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Nicholas Tolley

@ntolley.bsky.social
169 followers 277 following 21 posts

Postdoc in comp neuro @BrownU, interested in biophysical modeling, deep learning, and open-source software development

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Reposted by Nicholas Tolley
Ahmad Beyh @ahmadbeyh.bsky.social · 24/08/2026
We trained 3 RNN classes on a working memory task. (1) Vanilla RNNs were only task-optimized. (2) Masked RNNs had brain-like input/output constraints. (3) bioRNNs were further constrained such that their connections were shaped by the brain’s Euclidean geometry. (2/8)
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Thomas Serre @thomasserre.bsky.social · 13/08/2026
We're recruiting postdoc fellows in computational neuroscience for Brown's NIH T32 Training Program — brain & cognitive modeling from biophysics to AI, with connections to mental health & psychiatry. US citizens/PRs. Review begins Sept 1. @carneyinstitute @browncopsy apply.interfolio.com/190111
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Mehdi Senoussi @cogsenoussi.bsky.social · 31/07/2026
📢 PhD opening in comp. cog. neuro. in Toulouse: thalamo-frontal model of cognitive control. Modelling/EEG experience is welcome but not required. Application deadline: 8 Sept. 2026 Details: sdrive.cnrs.fr/s/eDrkeXfjdW... #CognitiveScience #Neuroscience #EEG #neuroskyence #compneurosky
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 16/06/2026
Spectral decompositions of neural voltage recordings are susceptible to model misspecifications that cause meaningful estimation error www.biorxiv.org/content/10.64898/20…
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Brad Postle @bradpostle.bsky.social · 12/06/2026
Postdoc position available at postlab.psych.wisc.edu. Pls send cv to postle@wisc.edu
postlab.psych.wisc.edu
PO-STL-AB
Our interests in human memory and cognition encompass the cognitive and neural basis of working memory, attention, control, and consciousness.News  Madison Symposium on Memory & Control. On 30 May 202...
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 09/06/2026
HSSM: A Widely Applicable Toolbox for Hierarchical Bayesian Neuro-cognitive Modeling www.biorxiv.org/content/10.64898/20…
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Prof Rick Adams @drrickadams.bsky.social · 18/05/2026
📢PhD job alert! A exciting PhD project that involves using MEG and biophysical modelling to try to predict effects of a glutamatergic treatment for psychosis... plus you can develop your own side project. Join our great team! www.ucl.ac.uk/work-at-ucl/...
ucl.ac.uk
UCL – University College London
UCL is consistently ranked as one of the top ten universities in the world (QS World University Rankings 2010-2022) and is No.2 in the UK for research power (Research Excellence Framework 2021).
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DurstewitzLab @durstewitzlab.bsky.social · 10/05/2026
In a #ICML2026 position paper we argue a dynamical systems perspective is needed to drive time series models forward: arxiv.org/abs/2602.16864 For TS, we need to move away from transformers that do not respect a system’s dynamical structure, esp. if out-of-domain generalization & insight is sought.
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Aperture Neuro @apertureohbm.bsky.social · 08/05/2026
Donoghue et al. introduce the Human Single-Neuron Pipeline, an open source processing pipeline for collecting and analyzing human single-neuron data: doi.org/10.52294/001... @ohbmossig.bsky.social @ohbmofficial.bsky.social #OpenDatasets #SpecialIssues
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Nicholas Tolley @ntolley.bsky.social · 05/05/2026
Super glad to have our team's work on clinical applications of neural simulations highlighted in this article! Trying to bring academic work to the real-world has been a great experience and I'm quite excited to continue these efforts with @dvwz.bsky.social and @jonescompneurolab.bsky.social
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 01/05/2026
Layer-specific wide-field calcium imaging of neocortical activity www.biorxiv.org/content/10.64898/20…
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Biological Psychiatry @biologicalpsych.bsky.social · 01/05/2026
In people at high risk for psychosis, reduced excitability of pyramidal cells predicts who will later convert to develop psychosis, suggesting this may be a root cause of schizophrenia rather than a consequence of the illness.
