1,062 results on '"Cossart P"'
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2. Constancy of the Hilbert-Samuel function
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Cossart, Vincent, Piltant, Olivier, and Schober, Bernd
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Mathematics - Algebraic Geometry - Abstract
The Hilbert-Samuel function and the multiplicity function are fundamental locally defined invariants on Noetherian schemes. They have been playing an important role in desingularization for many years. Bennett studied upper semicontinuity of the Hilbert-Samuel function on schemes and proved that it is non increasing under permissible blowing ups. The latter are blowing ups at regular subschemes along which the singular scheme is normally flat. For a reduced scheme, the Hilbert-Samuel function is constant if and only if it is regular: this translates the question of resolution of singularities into a problem of lowering the Hilbert-Samuel function. We show here that this result can be extended to non reduced schemes as follows: Given a locally Noetherian scheme X such that the local rings are excellent for every point, then the Hilbert-Samuel function is constant on X if and only if X is normally flat along its reduction and the reduction itself is regular.
- Published
- 2023
3. Tapered multi-core fiber for lensless endoscopes
- Author
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Moussawi, Fatima El, Hofer, Matthias, Labat, Damien, Cassez, Andy, Bouwmans, Géraud, Sivankutty, Siddharth, Cossart, Rosa, Vanvincq, Olivier, Rigneault, Hervé, and Andresen, Esben Ravn
- Subjects
Physics - Optics - Abstract
We present a novel fiber-optic component, a "tapered multi-core fiber (MCF)", designed for integration into ultra-miniaturized endoscopes for minimally invasive two-photon point-scanning imaging and to address the power delivery issue that has faced MCF based lensless endoscopes. With it we achieve experimentally a factor 6.0 increase in two-photon signal yield while keeping the ability to point-scan by the memory effect, and a factor 8.9 sacrificing the memory effect. To reach this optimal design we first develop and validate a fast numerical model capable of predicting the essential properties of an arbitrarily tapered MCF from its structural parameters. We then use this model to identify the tapered MCF design parameters that result in a chosen set of target properties (point-spread function, delivered power, presence or absence of memory effect). We fabricate the identified target designs by stack-and-draw and post-processing on a CO$_{2}$ laser-based glass processing and splicing system. Finally we demonstrate the performance gain of the fabricated tapered MCFs in two-photon imaging when used in a lensless endoscope system. Our results show that tailoring of the taper profile brings new degrees of freedom that can be efficiently exploited for lensless endoscopes.
- Published
- 2022
4. Prominent in vivo influence of single interneurons in the developing barrel cortex
- Author
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Bollmann, Yannick, Modol, Laura, Tressard, Thomas, Vorobyev, Artem, Dard, Robin, Brustlein, Sophie, Sims, Ruth, Bendifallah, Imane, Leprince, Erwan, de Sars, Vincent, Ronzitti, Emiliano, Baude, Agnès, Adesnik, Hillel, Picardo, Michel Aimé, Platel, Jean-Claude, Emiliani, Valentina, Angulo-Garcia, David, and Cossart, Rosa
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- 2023
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5. Modelling and Simulation of Power Systems with Grid-Connected Converters in OpenModelica
- Author
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Llerins, Lluc Figueras, Lacerda, Vinícius Albernaz, Guironnet, Adrien, Cossart, Quentin, Prieto-Araujo, Eduardo, and Gomis-Bellmunt, Oriol
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Electrical Engineering and Systems Science - Systems and Control - Abstract
This paper analyses the capabilities of the OpenModelica environment to perform electromagnetic transient (EMT) type simulations of power transmission systems with grid-connected converters. A power transmission system has been modelled and simulated in OpenModelica and Simulink to compare both tools in terms of accuracy, robustness, flexibility and computational performance. Power system transient studies such as faults and switching of capacitor banks have been performed. The results confirmed an excellent overall agreement between both software and demonstrated a remarkable potential for using OpenModelica for EMT-type modelling and simulation of future power electronic dominated grids.
- Published
- 2021
6. Protocol to image and analyze hippocampal network dynamics in non-anesthetized mouse pups
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Mirindra R. Ratsifandrihamanana, Robin F. Dard, Julien Denis, Rosa Cossart, and Michel A. Picardo
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Microscopy ,Neuroscience ,Science (General) ,Q1-390 - Abstract
Summary: Two-photon calcium imaging is a powerful technique that has revolutionized our understanding of how neural circuit dynamics supports different behaviors and cognitive processes. However, performing imaging during development remains challenging. Here, we provide a protocol to image CA1 neurons in mouse pups as well as a pipeline of analysis to analyze and share the data. We describe steps for intracerebroventricular injection, cranial window surgery, two-photon calcium imaging, and analysis of imaging data.For complete details on the use and execution of this protocol, please refer to Dard et al.1 and Denis et al.2 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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- 2023
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7. Exploring Transplant Medication-Taking Behaviours in Older Adult Kidney Transplant Recipients: A Qualitative Study of Semi-Structured Interviews
- Author
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Cossart, Amelia R., Staatz, Christine E., Isbel, Nicole M., Campbell, Scott B., and Cottrell, W. Neil
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- 2022
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8. A bacterial virulence factor interacts with the splicing factor RBM5 and stimulates formation of nuclear RBM5 granules
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Renaud Pourpre, Goran Lakisic, Emma Desgranges, Pascale Cossart, Alessandro Pagliuso, and Hélène Bierne
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Medicine ,Science - Abstract
Abstract L. monocytogenes causes listeriosis, a foodborne disease that is particularly dangerous for immunocompromised individuals and fetuses. Several virulence factors of this bacterial pathogen belong to a family of leucine-rich repeat (LRR)-containing proteins called internalins. Among these, InlP is known for its role in placental infection. We report here a function of InlP in mammalian cell nucleus organization. We demonstrate that bacteria do not produce InlP under in vitro culture conditions. When ectopically expressed in human cells, InlP translocates into the nucleus and changes the morphology of nuclear speckles, which are membrane-less organelles storing splicing factors. Using yeast two-hybrid screen, immunoprecipitation and pull-down experiments, we identify the tumor suppressor and splicing factor RBM5 as a major nuclear target of InlP. InlP inhibits RBM5-induced cell death and stimulate the formation of RBM5-induced nuclear granules, where the SC35 speckle protein redistributes. Taken together, these results suggest that InlP acts as a nucleomodulin controlling compartmentalization and function of RBM5 in the nucleus and that L. monocytogenes has developed a mechanism to target the host cell splicing machinery.
