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  1. Article ; Online: A Physics-Inspired Mechanistic Model of Migratory Movement Patterns in Birds.

    Revell, Christopher / Somveille, Marius

    Scientific reports

    2017  Volume 7, Issue 1, Page(s) 9870

    Abstract: In this paper, we introduce a mechanistic model of migratory movement patterns in birds, inspired by ideas and methods from physics. Previous studies have shed light on the factors influencing bird migration but have mainly relied on statistical ... ...

    Abstract In this paper, we introduce a mechanistic model of migratory movement patterns in birds, inspired by ideas and methods from physics. Previous studies have shed light on the factors influencing bird migration but have mainly relied on statistical correlative analysis of tracking data. Our novel method offers a bottom up explanation of population-level migratory movement patterns. It differs from previous mechanistic models of animal migration and enables predictions of pathways and destinations from a given starting location. We define an environmental potential landscape from environmental data and simulate bird movement within this landscape based on simple decision rules drawn from statistical mechanics. We explore the capacity of the model by qualitatively comparing simulation results to the non-breeding migration patterns of a seabird species, the Black-browed Albatross (Thalassarche melanophris). This minimal, two-parameter model was able to capture remarkably well the previously documented migration patterns of the Black-browed Albatross, with the best combination of parameter values conserved across multiple geographically separate populations. Our physics-inspired mechanistic model could be applied to other bird and highly-mobile species, improving our understanding of the relative importance of various factors driving migration and making predictions that could be useful for conservation.
    MeSH term(s) Algorithms ; Animal Migration ; Animals ; Birds ; Environment ; Geography ; Models, Theoretical
    Language English
    Publishing date 2017-08-29
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-017-09270-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Neurophysiological Evidence for Cognitive Map Formation during Sequence Learning.

    Stiso, Jennifer / Lynn, Christopher W / Kahn, Ari E / Rangarajan, Vinitha / Szymula, Karol P / Archer, Ryan / Revell, Andrew / Stein, Joel M / Litt, Brian / Davis, Kathryn A / Lucas, Timothy H / Bassett, Dani S

    eNeuro

    2022  Volume 9, Issue 2

    Abstract: Humans deftly parse statistics from sequences. Some theories posit that humans learn these statistics by forming cognitive maps, or underlying representations of the latent space which links items in the sequence. Here, an item in the sequence is a node, ...

    Abstract Humans deftly parse statistics from sequences. Some theories posit that humans learn these statistics by forming cognitive maps, or underlying representations of the latent space which links items in the sequence. Here, an item in the sequence is a node, and the probability of transitioning between two items is an edge. Sequences can then be generated from walks through the latent space, with different spaces giving rise to different sequence statistics. Individual or group differences in sequence learning can be modeled by changing the time scale over which estimates of transition probabilities are built, or in other words, by changing the amount of temporal discounting. Latent space models with temporal discounting bear a resemblance to models of navigation through Euclidean spaces. However, few explicit links have been made between predictions from Euclidean spatial navigation and neural activity during human sequence learning. Here, we use a combination of behavioral modeling and intracranial encephalography (iEEG) recordings to investigate how neural activity might support the formation of space-like cognitive maps through temporal discounting during sequence learning. Specifically, we acquire human reaction times from a sequential reaction time task, to which we fit a model that formulates the amount of temporal discounting as a single free parameter. From the parameter, we calculate each individual's estimate of the latent space. We find that neural activity reflects these estimates mostly in the temporal lobe, including areas involved in spatial navigation. Similar to spatial navigation, we find that low-dimensional representations of neural activity allow for easy separation of important features, such as modules, in the latent space. Lastly, we take advantage of the high temporal resolution of iEEG data to determine the time scale on which latent spaces are learned. We find that learning typically happens within the first 500 trials, and is modulated by the underlying latent space and the amount of temporal discounting characteristic of each participant. Ultimately, this work provides important links between behavioral models of sequence learning and neural activity during the same behavior, and contextualizes these results within a broader framework of domain general cognitive maps.
    MeSH term(s) Cognition/physiology ; Humans ; Learning/physiology ; Reaction Time ; Spatial Navigation/physiology ; Temporal Lobe/physiology
    Language English
    Publishing date 2022-03-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2800598-3
    ISSN 2373-2822 ; 2373-2822
    ISSN (online) 2373-2822
    ISSN 2373-2822
    DOI 10.1523/ENEURO.0361-21.2022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Cell surface fluctuations regulate early embryonic lineage sorting.

