117 results match your criteria: "Churchill College[Affiliation]"

Insulation between adjacent TADs is controlled by the width of their boundaries through distinct mechanisms.

Proc Natl Acad Sci U S A

March 2025

Department of Biology, Computational Biology and Applied Mathematics, Ecole Normale Supérieure, Institute of Biology at Ecole normale Superieure, Université Paris Sciences et Lettres, Paris 75005, France.

Topologically associating domains (TADs) are sub-Megabase regions in vertebrate genomes with enriched intradomain interactions that restrict enhancer-promoter contacts across their boundaries. However, the mechanisms that separate TADs remain incompletely understood. Most boundaries between TADs contain CTCF binding sites (CBSs), which individually contribute to the blocking of Cohesin-mediated loop extrusion.

View Article and Find Full Text PDF

Mapping cellular organization in the developing brain presents significant challenges due to the multidimensional nature of the data, characterized by complex spatial patterns that are difficult to interpret without high-throughput tools. Here, we present DeepCellMap, a deep-learning-assisted tool that integrates multi-scale image processing with advanced spatial and clustering statistics. This pipeline is designed to map microglial organization during normal and pathological brain development and has the potential to be adapted to any cell type.

View Article and Find Full Text PDF

Research has shown that patients with post-stroke aphasia may encounter difficulties in producing inflectional morphemes. Interestingly, they also show distinct challenges with the inflectional morphemes of homophones, such as the plural marker and the possessive marker in English. However, previous studies have predominantly focused on morphemes in European languages.

View Article and Find Full Text PDF

Embedded Ethics in Practice: A Toolbox for Integrating the Analysis of Ethical and Social Issues into Healthcare AI Research.

Sci Eng Ethics

December 2024

Institute of History and Ethics in Medicine, Department of Preclinical Medicine, TUM School of Medicine and Health, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.

Integrating artificial intelligence (AI) into critical domains such as healthcare holds immense promise. Nevertheless, significant challenges must be addressed to avoid harm, promote the well-being of individuals and societies, and ensure ethically sound and socially just technology development. Innovative approaches like Embedded Ethics, which refers to integrating ethics and social science into technology development based on interdisciplinary collaboration, are emerging to address issues of bias, transparency, misrepresentation, and more.

View Article and Find Full Text PDF

Voltage mapping in subcellular nanodomains using electro-diffusion modeling.

J Chem Phys

July 2024

Group of Data Modeling, Computational Biology and Applied Mathematics, École Normale Supérieure - Université PSL, 75005 Paris, France.

Voltage distribution in sub-cellular micro-domains such as neuronal synapses, small protrusions, or dendritic spines regulates the opening and closing of ionic channels, energy production, and thus, cellular homeostasis and excitability. Yet how voltage changes at such a small scale in vivo remains challenging due to the experimental diffraction limit, large signal fluctuations, and the still limited resolution of fast voltage indicators. Here, we study the voltage distribution in nano-compartments using a computational approach based on the Poisson-Nernst-Planck equations for the electro-diffusion motion of ions, where inward and outward fluxes are generated between channels.

View Article and Find Full Text PDF

Neurotransmitter release relies on the regulated fusion of synaptic vesicles (SVs) that are tightly packed within the presynaptic bouton of neurons. The mechanism by which SVs are clustered at the presynapse, while preserving their ability to dynamically recycle to support neuronal communication, remains unknown. Synapsin 2a (Syn2a) tetramerization has been suggested as a potential clustering mechanism.

View Article and Find Full Text PDF

Analyzing Photoactivation with Diffusion Models to Study Transport in the Endoplasmic Reticulum Network.

Methods Mol Biol

February 2024

Applied Mathematics and Computational Biology, Ecole Normale Supérieure, Paris, France.

Photoactivation is a paradigm consisting in local molecular fluorescent activation by laser illumination in a chosen region (source) while measuring the concentration at a target region. Data-driven modeling is concerned with the following questions: how from the measurement in these two regions is it possible to infer the properties of molecular propagation? How is it possible to use such responses to infer motions occurring in networks such as the endoplasmic reticulum? In this book chapter, we shall review the data-driven analysis based on diffusion-transport models and numerical simulations to interpret the photoactivation dynamics and extract biophysical parameters. We will discuss modeling approaches to reconstruct local network properties from photoactivation transients.

View Article and Find Full Text PDF

Chromatin phase separated nanoregions explored by polymer cross-linker models and reconstructed from single particle trajectories.

PLoS Comput Biol

January 2024

Group of Computational Biology and Applied Mathemathics, Ecole Normale Supérieure, IBENS, Université PSL, Paris, France.

Phase separated domains (PSDs) are ubiquitous in cell biology, representing nanoregions of high molecular concentration. PSDs appear at diverse cellular domains, such as neuronal synapses but also in eukaryotic cell nucleus, limiting the access of transcription factors and thus preventing gene expression. We develop a generalized cross-linker polymer model, to study PSDs: we show that increasing the number of cross-linkers induces a polymer condensation, preventing access of diffusing molecules.