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- 2022
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9. Editorial
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Cossart, Pascale and Schwartz, Maxime
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Biology (General) ,QH301-705.5 - Published
- 2022
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10. Step by step: cells with multiple functions in cortical circuit assembly
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Cossart, Rosa and Garel, Sonia
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- 2022
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11. Invariance of Hironaka's characteristic polyhedron
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Cossart, Vincent, Jannsen, Uwe, and Schober, Bernd
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Mathematics - Algebraic Geometry ,Mathematics - Commutative Algebra - Abstract
We show that given a face of Hironaka's characteristic polyhedron, it does only depend on the singularity and a flag defined by the linear form determining the face. As a consequence we get that certain numerical data obtained from the characteristic polyhedron are invariants of the singularity. In particular, they do not depend on an embedding., Comment: 29 pages, 5 figures
- Published
- 2018
12. Cortical neuronal assemblies coordinate with EEG microstate dynamics during resting wakefulness
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Richard Boyce, Robin F. Dard, and Rosa Cossart
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CP: Neuroscience ,Biology (General) ,QH301-705.5 - Abstract
Summary: The disruption of cortical assembly activity has been associated with anesthesia-induced loss of consciousness. However, the relationship between cortical assembly activity and the variations in consciousness associated with natural vigilance states remains unclear. Here, we address this by performing vigilance state-specific clustering analysis on 2-photon calcium imaging data from the sensorimotor cortex in combination with global electroencephalogram (EEG) microstate analysis derived from multi-EEG signals obtained over widespread cortical locations. We report no difference in the structure of assembly activity during quiet wakefulness (QW), non-rapid eye movement sleep (NREMs), or REMs, despite the latter two vigilance states being associated with significantly reduced levels of consciousness relative to QW. However, we describe a significant coordination between global EEG microstate dynamics and general local cortical assembly activity during periods of QW, but not sleep. These results suggest that the coordination of cortical assembly activity with global brain dynamics could be a key factor of sustained conscious experience.
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- 2023
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13. A bacterial virulence factor interacts with the splicing factor RBM5 and stimulates formation of nuclear RBM5 granules
- Author
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Pourpre, Renaud, Lakisic, Goran, Desgranges, Emma, Cossart, Pascale, Pagliuso, Alessandro, and Bierne, Hélène
- Published
- 2022
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14. Pasteur's legacy persists: an interview with Pascale Cossart
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Pascale Cossart
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Medicine ,Pathology ,RB1-214 - Published
- 2022
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15. Reconstructing 50,000 years of human history from our DNA: lessons from modern genomics
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Rotival, Maxime, Cossart, Pascale, and Quintana-Murci, Lluis
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Human history ,Population genetics ,Anthropology ,Genomics ,Ancient DNA ,Domesticated species ,Biology (General) ,QH301-705.5 - Abstract
The advent of high throughput sequencing approaches and ancient DNA techniques have enabled reconstructing the history of human populations at an unprecedented level of resolution. The symposium from the French Academy of Sciences “50,000 ans d’épopée humaine dans notre ADN” has reviewed some of the latest contributions from the fields of genomics, archaeology, and linguistics to our understanding of $>$300,000 years of human history. DNA has revealed the richness of the human journey, from the deep divergences between human populations in Africa, to the first encounters of Homo Sapiens with other hominins on their way to Eurasia and the peopling of Remote Oceania. The symposium has also emphasized how migrations, cultural practices, and environmental pathogens have contributed to shape the genetic diversity of modern humans, through admixture, genetic drift or genetic adaptation. Finally, special attention was also given to how human behaviours have shaped the genome of other species, through the spreading of microbes and pathogens, as in the case of Yersinia Pestis, or through domestication, as elegantly demonstrated for dogs, horses, and apples. Altogether, this conference illustrated how the complex history of human populations is tightly linked with their contemporary genetic diversity that, in turn, has direct effects on their identity and health.