    Yanagida, Ayaka / Corujo-Simon, Elena / Revell, Christopher K / Sahu, Preeti / Stirparo, Giuliano G / Aspalter, Irene M / Winkel, Alex K / Peters, Ruby / De Belly, Henry / Cassani, Davide A D / Achouri, Sarra / Blumenfeld, Raphael / Franze, Kristian / Hannezo, Edouard / Paluch, Ewa K / Nichols, Jennifer / Chalut, Kevin J

    Cell

    2022  Volume 185, Issue 7, Page(s) 1258

    Language English
    Publishing date 2022-04-01
    Publishing country United States
    Document type Published Erratum
    ZDB-ID 187009-9
    ISSN 1097-4172 ; 0092-8674
    ISSN (online) 1097-4172
    ISSN 0092-8674
    DOI 10.1016/j.cell.2022.03.015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Cell surface fluctuations regulate early embryonic lineage sorting.

    Yanagida, Ayaka / Corujo-Simon, Elena / Revell, Christopher K / Sahu, Preeti / Stirparo, Giuliano G / Aspalter, Irene M / Winkel, Alex K / Peters, Ruby / De Belly, Henry / Cassani, Davide A D / Achouri, Sarra / Blumenfeld, Raphael / Franze, Kristian / Hannezo, Edouard / Paluch, Ewa K / Nichols, Jennifer / Chalut, Kevin J

    Cell

    2022  Volume 185, Issue 5, Page(s) 777–793.e20

    Abstract: In development, lineage segregation is coordinated in time and space. An important example is the mammalian inner cell mass, in which the primitive endoderm (PrE, founder of the yolk sac) physically segregates from the epiblast (EPI, founder of the fetus) ...

    Abstract In development, lineage segregation is coordinated in time and space. An important example is the mammalian inner cell mass, in which the primitive endoderm (PrE, founder of the yolk sac) physically segregates from the epiblast (EPI, founder of the fetus). While the molecular requirements have been well studied, the physical mechanisms determining spatial segregation between EPI and PrE remain elusive. Here, we investigate the mechanical basis of EPI and PrE sorting. We find that rather than the differences in static cell surface mechanical parameters as in classical sorting models, it is the differences in surface fluctuations that robustly ensure physical lineage sorting. These differential surface fluctuations systematically correlate with differential cellular fluidity, which we propose together constitute a non-equilibrium sorting mechanism for EPI and PrE lineages. By combining experiments and modeling, we identify cell surface dynamics as a key factor orchestrating the correct spatial segregation of the founder embryonic lineages.
    MeSH term(s) Animals ; Blastocyst/metabolism ; Cell Differentiation/physiology ; Cell Lineage/physiology ; Cell Membrane/metabolism ; Embryo, Mammalian/metabolism ; Embryonic Development ; Endoderm/metabolism ; Mammals ; Mice ; Protein Transport
    Language English
    Publishing date 2022-02-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 187009-9
    ISSN 1097-4172 ; 0092-8674
    ISSN (online) 1097-4172
    ISSN 0092-8674
    DOI 10.1016/j.cell.2022.01.022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Environmental plastics in the context of UV radiation, climate change, and the Montreal Protocol.