View Article and Find Full Text PDF

Mapping general anesthesia states based on electro-encephalogram transition phases.

Neuroimage

January 2024

Group of Data Modeling and Computational Biology, Institut de Biologie (IBENS), École Normale Supérieure CNRS, Université PSL Paris, France; DAMPT, University of Cambridge and Churchill College, CB30DS, Cambridge, UK. Electronic address:

Cortical electro-encephalography (EEG) served as the clinical reference for monitoring unconsciousness during general anesthesia. The existing EEG-based monitors classified general anesthesia states as underdosed, adequate, or overdosed, lacking predictive power due to the absence of transition phases among these states. In response to this limitation, we undertook an analysis of the EEG signal during isoflurane-induced general anesthesia in mice.

View Article and Find Full Text PDF
Article Synopsis
  • Yemen has been facing the largest cholera outbreak in modern history since 2016, with a significant rise in multidrug-resistant (MDR) cholera strains observed since 2018.
  • Analysis of 260 V. cholerae isolates from 2018 to 2019 revealed that a majority (84%) were part of the O1 serogroup and belonged to the seventh pandemic El Tor lineage, while the remaining 16% were non-toxigenic strains from different lineages.
  • The emergence of MDR plasmids in cholera strains indicates a potential genetic exchange between epidemic and endemic strains, underscoring the need for ongoing genomic surveillance to manage and control cholera effectively.
View Article and Find Full Text PDF

Topologically Associating Domains (TADs) separate vertebrate genomes into insulated regulatory neighborhoods that focus genome-associated processes. TADs are formed by Cohesin-mediated loop extrusion, with many TAD boundaries consisting of clustered binding sites of the CTCF insulator protein. Here we determine how this clustering of CTCF binding contributes to the blocking of loop extrusion and the insulation between TADs.

View Article and Find Full Text PDF

Spinteract: a program to refine magnetic interactions to diffuse scattering data.

J Phys Condens Matter

September 2023

Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America.

Magnetic diffuse scattering-the broad magnetic scattering features observed in neutron-diffraction data above a material's magnetic ordering temperature-provides a rich source of information about the material's magnetic Hamiltonian. However, this information has often remained under-utilised due to a lack of available computer software that can fit values of magnetic interaction parameters to such data. Here, an open-source computer program, Spinteract, is presented, which enables straightforward refinement of magnetic interaction parameters to powder and single-crystal magnetic diffuse scattering data.

View Article and Find Full Text PDF

Diversity of dynamic voltage patterns in neuronal dendrites revealed by nanopipette electrophysiology.

Nanoscale

July 2023

Centre for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Labex Memolife, Paris, France.

Dendrites and dendritic spines are the essential cellular compartments in neuronal communication, conveying information through transient voltage signals. Our understanding of these compartmentalized voltage dynamics in fine, distal neuronal dendrites remains poor due to the difficulties inherent to accessing and stably recording from such small, nanoscale cellular compartments for a sustained time. To overcome these challenges, we use nanopipettes that permit long and stable recordings directly from fine neuronal dendrites.

View Article and Find Full Text PDF

During the COVID-19 pandemic, national triage guidelines were developed to address the anticipated shortage of life-saving resources, should ICU capacities be overloaded. Rationing and triage imply that in addition to individual patient interests, interests of population health have to be integrated. The transfer of theoretical and empirical knowledge into feasible and useful practice models and their implementation in clinical settings need to be improved.

View Article and Find Full Text PDF

O37: one of the exceptions that prove the rule.

Microb Genom

April 2023

Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK.

Between 1965 and 1968, outbreaks of cholera in Sudan and former Czechoslovakia provoked considerable public health concern. These still represent important historical events that need to be linked to the growing genomic evidence describing the aetiological agent of cholera, . Whilst O1 serogroup are canonically associated with epidemic and pandemic cholera, these events were caused by a clone of toxigenic O37 that may be more globally distributed than just to Europe and North Africa.

View Article and Find Full Text PDF

Spectral EEG correlations from the different phases of general anesthesia.

Front Med (Lausanne)

March 2023

Group of Data Modeling, Computational Biology and Predictive Medicine, Institut de Biologie (IBENS), École Normale Supérieure, Université PSL, Paris, France.

Introduction: Electroencephalography (EEG) signals contain transient oscillation patterns commonly used to classify brain states in responses to action, sleep, coma or anesthesia.

Methods: Using a time-frequency analysis of the EEG, we search for possible causal correlations between the successive phases of general anesthesia. We hypothesize that it could be possible to anticipate recovery patterns from the induction or maintenance phases.