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- 2021
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16. The rapid developmental rise of somatic inhibition disengages hippocampal dynamics from self-motion
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Robin F Dard, Erwan Leprince, Julien Denis, Shrisha Rao Balappa, Dmitrii Suchkov, Richard Boyce, Catherine Lopez, Marie Giorgi-Kurz, Tom Szwagier, Théo Dumont, Hervé Rouault, Marat Minlebaev, Agnès Baude, Rosa Cossart, and Michel A Picardo
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hippocampus ,development ,two-photon calcium imaging ,inhibition ,network dynamics ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Early electrophysiological brain oscillations recorded in preterm babies and newborn rodents are initially mostly driven by bottom-up sensorimotor activity and only later can detach from external inputs. This is a hallmark of most developing brain areas, including the hippocampus, which, in the adult brain, functions in integrating external inputs onto internal dynamics. Such developmental disengagement from external inputs is likely a fundamental step for the proper development of cognitive internal models. Despite its importance, the developmental timeline and circuit basis for this disengagement remain unknown. To address this issue, we have investigated the daily evolution of CA1 dynamics and underlying circuits during the first two postnatal weeks of mouse development using two-photon calcium imaging in non-anesthetized pups. We show that the first postnatal week ends with an abrupt shift in the representation of self-motion in CA1. Indeed, most CA1 pyramidal cells switch from activated to inhibited by self-generated movements at the end of the first postnatal week, whereas the majority of GABAergic neurons remain positively modulated throughout this period. This rapid switch occurs within 2 days and follows the rapid anatomical and functional surge of local somatic GABAergic innervation. The observed change in dynamics is consistent with a two-population model undergoing a strengthening of inhibition. We propose that this abrupt developmental transition inaugurates the emergence of internal hippocampal dynamics.
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- 2022
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17. Ultra-thin rigid endoscope: Two-photon imaging through a graded-index multi-mode fiber
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Sivankutty, Siddharth, Andresen, Esben Ravn, Cossart, Rosa, Bouwmans, Géraud, Monneret, Serge, and Rigneault, Hervé
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Physics - Optics ,Physics - Instrumentation and Detectors - Abstract
Rigid endoscopes like graded-index (GRIN) lenses are known tools in biological imaging, but it is conceptually difficult to miniaturize them. In this letter, we demonstrate an ultra-thin rigid endoscope with a diameter of only 125 microns. In addition, we identify a domain where two-photon endoscopic imaging with fs-pulse excitation is possible. We validate the ultra-thin rigid endoscope consisting of a few cm of graded-index multi-mode fiber by using it to acquire optically sectioned two-photon fluorescence endoscopic images of three-dimensional samples., Comment: 17 pages, 15 figures, submitted to Opt. Express
- Published
- 2015
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18. State Residualisation and Kron Reduction for Model Order Reduction of Energy Systems
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Xianxian Zhao, Xavier Kestelyn, Quentin Cossart, Frédéric Colas, and Damian Flynn
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electromagnetic transient model ,phasor approximation ,model order reduction ,power system simulation ,grid-forming converters ,small-signal stability analysis ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Greater numbers of power electronics (PEs) converters are being connected to energy systems due to the development of renewable energy sources, high-voltage transmission, and PE-interfaced loads. Given that power electronics-based devices and synchronous machines have very different dynamic behaviours, some modelling approximations, which may commonly be applied to run transient simulations of transmission systems, may not be optimal for future grids. Indeed, the systematic utilisation of the phasor approximation for power lines, implemented in most transient simulation programs, is increasingly not appropriate anymore. In order to avoid the requirement for full electromagnetic transient simulations, which can be resource-demanding and time-consuming, this paper proposes a combination of an event-based state residualisation approximation and the Kron reduction technique. The proposed technique has the advantage of allowing accurate transient simulations based on the optimal reduction of the number of state variables, depending on the observed variables, the considered events, and the tolerated approximation error, along with simplifying power systems equations for accelerated simulations.
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- 2023
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19. The corona virus SARS-CoV-2 and the pandemic Covid19
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Cossart, Pascale
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Biology (General) ,QH301-705.5 - Published
- 2021
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20. Characteristic polyhedra of singularities without completion: part II
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Cossart, Vincent and Schober, Bernd
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- 2021
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21. Correction to: Characteristic polyhedra of singularities without completion: part II
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Cossart, Vincent and Schober, Bernd
- Published
- 2022
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22. Insect decline: immediate action is needed
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Jactel, Hervé, Imler, Jean-Luc, Lambrechts, Louis, Failloux, Anna-Bella, Lebreton, Jean Dominique, Maho, Yvon Le, Duplessy, Jean-Claude, Cossart, Pascale, and Grandcolas, Philippe
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Biodiversity ,Insect ,Decline ,Global change ,Conservation ,Biology (General) ,QH301-705.5 - Abstract
Insects appeared more than 400 million years ago and they represent the richest and most diverse taxonomic group with several million species. Yet, under the combined effect of the loss of natural habitats, the intensification of agriculture with massive use of pesticides, global warming and biological invasions, insects show alarming signs of decline. Although difficult to quantify, species extinction and population reductions are confirmed for many ecosystems. This results in a loss of services such as the pollination of plants, including food crops, the recycling of organic matter, the supply of goods such as honey and the stability of food webs. It is therefore urgent to halt the decline of Insects. We recommend implementing long-term monitoring of populations, tackling the causes of insect decline by reducing the use of synthetic insecticides, preserving natural habitats, and reinventing a positive relationship between humans and insects.