    Jansen, Marcel A K / Andrady, Anthony L / Barnes, Paul W / Busquets, Rosa / Revell, Laura E / Bornman, Janet F / Aucamp, Pieter J / Bais, Alkiviadis F / Banaszak, Anastazia T / Bernhard, Germar H / Bruckman, Laura S / Häder, Donat-P / Hanson, Mark L / Heikkilä, Anu M / Hylander, Samuel / Lucas, Robyn M / Mackenzie, Roy / Madronich, Sasha / Neale, Patrick J /
    Neale, Rachel E / Olsen, Catherine M / Ossola, Rachele / Pandey, Krishna K / Petropavlovskikh, Irina / Robinson, Sharon A / Robson, T Matthew / Rose, Kevin C / Solomon, Keith R / Sulbæk Andersen, Mads P / Sulzberger, Barbara / Wallington, Timothy J / Wang, Qing-Wei / Wängberg, Sten-Åke / White, Christopher C / Young, Antony R / Zepp, Richard G / Zhu, Liping

    Global change biology

    2024  Volume 30, Issue 4, Page(s) e17279

    Abstract: There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such ... ...

    Abstract There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.
    MeSH term(s) Ultraviolet Rays/adverse effects ; Climate Change ; Solar Energy ; Environmental Pollution ; Weather
    Language English
    Publishing date 2024-02-01
    Publishing country England
    Document type Letter
    ZDB-ID 1281439-8
    ISSN 1365-2486 ; 1354-1013
    ISSN (online) 1365-2486
    ISSN 1354-1013
    DOI 10.1111/gcb.17279
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Plastics in the environment in the context of UV radiation, climate change and the Montreal Protocol: UNEP Environmental Effects Assessment Panel, Update 2023.

    Jansen, Marcel A K / Andrady, Anthony L / Bornman, Janet F / Aucamp, Pieter J / Bais, Alkiviadis F / Banaszak, Anastazia T / Barnes, Paul W / Bernhard, Germar H / Bruckman, Laura S / Busquets, Rosa / Häder, Donat-P / Hanson, Mark L / Heikkilä, Anu M / Hylander, Samuel / Lucas, Robyn M / Mackenzie, Roy / Madronich, Sasha / Neale, Patrick J / Neale, Rachel E /
    Olsen, Catherine M / Ossola, Rachele / Pandey, Krishna K / Petropavlovskikh, Irina / Revell, Laura E / Robinson, Sharon A / Robson, T Matthew / Rose, Kevin C / Solomon, Keith R / Andersen, Mads P Sulbæk / Sulzberger, Barbara / Wallington, Timothy J / Wang, Qing-Wei / Wängberg, Sten-Åke / White, Christopher C / Young, Antony R / Zepp, Richard G / Zhu, Liping

    Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology

    2024  Volume 23, Issue 4, Page(s) 629–650

    Abstract: This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The ... ...

    Abstract This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.
    MeSH term(s) Humans ; Plastics/toxicity ; Ecosystem ; Ultraviolet Rays ; Climate Change ; Water Pollutants, Chemical/analysis
    Chemical Substances Plastics ; Water Pollutants, Chemical
    Language English
    Publishing date 2024-03-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2072584-X
    ISSN 1474-9092 ; 1474-905X
    ISSN (online) 1474-9092
    ISSN 1474-905X
    DOI 10.1007/s43630-024-00552-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Success rates and immunologic responses of autogenic, allogenic, and xenogenic treatments to repair articular cartilage defects.

    Revell, Christopher M / Athanasiou, Kyriacos A

    Tissue engineering. Part B, Reviews

    2008  Volume 15, Issue 1, Page(s) 1–15

    Abstract: This review examines current approaches available for articular cartilage repair, not only in terms of their regeneration potential, but also as a function of immunologic response. Autogenic repair techniques, including osteochondral plug transplantation, ...