biologicalpsychiatryjournal.com
Biophysical modeling of excitation/inhibition balance and conversion to psychosis in the clinical high risk syndrome
Reduced mismatch negativity (MMN) and P300 event-related potential (ERP) components are widely replicated in schizophrenia and are also observed in individuals at clinical high risk for psychosis…
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Imaging Neuroscience @imagingneurosci.bsky.social · 01/05/2026
New paper in Imaging Neuroscience by Lindsey Power, Sylvain Baillet, et al: A neuroscientist’s guide to neural burst detection doi.org/10.1162/IMAG...
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Debbie Yee @debyee.bsky.social · 29/04/2026
Headed to #SOBP2026? Come visit our posters on stress and mental effort! F325: Investigating the Role of Serotonin in Stressor Controllability and Mental Effort Allocation (me!) S297: Learning and Generalization of Stressor Controllability for Mental Effort allocation (Tony El Nemer)
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Nicholas Tolley @ntolley.bsky.social · 27/04/2026
Really excited for this conference! We’ve all been digging deep into different ways to use EEG to better understand and treat psychiatric diseases If you’re at SOBP definitely stop by our posters if you want to chat biophysical mechanisms, biomarkers, and deep learning approaches to EEG analysis
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Jan R. Wessel @janw.bsky.social · 24/04/2026
New work, now out in PLoS Biology. Using intracranial recordings & EEG, we find that the human STN rapidly engages / releases motor inhibition depending on task context, does so in tight accord w/ frontal cortex, and shows little to no lateralization while doing so. journals.plos.org/plosbiology/...
journals.plos.org
A cortico-subthalamic circuit rapidly engages and releases inhibition of specific movements depending on the environmental context
How does the human brain stop movements under realistic conditions? Using intracranial recordings and multi-variate EEG decoding, this study shows that a fronto-basal ganglia circuit featuring the sub...
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Ann Huang @annhuang42.bsky.social · 23/04/2026
[ #ICLR2026 ] How do we know if two systems are performing the same computation when they are constantly driven by different external inputs? 🧠🤖 I’ll be presenting our novel method InputDSA tomorrow April 23 (2:15pm-4:45pm EDT in Pavilion 3 P3-#1614)📍 Come swing by our poster! I’d love to chat!
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 13/04/2026
Uncovering putative neural mechanisms of neurotherapeutic impacts on EEG using the Human Neocortical Neurosolver www.biorxiv.org/content/10.64898/20…
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
Special thanks to the team for helping put this together!✨✨ Stephanie Jones @jonescompneurolab.bsky.social , David Zhou @dvwz.bsky.social, Austin Soplata @asoplata.bsky.social, Katharina Duecker @katduecker.bsky.social, Carolina Fernandez Pujol, Joyce Gao, Dylan Daniels @dylansdaniels.bsky.social
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
This work represents a new research direction the team is taking. If you study EEG biomarkers of neurotherapeutics we'd love to start a conversation!
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
Insights gained from biophysical modeling with the @hnnsolver.bsky.social software can help at many decision points in the neurotherapeutic development pipeline, including building evidence of target engagement, and for target selection and dosing
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
In this new preprint from the @hnnsolver.bsky.social team, we lay out a protocol for how biophysical modeling can link treatment-induced changes in EEG to cell- and circuit-level mechanisms of action
The default HNN model is used as a starting point to test hypotheses by either manually altering the values of the chosen model parameters, or using automated optimization and inference algorithms. Differences in parameter values pre-to post-treatment correspond to model-based predictions.
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
Measuring pre- to post/treatment EEG biomarkers has the potential to help with this goal, but current methods fail to link these biomarkers to concrete mechanisms of actions that causally alter the EEG. This missing link hinders the utility of EEG in advancing effective neurotherapeutics
Biophysical modeling allows for testing mechanistic hypotheses that explain how EEG biomarkers emerge and change with drugs. Hypotheses about which drug mechanisms lead to distinct brain activity patterns must be constructed, and corresponding model parameters identified.