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- 2021
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23. Resolution of Singularities of Arithmetical Threefolds II
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Cossart, Vincent and Piltant, Olivier
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Mathematics - Algebraic Geometry - Abstract
We prove Grothendieck's Conjecture on Resolution of Singulari-ties for quasi-excellent schemes X of dimension three and of arbitrary characteristic. This applies in particular to X = SpecA, A a reduced complete Noetherian local ring of dimension three and to algebraic or arithmetical varieties of dimension three. Similarly, if F is a number field, a complete discretely valued field or more generally the quotient field of any excellent Dedekind domain O, any regular projective sur-face X/F has a proper and flat model X over O which is everywhere regular., Comment: updates and extends 'Resolution of Singularities of Arithmetical Threefolds I' posted on this website
- Published
- 2014
24. A strictly decreasing invariant for resolution of singularities in dimension two
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Cossart, Vincent and Schober, Bernd
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Mathematics - Algebraic Geometry - Abstract
We construct a local invariant for resolution of singularities of 2-dimensional excellent Noetherian schemes with boundary. We prove that the invariant strictly decreases at every step of the algorithm of Cossart, Jannsen and Saito., Comment: 41 pages, improved exposition, clarified minor details, added section of the termination of the CJS algorithm
- Published
- 2014
25. Characteristic polyhedra of singularities without completion -- Part II
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Cossart, Vincent and Schober, Bernd
- Subjects
Mathematics - Algebraic Geometry - Abstract
Hironaka's characteristic polyhedron is an important combinatorial object reflecting the local nature of a singularity. We prove that it can be determined without passing to the completion if the local ring is a G-ring and if additionally either it is Henselian, or a certain polynomiality condition $ (\mathrm{Pol}) $ holds, or a mild condition $(*) $ on the singularity holds. For example, the latter is fulfilled if the residue field is perfect., Comment: 46 pages; minor changes
- Published
- 2014
26. Benefits, challenges and contributors to the introduction of new hospital-based outpatient clinic pharmacist positions
- Author
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Centaine L. Snoswell, Amelia R. Cossart, Bernadette Chevalier, and Michael Barras
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Outpatient ,Pharmacists ,Qualitative research ,Interviews ,Specialist clinics ,Pharmacy and materia medica ,RS1-441 - Abstract
Background: Pharmacists working within interprofessional teams in the outpatient setting are well placed to address medication-related problems before and after hospital admission. Therefore, exploration of these roles is warranted. Objective(s): To explore pharmacists' and other health professionals' perspectives of the impact of pharmacists working within interprofessional teams in outpatient clinics. Furthermore, we endeavoured to identify both the challenges and contributors to success with the introduction of pharmacists into these settings. Methods: This qualitative study involved semi-structured interviews with both hospital outpatient clinic pharmacists and other clinic health professionals to gain an in-depth understanding of how the introduction of pharmacists into clinics impacted clinic processes, patient care, and relationships with other health professionals. Participants were recruited from the outpatient clinics who had recently added a pharmacist to their service. Participants involved in setting up the roles were invited to participate in a voluntary interview, the transcripts from which were analysed into themes and sub-themes using an inductive and deductive approach. Results: A total of 34 staff were interviewed of which 68% were female and 74% were aged between 31 and 50 years. The cohort included 16 outpatient pharmacists, nine pharmacist team leaders, five clinic nurses and four clinic doctors (specialist consultant or registrar). Three overall themes were identified: the benefits, the contributors, and the challenges of introducing clinical pharmacy services to outpatient clinics. When establishing a clinic role, pharmacists' awareness, adaptability, and strong communication were shown to be key traits to building rapport and trustworthiness with the established clinic team. Conclusions: When pharmacists are integrated into multidisciplinary outpatient clinics they and their colleagues believe that they provide benefits to the patients and the clinics. Decision makers need to be cognizant of factors that contribute to, as well as those that impede, the successful implementation of outpatient pharmacist roles.
- Published
- 2022
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27. Hippocampal hub neurons maintain distinct connectivity throughout their lifetime
- Author
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Marco Bocchio, Claire Gouny, David Angulo-Garcia, Tom Toulat, Thomas Tressard, Eleonora Quiroli, Agnès Baude, and Rosa Cossart
- Subjects
Science - Abstract
In the neonatal hippocampus, GABA cells born the earliest operate as ‘hubs’ by orchestrating population synchrony. Here, the authors show that the earliest born GABAergic cells in the hippocampal CA1 region maintain distinct anatomical and functional properties throughout their lifetime.
- Published
- 2020
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28. Impact of the gut microbiota on the m6A epitranscriptome of mouse cecum and liver
- Author
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Sabrina Jabs, Anne Biton, Christophe Bécavin, Marie-Anne Nahori, Amine Ghozlane, Alessandro Pagliuso, Giulia Spanò, Vincent Guérineau, David Touboul, Quentin Giai Gianetto, Thibault Chaze, Mariette Matondo, Marie-Agnès Dillies, and Pascale Cossart
- Subjects
Science - Abstract
The intestinal microbiota modulates host physiology and gene expression via unclear mechanisms. Here, Jabs et al. show that variations in the gut microbiota correlate with N6-methyladenosine modifications of host mRNAs in the cecum and liver of mice.