    Abstract This review examines current approaches available for articular cartilage repair, not only in terms of their regeneration potential, but also as a function of immunologic response. Autogenic repair techniques, including osteochondral plug transplantation, chondrocyte implantation, and microfracture, are the most widely accepted clinical treatment options due to the lack of immunogenic reactions, but only moderate graft success rates have been reported. Although suspended allogenic chondrocytes are shown to evoke an immune response upon implantation, allogenic osteochondral plugs and tissue-engineered grafts using allogenic chondrocytes exhibit a tolerable immunogenic response. Additionally, these repair techniques produce neotissue with success rates approaching those of currently available autogenic repair techniques, while simultaneously obviating their major hindrance of donor tissue scarcity. To date, limited research has been performed with xenogenic tissue, although several studies demonstrate the potential for its long-term success. This article focuses on the various treatment options for cartilage repair and their associated success rates and immunologic responses.
    MeSH term(s) Animals ; Cartilage Diseases/pathology ; Cartilage Diseases/surgery ; Cartilage, Articular/transplantation ; Chickens ; Chondrocytes/transplantation ; Horses ; Humans ; Rabbits ; Rats ; Tissue Engineering/methods ; Transplantation/methods ; Transplantation, Heterologous/methods ; Transplantation, Homologous/methods ; Treatment Outcome
    Language English
    Publishing date 2008-12-08
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 2420584-9
    ISSN 1937-3376 ; 1937-3368
    ISSN (online) 1937-3376
    ISSN 1937-3368
    DOI 10.1089/ten.teb.2008.0189
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Notch controls the cell cycle to define leader versus follower identities during collective cell migration.

    Alhashem, Zain / Feldner-Busztin, Dylan / Revell, Christopher / Alvarez-Garcillan Portillo, Macarena / Camargo-Sosa, Karen / Richardson, Joanna / Rocha, Manuel / Gauert, Anton / Corbeaux, Tatianna / Milanetto, Martina / Argenton, Francesco / Tiso, Natascia / Kelsh, Robert N / Prince, Victoria E / Bentley, Katie / Linker, Claudia

    eLife

    2022  Volume 11

    Abstract: Coordination of cell proliferation and migration is fundamental for life, and its dysregulation has catastrophic consequences, such as cancer. How cell cycle progression affects migration, and vice versa, remains largely unknown. We address these ... ...

    Abstract Coordination of cell proliferation and migration is fundamental for life, and its dysregulation has catastrophic consequences, such as cancer. How cell cycle progression affects migration, and vice versa, remains largely unknown. We address these questions by combining in silico modelling and in vivo experimentation in the zebrafish trunk neural crest (TNC). TNC migrate collectively, forming chains with a leader cell directing the movement of trailing followers. We show that the acquisition of migratory identity is autonomously controlled by Notch signalling in TNC. High Notch activity defines leaders, while low Notch determines followers. Moreover, cell cycle progression is required for TNC migration and is regulated by Notch. Cells with low Notch activity stay longer in G
    MeSH term(s) Animals ; Cell Division ; Cell Movement/physiology ; Neural Crest ; Signal Transduction ; Zebrafish/physiology
    Language English
    Publishing date 2022-04-19
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.73550
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Chondroitinase ABC treatment results in greater tensile properties of self-assembled tissue-engineered articular cartilage.

    Natoli, Roman M / Revell, Christopher M / Athanasiou, Kyriacos A

    Tissue engineering. Part A

    2009  Volume 15, Issue 10, Page(s) 3119–3128

    Abstract: Collagen content and tensile properties of engineered articular cartilage have remained inferior to glycosaminoglycan (GAG) content and compressive properties. Based on a cartilage explant study showing greater tensile properties after chondroitinase ABC ...