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
One of the major challenges in neurotherapeutic development is understanding how treatments are impacting individual brain networks
Modeling EEG biomarkers begins with picking a specific brain signal that is reliably different between patient populations. An example of a hypothetical EEG biomarker is an auditory event related potential (ERP) that is suppressed in post-treatment (red) relative to pre-treatment (blue).
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Nicholas Tolley @ntolley.bsky.social · 17/04/2026
Happy to share a new preprint from the @hnnsolver.bsky.social team!🧠💻🎉 "Uncovering putative neural mechanisms of neurotherapeutic impacts on EEG using the Human Neocortical Neurosolver" 📝 www.biorxiv.org/content/10.6...
Biophysical modeling to develop and test mechanistic hypotheses underlying pharmacological EEG biomarkers.

Top: Modeling EEG biomarkers begins with picking a specific brain signal that is reliably different between patient populations. An example of a hypothetical EEG biomarker is an auditory event related potential (ERP) that is suppressed in post-treatment (red) relative to pre-treatment (blue). Middle: Biophysical modeling allows for testing mechanistic hypotheses that explain how EEG biomarkers emerge and change with drugs. Hypotheses about which drug mechanisms lead to distinct brain activity patterns must be constructed, and corresponding model parameters identified. Bottom: The default HNN model is used as a starting point to test hypotheses by either manually altering the values of the chosen model parameters, or using automated optimization and inference algorithms. Differences in parameter values pre-to post-treatment correspond to model-based predictions.
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Athena Akrami @athenaakrami.bsky.social · 13/04/2026
New preprint! 🧠 How do RNNs learn abstract rules from sequences, independent of specific stimuli? By Vezha Boboeva, with Alberto Pezzotta & George Dimitriadis "From sequences to schemas: low-rank recurrent dynamics underlie abstract relational representations" www.biorxiv.org/content/10.6...
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CMC Unit @cmc-unit.bsky.social · 07/04/2026
Thrilled to see the second paper of the lab out 🤩 Check it out if you need a method to infer causality from neural data, even when the signal is short! Paper: joss.theoj.org/papers/10.21... Code: github.com/CMC-lab/Tran...
joss.theoj.org
TranCIT: Transient Causal Interaction Toolbox
Nouri et al., (2025). TranCIT: Transient Causal Interaction Toolbox. Journal of Open Source Software, 10(116), 9302, https://doi.org/10.21105/joss.09302
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Rudebeck Lab @rudebecklab.bsky.social · 04/04/2026
Want a dataset to test ideas on neural basis of decision making or how areas interact as we make choices? Check out our data published today @rudebecklab.bsky.social. >16,000 single neurons from 22 anatomically confirmed areas in macaques performing a decision task. www.nature.com/articles/s41...
nature.com
Dataset of cortical and subcortical single neuron activity during value-based tasks in macaque monkey - Scientific Data
Scientific Data - Dataset of cortical and subcortical single neuron activity during value-based tasks in macaque monkey
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James McAllister @jajmca.bsky.social · 02/04/2026
Really excited to share a new preprint! 𝗛𝗼𝘄 𝗱𝗼 𝗯𝗿𝗮𝗶𝗻𝘀 𝘀𝘁𝗮𝘆 𝗿𝗼𝗯𝘂𝘀𝘁 & 𝗲𝗳𝗳𝗶𝗰𝗶𝗲𝗻𝘁 𝘄𝗵𝗶𝗹𝗲 𝗯𝗲𝗶𝗻𝗴 𝗶𝗻𝗰𝗿𝗲𝗱𝗶𝗯𝗹𝘆 𝘀𝗽𝗮𝗿𝘀𝗲? We explore how! www.biorxiv.org/content/10.6... We built Connectome-based Neural Networks (CoNNs) using Drosophila wiring (larva&adult) & compared with random networks with same sparsity.