- Published
- 2020
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29. The in vivo ISGylome links ISG15 to metabolic pathways and autophagy upon Listeria monocytogenes infection
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Yifeng Zhang, Fabien Thery, Nicholas C. Wu, Emma K. Luhmann, Olivier Dussurget, Mariko Foecke, Clara Bredow, Daniel Jiménez-Fernández, Kevin Leandro, Antje Beling, Klaus-Peter Knobeloch, Francis Impens, Pascale Cossart, and Lilliana Radoshevich
- Subjects
Science - Abstract
ISG15 is a ubiquitin-like modifier that can be upregulated in response to bacterial infections. Here, the authors use proteomics to identify endogenous ISGylation substrates in the liver of Listeria monocytogenes infected mice and show that ISGylation alters basal and infection-induced autophagy.
- Published
- 2019
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30. CA1 pyramidal cell diversity is rooted in the time of neurogenesis
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Davide Cavalieri, Alexandra Angelova, Anas Islah, Catherine Lopez, Marco Bocchio, Yannick Bollmann, Agnès Baude, and Rosa Cossart
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Hippocampus ,Development ,Pyramidal cell ,Neuronal diversity ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Cellular diversity supports the computational capacity and flexibility of cortical circuits. Accordingly, principal neurons at the CA1 output node of the murine hippocampus are increasingly recognized as a heterogeneous population. Their genes, molecular content, intrinsic morpho-physiology, connectivity, and function seem to segregate along the main anatomical axes of the hippocampus. Since these axes reflect the temporal order of principal cell neurogenesis, we directly examined the relationship between birthdate and CA1 pyramidal neuron diversity, focusing on the ventral hippocampus. We used a genetic fate-mapping approach that allowed tagging three groups of age-matched principal neurons: pioneer, early-, and late-born. Using a combination of neuroanatomy, slice physiology, connectivity tracing, and cFos staining in mice, we show that birthdate is a strong predictor of CA1 principal cell diversity. We unravel a subpopulation of pioneer neurons recruited in familiar environments with remarkable positioning, morpho-physiological features, and connectivity. Therefore, despite the expected plasticity of hippocampal circuits, given their role in learning and memory, the diversity of their main components is also partly determined at the earliest steps of development.
- Published
- 2021
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31. Dealing with Uncertainty in Situation Assessment: towards a Symbolic Approach
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Castel, Charles, Cossart, Corine, and Tessier, Catherine
- Subjects
Computer Science - Artificial Intelligence - Abstract
The situation assessment problem is considered, in terms of object, condition, activity, and plan recognition, based on data coming from the real-word {em via} various sensors. It is shown that uncertainty issues are linked both to the models and to the matching algorithm. Three different types of uncertainties are identified, and within each one, the numerical and the symbolic cases are distinguished. The emphasis is then put on purely symbolic uncertainties: it is shown that they can be dealt with within a purely symbolic framework resulting from a transposition of classical numerical estimation tools., Comment: Appears in Proceedings of the Fourteenth Conference on Uncertainty in Artificial Intelligence (UAI1998)
- Published
- 2013
32. Invariance of Hironaka’s characteristic polyhedron
- Author
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Cossart, Vincent, Jannsen, Uwe, and Schober, Bernd
- Published
- 2019
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33. Existence des diviseurs dicritiques, d'apr\`es S.S.Abhyankar
- Author
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Cossart, Vincent, Matusinski, Mickaël, and Moreno-Socias, Guillermo
- Subjects
Mathematics - Algebraic Geometry - Abstract
In geometric terms, given a singular foliation of the plane, a dicritical divisor is (whenever it exists) an irreducible component of the exceptional divisor which is transverse to the foliation. Abhyankar gave recently a definition of the dicritical divisors which generalize and algebraicize the geometrical definition in the local case and the polynomial case. Following his work, we give a geometrical interpretation of these dicritical divisors and new proofs of their existence., Comment: 9 pages, in French
- Published
- 2012
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34. Characteristic polyhedra of singularities without completion
- Author
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Cossart, Vincent and Piltant, Olivier
- Subjects
Mathematics - Algebraic Geometry - Abstract
Let $(R,M,k)$ be a regular local G-ring with regular system of parameters $(u_1, \ldots ,u_d,y)$. We prove that the Hironaka characteristic polyhedron $\Delta (f;u_1, \ldots ,u_d)$, $f \not \in (u_1, \ldots ,u_d)$ of a hypersurface singularity $X={\rm Spec}R/(f)$ can be computed in some system of coordinates belonging to $R$. No assumption on the residue characteristic is required.
- Published
- 2012
35. Dicritical divisors after S.S. Abhyankar et I. Luengo
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Cossart, Vincent and Matusinski, Mickaël
- Subjects
Mathematics - Commutative Algebra ,Mathematics - Algebraic Geometry - Abstract
In [AL11], S.S Abhyankar and I. Luengo introduce a new theory of dicritical divisors in the most general framework. Here we simplify and generalize their results (see Theorems 3.1 and 3.2).