    Abstract Collagen content and tensile properties of engineered articular cartilage have remained inferior to glycosaminoglycan (GAG) content and compressive properties. Based on a cartilage explant study showing greater tensile properties after chondroitinase ABC (C-ABC) treatment, C-ABC as a strategy for cartilage tissue engineering was investigated. A scaffold-less approach was employed, wherein chondrocytes were seeded into non-adherent agarose molds. C-ABC was used to deplete GAG from constructs 2 weeks after initiating culture, followed by 2 weeks culture post-treatment. Staining for GAG and type I, II, and VI collagen and transmission electron microscopy were performed. Additionally, quantitative total collagen, type I and II collagen, and sulfated GAG content were measured, and compressive and tensile mechanical properties were evaluated. At 4 wks, C-ABC treated construct ultimate tensile strength and tensile modulus increased 121% and 80% compared to untreated controls, reaching 0.5 and 1.3 MPa, respectively. These increases were accompanied by increased type II collagen concentration, without type I collagen. As GAG returned, compressive stiffness of C-ABC treated constructs recovered to be greater than 2 wk controls. C-ABC represents a novel method for engineering functional articular cartilage by departing from conventional anabolic approaches. These results may be applicable to other GAG-producing tissues functioning in a tensile capacity, such as the musculoskeletal fibrocartilages.
    MeSH term(s) Biomechanical Phenomena ; Cartilage, Articular/cytology ; Cartilage, Articular/drug effects ; Cartilage, Articular/metabolism ; Cartilage, Articular/ultrastructure ; Chondroitin ABC Lyase/metabolism ; Chondroitin ABC Lyase/pharmacology ; Enzyme-Linked Immunosorbent Assay ; Glycosaminoglycans/metabolism ; Microscopy, Electron, Transmission ; Tensile Strength/drug effects ; Tissue Engineering/methods
    Chemical Substances Glycosaminoglycans ; Chondroitin ABC Lyase (EC 4.2.2.20)
    Language English
    Publishing date 2009-04-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2420582-5
    ISSN 1937-335X ; 1937-3341
    ISSN (online) 1937-335X
    ISSN 1937-3341
    DOI 10.1089/ten.TEA.2008.0478
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Cell surface fluctuations regulate early embryonic lineage sorting

    Yanagida, Ayaka / Corujo-Simon, Elena / Revell, Christopher K. / Sahu, Preeti / Stirparo, Giuliano G. / Aspalter, Irene M. / Winkel, Alex K. / Peters, Ruby / De Belly, Henry / Cassani, Davide A.D. / Achouri, Sarra / Blumenfeld, Raphael / Franze, Kristian / Hannezo, Edouard / Paluch, Ewa K. / Nichols, Jennifer / Chalut, Kevin J.

    Cell. 2022 Mar. 03, v. 185, no. 5

    2022  

    Abstract: In development, lineage segregation is coordinated in time and space. An important example is the mammalian inner cell mass, in which the primitive endoderm (PrE, founder of the yolk sac) physically segregates from the epiblast (EPI, founder of the fetus) ...

    Abstract In development, lineage segregation is coordinated in time and space. An important example is the mammalian inner cell mass, in which the primitive endoderm (PrE, founder of the yolk sac) physically segregates from the epiblast (EPI, founder of the fetus). While the molecular requirements have been well studied, the physical mechanisms determining spatial segregation between EPI and PrE remain elusive. Here, we investigate the mechanical basis of EPI and PrE sorting. We find that rather than the differences in static cell surface mechanical parameters as in classical sorting models, it is the differences in surface fluctuations that robustly ensure physical lineage sorting. These differential surface fluctuations systematically correlate with differential cellular fluidity, which we propose together constitute a non-equilibrium sorting mechanism for EPI and PrE lineages. By combining experiments and modeling, we identify cell surface dynamics as a key factor orchestrating the correct spatial segregation of the founder embryonic lineages.
    Keywords endoderm ; fetus ; mammals ; yolk sac
    Language English
    Dates of publication 2022-0303
    Size p. 777-793.e20.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 187009-9
    ISSN 1097-4172 ; 0092-8674
    ISSN (online) 1097-4172
    ISSN 0092-8674
    DOI 10.1016/j.cell.2022.01.022
    Database NAL-Catalogue (AGRICOLA)

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