Constructing connectome-based neural networks
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Konrad Kording @kordinglab.bsky.social · 31/03/2026
Preprint out arguing that we should build the techology to translate (compile) molecularly annotated connectomes into dynamics. I think this is incredibly important. arxiv.org/abs/2603.25713
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Todd Morrill @toddmorrill.bsky.social · 17/03/2026
This work started when Christian Pehle, @tonyzador.bsky.social, and I found that training sequentially (consuming/producing one spike at a time) in JAX was prohibitively slow. You certainly can consume multiple spikes in parallel—TLDR; just use an associative scan—but... 2/N
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John Tuthill @tuthill.bsky.social · 24/03/2026
🧵 New preprint led by @bingbrunton.bsky.social, @elliottabe.bsky.social, @lawrencehu.bsky.social We gave a worm brain control of a fly body and it walked What did we learn? Nothing, other than deep reinforcement learning is effective We call it the digital sphinx www.biorxiv.org/content/10.6...
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Nastya Krouglova @anastasiakrouglova.bsky.social · 22/03/2026
Our paper “Multifidelity Simulation-based Inference for Computationally Expensive Simulators” has been accepted at ICLR 2026! 🥳 We hope this can be a practical solution for anyone analysing and doing inference on computationally expensive simulators. Paper: openreview.net/pdf?id=bj0dc...
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Joel I Berger @joelberger.bsky.social · 21/03/2026
We have a new preprint examining single neuron responses in humans undergoing TMS (www.biorxiv.org/content/10.6...). The excellent Charlie Dickey led the way, and I had the privilege to co-supervise this work with @coreykeller.bsky.social and @aaronboes.bsky.social 🧵 (1/7) 🧠🟦 🧠💻
Image showing the paradigm for recording single neurons in a variety of brain regions in humans, while single-pulse TMS was applied to dlPFC. One subpanel shows that single neurons were able to be resolved very early (8ms) after the single-pulse stimulation. Another subpanel shows two example neuron waveforms, along with their inter-spike interval distributions. The final subpanels show spike density functions overlaid on raster plots for the same neuron, separately for active and sham stimulation, in order to demonstrate that active (but not sham) stimulation increased activity in this example neuron.
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 21/03/2026
A Spatially Structured Spiking Network Model of Beta Traveling Waves and Their Attenuation in Motor Cortex www.biorxiv.org/content/10.64898/20…
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Andrew Lampinen @lampinen.bsky.social · 17/03/2026
Pleased to share that our paper "Representation Biases: Variance is Not Always a Good Proxy for Importance" is now out as Theory/New Concepts paper in eNeuro! www.eneuro.org/content/13/3... 1/
eneuro.org
Representation Biases: Variance Is Not Always a Good Proxy for Importance
A central approach in neuroscience is to analyze neural representations as a means to understand a system's function, through the use of methods like principal component analysis, regression, and repr...
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
In the future we hope to apply this framework to biophysical models of EEG generation like @hnnsolver.bsky.social providing a link between biomarkers and behaviorally relevant neural dynamics Special thanks to my amazing advisor Stephanie Jones @jonescompneurolab.bsky.social for all your support!
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
We also went deeper into what aspects of the NMDA receptor promote the emergence of attractor dynamics and found that the unique combination of slow receptor time constants and a magnesium block are both critical for task performance
Figure showing neural trajectories to modified versions of the NMDA receptor arriving at the dendrite where either 1) the receptor just exhibits slow time constants, or 2) the receptor just exhibits a magnesium block. Neither variant was successfully trained to solve the task, suggesting that the unique properties of NMDA receptors are necessary for the emergence of fixed point attractors.