- Published
- 2011
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36. Se référer au passé pour faire du communalisme une alternative émancipatrice
- Author
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Paula Cossart
- Subjects
Bookchin ,Wright ,real utopias ,communalism ,anarchy ,history ,Philosophy (General) ,B1-5802 ,Sociology (General) ,HM401-1281 - Abstract
We are interested here in libertarian writings that make the past a reserve of experiences likely to inspire a more just society, by focusing our attention on the valuations of the commune, understood as a grouping on a territorial basis of individuals self-managing in general assembly. We then question the writings of Murray Bookchin with a focus on the emancipatory role of real utopia, as put forward by Erik Olin Wright. Starting from the plea developed by the latter in favour of the adoption, by researchers in particular, of a posture of uncomplicated utopianism opening up the field of democratic possibilities, we question the relationship between anarchy, utopia and history, by analysing Bookchin's work in a new light. We begin by returning to the implications of Wright's posture : to make known the actual functioning of various alternative experiments, the social sciences being distinguished in this respect from purely imaginary utopian narratives. We then show that the relationship of some anarchist authors to utopia is close to this perspective. Based on an analysis of Bookchin's writings, we show that communalism constitutes a more powerful real utopia than those to which Wright refers. While Wright's approach is presentist, Bookchin's reference to the past allows him to go further. His view of history is rich in lessons for the development of a true democracy in the form of communalism today.
- Published
- 2021
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37. « Le Morvan est-il maudit ? », analyse géographique d’un territoire hyper-rural
- Author
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Étienne Cossart
- Subjects
deep-rurality ,countryside ,retraction ,associations ,Morvan ,Burgundy ,Geography (General) ,G1-922 - Abstract
The Morvan is a deep-rural territory on which studies have generally focused on the repulsive character. In line with recent reflections on deep-rural territories we try to take a more nuanced look at this territory through a geographical analysis. A spatial analysis allows us to compare the demographic and agricultural trajectories of the Morvan communes with those of the whole of the former Burgundy region. Both demographic decline and retraction of agricultural activities exhibit complex temporal patterns. To complement, an emic approach allows us to observe the emergence of singular dynamics to compensate for the decline in the supply of public services: these are hybrid systems involving local public actors with initiatives from the inhabitants, most often in an associative framework. The associative fabric is significantly denser than in the rest of the former Burgundy region. On the one hand, it is indicative of a dynamic system of actors, in contrast to the sluggish image of hyper-rural territories. On the other hand, it also reveals the disengagement of public authorities from fundamental services.
- Published
- 2021
38. Pharmacokinetic and Pharmacodynamic Considerations in Relation to Calcineurin Usage in Elderly Kidney Transplant Recipients
- Author
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Amelia R. Cossart, Nicole M. Isbel, Carla Scuderi, Scott B. Campbell, and Christine E. Staatz
- Subjects
kidney ,transplantation ,calcineurin inbibitors ,elderly ,immunosuppression ,pharmacokinetics ,Therapeutics. Pharmacology ,RM1-950 - Abstract
This review summarizes how possible age-related changes in tacrolimus and cyclosporine pharmacokinetics and pharmacodynamics may influence drug dosing and monitoring in the elderly, and highlights how micro-sampling may be useful in this cohort in the future. Advancing biological age leads to physiological changes that can affect drug absorption, distribution, metabolism and excretion, as well as immune system responsiveness. Some studies have shown that elderly recipients may have higher dose-adjusted exposure and/or lower clearance of the calcineurin inhibitors, suggesting that doses may need to be lowered in elderly recipients. Only one study has examined how aging effects drug target enzyme activity and demonstrated that age does not correlate with the calcineurin inhibitor half-maximal inhibitory concentration. Several studies have shown elderly kidney transplant recipients have increased risk of both morbidity and mortality, compared to younger adults due to increased susceptibility to immunosuppressant side effects, particularly cardiovascular disease, infection and malignancy. Current immunosuppressant dosing and monitoring protocols often make no adjustments for age. Lower maintenance immunosuppressant targets in elderly recipients may decrease patient susceptibility to drug side effects, however, further studies are required and appropriate targets need to be established. Blood draw by micro-sampling may be useful for drug monitoring in this cohort in the future, as blood collection is minimally invasive and less painful than venepuncture. Micro-sampling could also make further pharmacokinetic, pharmacodynamics and outcome studies in the elderly more feasible.