View Article and Find Full Text PDF

At presynaptic active zones (AZs), conserved scaffold protein architectures control synaptic vesicle (SV) release by defining the nanoscale distribution and density of voltage-gated Ca channels (VGCCs). While AZs can potentiate SV release in the minutes range, we lack an understanding of how AZ scaffold components and VGCCs engage into potentiation. We here establish dynamic, intravital single-molecule imaging of endogenously tagged proteins at AZs undergoing presynaptic homeostatic potentiation.

View Article and Find Full Text PDF

How large the number of redundant copies should be to make a rare event probable.

Phys Rev E

December 2022

Group of Data Modeling, Computational Biology and Applied Mathematics, Ecole Normale Supérieure-PSL, 75005 Paris, France.

The redundancy principle provides a framework to study how rare events are made possible with probability 1 in accelerated time, by making many copies of similar random searchers. However, what is a large n? To estimate large n with respect to the geometrical properties of a domain and the dynamics, we present here a criterion based on splitting probabilities between a small fraction of the exploration space associated with an activation process and other absorbing regions where trajectories can be terminated. We obtain explicit computations especially when there is a killing region located inside the domain that we compare with stochastic simulations.

View Article and Find Full Text PDF

High-throughput super-resolution single-particle trajectory analysis reconstructs organelle dynamics and membrane reorganization.

Cell Rep Methods

August 2022

Group of Data Modeling and Computational Biology, IBENS, Ecole Normale Supérieure, 75005 Paris, France.

Super-resolution imaging can generate thousands of single-particle trajectories. These data can potentially reconstruct subcellular organization and dynamics, as well as measure disease-linked changes. However, computational methods that can derive quantitative information from such massive datasets are currently lacking.

View Article and Find Full Text PDF

DNA supercoiling and nucleoid-associated proteins (NAPs) are two of the factors that govern the architecture of the bacterial genome, influencing the expression of the genetic information that it contains. Alterations to DNA topology, and to the numbers and types of NAPs, have pleiotropic effects on gene expression, suggesting that modifications to the production patterns of DNA topoisomerases and/or NAPs are likely to result in marked impacts on bacterial physiology. Knockout mutations in the genes encoding these proteins (where the mutants remain viable) result in clear physiological effects.

View Article and Find Full Text PDF

Systemising triage: COVID-19 guidelines and their underlying theories of distributive justice.

Med Health Care Philos

December 2022

Churchill College, University of Cambridge, Storey's Way, Cambridge, CB3 0DS, UK.

The COVID-19 pandemic has been overwhelming public health-care systems around the world. With demand exceeding the availability of medical resources in several regions, hospitals have been forced to invoke triage. To ensure that this difficult task proceeds in a fair and organised manner, governments scrambled experts to draft triage guidelines under enormous time pressure.

View Article and Find Full Text PDF

In the dense metal-organic framework Na[Mn(HCOO)_{3}], Mn^{2+} ions (S=5/2) occupy the nodes of a "trillium" net. We show that the system is strongly magnetically frustrated: the Néel transition is suppressed well below the characteristic magnetic interaction strength; short-range magnetic order persists far above the Néel temperature; and the magnetic susceptibility exhibits a pseudo-plateau at 1/3-saturation magnetization. A simple model of nearest-neighbor Heisenberg antiferromagnetic and dipolar interactions accounts quantitatively for all observations, including an unusual 2-k magnetic ground state.

View Article and Find Full Text PDF

Harold Wilson's attack on 'Selsdon Man' in the run-up to the 1970 general election has generally been seen as a flawed rhetorical gambit, which inadvertently gave coherence to Edward Heath's policies. The subsequent invocation of 'Selsdon' by critics of Heath's 'u-turns' has meant that the episode has mainly attracted scrutiny from historians of the Conservative Party. Yet the debate over Selsdon can also be seen as a landmark in Wilson's transition from the 'modernizing' politics of the 1960s to a more defensive posture, in which he presented Labour as a bulwark against regressive market-liberal policies.

View Article and Find Full Text PDF

Emergence and fragmentation of the alpha-band driven by neuronal network dynamics.

PLoS Comput Biol

December 2021

Group of Applied Mathematics and Computational Biology, IBENS, Ecole Normale Supérieure, PSL University, Paris, France.

Rhythmic neuronal network activity underlies brain oscillations. To investigate how connected neuronal networks contribute to the emergence of the α-band and to the regulation of Up and Down states, we study a model based on synaptic short-term depression-facilitation with afterhyperpolarization (AHP). We found that the α-band is generated by the network behavior near the attractor of the Up-state.

View Article and Find Full Text PDF

Introduction: Visible spaces of sex work are controversial and contested spaces. This paper explores the relationship between the legal framing of sex work and local policy and how this impacts upon the health and safety of sex workers who use those spaces.

Methods: This paper is based on data collected from a Winston Churchill Memorial Trust Travel Fellowship in 2016.

View Article and Find Full Text PDF