samuel A. Ocko, Surya Ganguli, Lisa M. Giocomo
Summary: During navigation, animals utilize path integration and landmarks to estimate their position, with different brain areas playing specialized roles in cue integration. The medial entorhinal cortex (MEC) has a greater influence of path integration on position estimates compared to other cortical areas, and conflicts between path integration and landmarks trigger remapping more readily in MEC. Lowered visual contrast only increases the influence of path integration on position estimates in MEC.
Editorial Material
Multidisciplinary Sciences
Isabel I. C. Low, Lisa M. Giocomo
Editorial Material
Neurosciences
Isabel I. C. Low, Lisa M. Giocomo
Summary: Pettit, Yuan, and Harvey discovered that hippocampal spatial maps degrade when mice voluntarily disengage from a navigation task, even without changes in sensory or self-motion cues. This suggests that internal state might play an active role in supporting navigational coding and spatial memory.
NATURE NEUROSCIENCE
(2022)
Editorial Material
Veterinary Sciences
Alexander Gonzalez, Lisa M. Giocomo
Summary: A new study combines a novel behavioral paradigm in rats and humans with reinforcement learning to infer shared computations for goal-directed navigation.
Article
Neurosciences
Ben Sorscher, Gabriel C. Mel, Samuel A. Ocko, Lisa M. Giocomo, Surya Ganguli
Summary: The discovery of entorhinal grid cells has sparked interest in understanding the emergence of hexagonal firing fields in neural circuits and their computational significance. In this study, we demonstrate that hexagonal grids can arise in neural networks trained for path integration under biologically plausible constraints. We also provide a unified theory for the prevalence of hexagonal grids in path-integrator circuits. Our trained networks offer mechanistic hypotheses and capture biological variability better than hand-designed models. Additionally, we develop methods to analyze the connectome and activity maps of our networks, revealing fundamental mechanisms underlying path integration in a generalizable manner.
Article
Biochemistry & Molecular Biology
Linlin Z. Fan, Doo Kyung Kim, Joshua H. Jennings, He Tian, Peter Y. Wang, Charu Ramakrishnan, Sawyer Randles, Yanjun Sun, Elina Thadhani, Yoon Seok Kim, Sean Quirin, Lisa Giocomo, Adam E. Cohen, Karl Deisseroth
Summary: Learning-induced modifications of synaptic and circuit properties storing information in mammals have been unclear. This study used genetically targeted voltage imaging and optogenetic activation to show that specific optogenetic activation of CA1 cells induced stable representations of specific places. It was found that presynaptic CA2/3 cells were required for inducing plasticity in CA1, and during the induction of place fields in single CA1 cells, synaptic input from CA2/3 onto these same cells was potentiated. These findings reveal the synaptic mechanisms underlying hippocampal behavioral timescale plasticity during learning and memory in behaving mammals.
Article
Neurosciences
Emily A. Aery Jones, Lisa M. Giocomo
Summary: The brain represents behaviorally relevant information through the firing of individual neurons and ensembles of neurons. Ensembles in the hippocampus and associated cortical regions support navigation through various types of codes, including single cell codes, population codes, time-compressed sequences, behavioral sequences, and engrams. Traditional definitions of ensembles can constrain or expand potential analyses, and coding can change at the ensemble level while single cell codes remain intact. Broader ensemble definitions are needed to better understand the complexity of the brain.
CURRENT OPINION IN NEUROBIOLOGY
(2023)
Article
Multidisciplinary Sciences
Yanjun Sun, Lisa M. Giocomo
Summary: This study reveals that a subset of neurons in the hippocampus of mice encode drug-associated contextual information, providing insight into how drug abuse alters hippocampal circuitry to encode drug-context associations.
NATURE COMMUNICATIONS
(2022)
Article
Biochemical Research Methods
S. Wenceslao Evans, Dong-Qing Shi, Mariya Chavarha, Mark H. Plitt, Jiannis Taxidis, Blake Madruga, Jiang Lan Fan, Fuu-Jiun Hwang, Siri C. van Keulen, Carl-Mikael Suomivuori, Michelle M. Pang, Sharon Su, Sungmoo Lee, Yukun A. Hao, Guofeng Zhang, Dongyun Jiang, Lagnajeet Pradhan, Richard H. Roth, Yu Liu, Conor C. Dorian, Austin L. Reese, Adrian Negrean, Attila Losonczy, Christopher D. Makinson, Sui Wang, Thomas R. Clandinin, Ron O. Dror, Jun B. Ding, Na Ji, Peyman Golshani, Lisa M. Giocomo, Guo-Qiang Bi, Michael Z. Lin
Summary: By inverting the fluorescence-voltage relationship, the photostability of ASAP family genetically encoded voltage indicators (GEVIs) has been enhanced. Two improved GEVIs, ASAP4b and ASAP4e, enable single-trial detection and recording in standard one- and two-photon microscopes with better temporal resolution. They can simultaneously detect voltage and calcium signals and extend the duration of voltage recordings.
Article
Biology
Isabel I. C. Low, Lisa M. Giocomo, Alex H. Williams
Summary: Researchers found that neurons in navigational brain regions can change their firing patterns in response to changing contextual factors while preserving local computations. By training neural network models to track position and report transiently-cued context changes in simple environments, they showed that the activity patterns are similar to population-wide remapping in the navigational brain region. Furthermore, the models' solution generalizes to more complex navigation and inference tasks.