- Published
- 2021
- Full Text
- View/download PDF
39. La biologie à l’Académie des sciences
- Author
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Bach, Jean François and Cossart, Pascale
- Subjects
Biology (General) ,QH301-705.5 - Published
- 2020
- Full Text
- View/download PDF
40. Canonical embedded and non-embedded resolution of singularities for excellent two-dimensional schemes
- Author
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Cossart, Vincent, Jannsen, Uwe, and Saito, Shuji
- Subjects
Mathematics - Algebraic Geometry ,Mathematics - Commutative Algebra ,14J17, 14E15 - Abstract
We prove the existence of resolution of singularities for arbitrary (not necessarily reduced or irreducible) excellent two-dimensional schemes, via permissible blow-ups. The resolution is canonical, and functorial with respect to automorphisms or etale or Zariski localizations. We treat the embedded case as well as the non-embedded case, with or without a boundary, and we relate the diferent versions. In the non-embedded case, a boundary is a collection of locally principal closed subschemes. Our main tools are the stratifications by Hilbert-Samuel functions and the characteristic polyhedra introduced by H. Hironaka. In an appendix we show that the standard method used in characteristic zero - the theory of maximal contact - does not work for surfaces in positive characteristic (the counterexamples are hypersurfaces in affine threespace and work over any field of positive characteristic). In this new version, we treat the case of locally noetherian but not necessarily noetherian schemes in an appropriate way. Here one does not have a finite resolution sequence, but still a canonical resolution morphism by glueing. The same techniques allow to treat algebraic spaces and stacks., Comment: 169 pages, 3 figures
- Published
- 2009
41. Comparison of Widely Used Listeria monocytogenes Strains EGD, 10403S, and EGD-e Highlights Genomic Differences Underlying Variations in Pathogenicity
- Author
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Bécavin, Christophe, Bouchier, Christiane, Lechat, Pierre, Archambaud, Cristel, Creno, Sophie, Gouin, Edith, Wu, Zongfu, Kühbacher, Andreas, Brisse, Sylvain, Pucciarelli, M Graciela, Portillo, Francisco García-del, Hain, Torsten, Portnoy, Daniel A, Chakraborty, Trinad, Lecuit, Marc, Pizarro-Cerdá, Javier, Moszer, Ivan, Bierne, Hélène, and Cossart, Pascale
- Subjects
Microbiology ,Biological Sciences ,Genetics ,Digestive Diseases ,Biotechnology ,Foodborne Illness ,Biodefense ,Emerging Infectious Diseases ,Infectious Diseases ,2.2 Factors relating to the physical environment ,2.1 Biological and endogenous factors ,Infection ,Animals ,Blood ,DNA ,Bacterial ,Disease Models ,Animal ,Genetic Variation ,Genome ,Bacterial ,Humans ,Listeria monocytogenes ,Listeriosis ,Liver ,Mice ,Mice ,Inbred BALB C ,Molecular Sequence Data ,Sequence Analysis ,DNA ,Spleen ,Virulence ,Biochemistry and cell biology ,Medical microbiology - Abstract
For nearly 3 decades, listeriologists and immunologists have used mainly three strains of the same serovar (1/2a) to analyze the virulence of the bacterial pathogen Listeria monocytogenes. The genomes of two of these strains, EGD-e and 10403S, were released in 2001 and 2008, respectively. Here we report the genome sequence of the third reference strain, EGD, and extensive genomic and phenotypic comparisons of the three strains. Strikingly, EGD-e is genetically highly distinct from EGD (29,016 single nucleotide polymorphisms [SNPs]) and 10403S (30,296 SNPs), and is more related to serovar 1/2c than 1/2a strains. We also found that while EGD and 10403S strains are genetically very close (317 SNPs), EGD has a point mutation in the transcriptional regulator PrfA (PrfA*), leading to constitutive expression of several major virulence genes. We generated an EGD-e PrfA* mutant and showed that EGD behaves like this strain in vitro, with slower growth in broth and higher invasiveness in human cells than those of EGD-e and 10403S. In contrast, bacterial counts in blood, liver, and spleen during infection in mice revealed that EGD and 10403S are less virulent than EGD-e, which is itself less virulent than EGD-e PrfA*. Thus, constitutive expression of PrfA-regulated virulence genes does not appear to provide a significant advantage to the EGD strain during infection in vivo, highlighting the fact that in vitro invasion assays are not sufficient for evaluating the pathogenic potential of L. monocytogenes strains. Together, our results pave the way for deciphering unexplained differences or discrepancies in experiments using different L. monocytogenes strains. IMPORTANCE Over the past 3 decades, Listeria has become a model organism for host-pathogen interactions, leading to critical discoveries in a broad range of fields, including bacterial gene regulation, cell biology, and bacterial pathophysiology. Scientists studying Listeria use primarily three pathogenic strains: EGD, EGD-e, and 10403S. Despite many studies on EGD, it is the only one of the three strains whose genome has not been sequenced. Here we report the sequence of its genome and a series of important genomic and phenotypic differences between the three strains, in particular, a critical mutation in EGD's PrfA, the main regulator of Listeria virulence. Our results show that the three strains display differences which may play an important role in the virulence differences observed between the strains. Our findings will be of critical relevance to listeriologists and immunologists who have used or may use Listeria as a tool to study the pathophysiology of listeriosis and immune responses.
- Published
- 2014
42. Comparison of widely used Listeria monocytogenes strains EGD, 10403S, and EGD-e highlights genomic variations underlying differences in pathogenicity.