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
In line with previous literature, slow time constant synapses (i.e. NMDA receptors) were shown to be extremely important for the emergence of attractor dynamics What’s surprising is that this result holds even when the network’s connectivity and active ion channels are freely changed
Figure of loss curves during training for different network variants where extrinsic inputs were fixed. Limiting extrinsic inputs to signal through NMDA receptors produced the best trained networks. AMPA inputs at the dendrite failed to solve the task.
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
We do this by selectively constraining certain biophysical properties, and allowing all others to be freely optimized
Schematic figure illustrating how different biophysical properties are evaluated for their importance to generate fixed point attractors, 1) fix extrinsic inputs (i.e. NMDA or AMPA inputs to the dendrite or soma), 2) train cell and network parameter (i.e. all other parameters of the model are freely modified), 3) evaluate task performance (the emergence of distinct fixed point attractors for each input is considered a successfully trained network)
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
Using the new modeling framework Jaxley, we attempt to characterize how fixed point attractors emerge in RNNs composed of biophysically detailed neurons
Visualization of the different scales of the biophysical model used in the paper. 1) Subcellular where voltage traces of a dendritic action potential are shown alongside the morphology of a multicompartment neuron, 2) cell-level where a spike raster shows how a single neuron exhibits preferential spiking to different inputs to the network, 3) network-level where a spike raster and neural trajectory plot both show that the network produces sustained changes in activity to inputs.
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
Currently there’s a lot of work understanding attractor dynamics in RNNs, as they are readily linked to cognitive tasks and behaviors Since RNNs typically contain simplified neurons, it is unclear how biophysical properties of realistic neurons impact the emergence of attractor dynamics
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Nicholas Tolley @ntolley.bsky.social · 18/03/2026
Happy to share a new preprint from my PhD thesis! “A novel framework for expanding RNNs with biophysical detail to solve cognitive tasks” 🧠💻 📝 www.biorxiv.org/content/10.6... @jonescompneurolab.bsky.social
Multipanel figure illustrating the key components of the paper: 1) biophysical reservoir computing where a network of biophysically detailed excitatory and inhibitory neurons are randomly connected, receive a brief input, and produce a sustained spiking pattern in response, 2) an illustration of the task the biophysical reservoir computer is trained on: a simplified working memory task where the network must produce distinct fixed point attractors in response to different inputs.
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bioRxiv Neuroscience @biorxiv-neursci.bsky.social · 17/03/2026
Deep-learning-assisted simulation of a cortical circuit: integrating anatomy, physiology and function www.biorxiv.org/content/10.64898/20…
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Decision, Action, and Neural Computation (DANC) lab @danclab.bsky.social · 09/03/2026
We've been saying for a while now that beta bursts might be functionally heterogeneous. Check out @quentinmoreau.bsky.social's paper where we show that different types of bursts have different relationships to behavior in a sensorimotor adaptation task 👇👇👇
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DANDI Archive @dandiarchive.org · 27/02/2026
Mission: record hippocampal place cells in zero gravity Crew: 3 rats with electrode arrays Vehicle: Space Shuttle Columbia Status: data now publicly available on DANDI, 28 years later The ratstronauts' mission is finally complete. 🐀🚀 h/t NASA about.dandiarchive.org/blog/2026/02...
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Natalie Schaworonkow @nschawor.bsky.social · 20/02/2026
underappreciated concept 🙂 for more dipoles: neighboring dipoles have different orientations & can have different stimulus preferences. so even though topographies look similar, subtle differences remain. maybe that's why it is possible to decode information from relatively few sensors?
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Alina Studenova @studenova.bsky.social · 20/02/2026
The angle of the dipole obviously matters. If active dipoles in two conditions are slightly misaligned, a difference can be observed. However, this difference is not driven by differences in amplitudes, but only by differences in orientations. Here, I simulated such a scenario. #brainmovies
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Tian Wang @tianw0318.bsky.social · 05/02/2026
Excited to share our new findings: distinct neural dynamics in prefrontal and premotor cortex during flexible decision making, preprinted on biorxiv. www.biorxiv.org/content/10.6...
biorxiv.org
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