- Author
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Bécavin, Christophe, Bouchier, Christiane, Lechat, Pierre, Archambaud, Cristel, Creno, Sophie, Gouin, Edith, Wu, Zongfu, Kühbacher, Andreas, Brisse, Sylvain, Pucciarelli, M Graciela, García-del Portillo, Francisco, Hain, Torsten, Portnoy, Daniel A, Chakraborty, Trinad, Lecuit, Marc, Pizarro-Cerdá, Javier, Moszer, Ivan, Bierne, Hélène, and Cossart, Pascale
- Subjects
Liver ,Spleen ,Blood ,Animals ,Mice ,Inbred BALB C ,Humans ,Mice ,Listeria monocytogenes ,Disease Models ,Animal ,DNA ,Bacterial ,Sequence Analysis ,DNA ,Virulence ,Genome ,Bacterial ,Molecular Sequence Data ,Genetic Variation ,Listeriosis ,Inbred BALB C ,Disease Models ,Animal ,DNA ,Bacterial ,Sequence Analysis ,Genome ,Microbiology - Abstract
For nearly 3 decades, listeriologists and immunologists have used mainly three strains of the same serovar (1/2a) to analyze the virulence of the bacterial pathogen Listeria monocytogenes. The genomes of two of these strains, EGD-e and 10403S, were released in 2001 and 2008, respectively. Here we report the genome sequence of the third reference strain, EGD, and extensive genomic and phenotypic comparisons of the three strains. Strikingly, EGD-e is genetically highly distinct from EGD (29,016 single nucleotide polymorphisms [SNPs]) and 10403S (30,296 SNPs), and is more related to serovar 1/2c than 1/2a strains. We also found that while EGD and 10403S strains are genetically very close (317 SNPs), EGD has a point mutation in the transcriptional regulator PrfA (PrfA*), leading to constitutive expression of several major virulence genes. We generated an EGD-e PrfA* mutant and showed that EGD behaves like this strain in vitro, with slower growth in broth and higher invasiveness in human cells than those of EGD-e and 10403S. In contrast, bacterial counts in blood, liver, and spleen during infection in mice revealed that EGD and 10403S are less virulent than EGD-e, which is itself less virulent than EGD-e PrfA*. Thus, constitutive expression of PrfA-regulated virulence genes does not appear to provide a significant advantage to the EGD strain during infection in vivo, highlighting the fact that in vitro invasion assays are not sufficient for evaluating the pathogenic potential of L. monocytogenes strains. Together, our results pave the way for deciphering unexplained differences or discrepancies in experiments using different L. monocytogenes strains. IMPORTANCE Over the past 3 decades, Listeria has become a model organism for host-pathogen interactions, leading to critical discoveries in a broad range of fields, including bacterial gene regulation, cell biology, and bacterial pathophysiology. Scientists studying Listeria use primarily three pathogenic strains: EGD, EGD-e, and 10403S. Despite many studies on EGD, it is the only one of the three strains whose genome has not been sequenced. Here we report the sequence of its genome and a series of important genomic and phenotypic differences between the three strains, in particular, a critical mutation in EGD's PrfA, the main regulator of Listeria virulence. Our results show that the three strains display differences which may play an important role in the virulence differences observed between the strains. Our findings will be of critical relevance to listeriologists and immunologists who have used or may use Listeria as a tool to study the pathophysiology of listeriosis and immune responses.
- Published
- 2014
43. The cryo-electron microscopy supramolecular structure of the bacterial stressosome unveils its mechanism of activation
- Author
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Allison H. Williams, Adam Redzej, Nathalie Rolhion, Tiago R. D. Costa, Aline Rifflet, Gabriel Waksman, and Pascale Cossart
- Subjects
Science - Abstract
The bacterial stressosome is a large nanomachine and a key inducer of stress response. Here, the authors present the cryo-EM structure of the stressosome from the bacterial pathogen Listeria monocytogenes at 3.38 Å resolution and discuss its activation mechanism.
- Published
- 2019
- Full Text
- View/download PDF
44. Role of Endothelial Cell Septin 7 in the Endocytosis of Candida albicans
- Author
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Phan, Quynh T, Eng, David K, Mostowy, Serge, Park, Hyunsook, Cossart, Pascale, and Filler, Scott G
- Subjects
Infectious Diseases ,2.1 Biological and endogenous factors ,2.2 Factors relating to the physical environment ,Aetiology ,Actins ,Antigens ,CD ,Cadherins ,Candida albicans ,Cell Adhesion ,Cell Cycle Proteins ,Cells ,Cultured ,Endocytosis ,Endothelial Cells ,Fungal Proteins ,Humans ,Hyphae ,Protein Binding ,Protein Multimerization ,Septins ,Microbiology - Abstract
UnlabelledCandida albicans invades endothelial cells by binding to N-cadherin and other cell surface receptors. This binding induces rearrangement of endothelial cell actin microfilaments, which results in the formation of pseudopods that surround the organism and pull it into the endothelial cell. Here, we investigated the role of endothelial cell septin 7 (SEPT7) in the endocytosis of C. albicans hyphae. Using confocal microscopy, we determined that SEPT7 accumulated with N-cadherin and actin microfilaments around C. albicans as it was endocytosed by endothelial cells. Affinity purification studies indicated that a complex containing N-cadherin and SEPT7 was recruited by C. albicans and that formation of this complex around C. albicans was mediated by the fungal Als3 and Ssa1 invasins. Knockdown of N-cadherin by small interfering RNA (siRNA) reduced recruitment of SEPT7 to C. albicans, suggesting that N-cadherin functions as a link between SEPT7 and the fungus. Also, depolymerization of actin microfilaments with cytochalasin D decreased the association between SEPT7 and N-cadherin and inhibited recruitment of both SEPT7 and N-cadherin to C. albicans, indicating the necessity of an intact cytoskeleton in the functional interaction between SEPT7 and N-cadherin. Importantly, knockdown of SEPT7 decreased accumulation of N-cadherin around C. albicans in intact endothelial cells and reduced binding of N-cadherin to this organism, as revealed by the affinity purification assay. Furthermore, SEPT7 knockdown significantly inhibited the endocytosis of C. albicans. Therefore, in response to C. albicans infection, SEPT7 forms a complex with endothelial cell N-cadherin, is required for normal accumulation of N-cadherin around C. albicans hyphae, and is necessary for maximal endocytosis of the organism.ImportanceDuring hematogenously disseminated infection, Candida albicans invades the endothelial cell lining of the blood vessels to invade the deep tissues. C. albicans can invade endothelial cells by inducing its own endocytosis, which is triggered when the C. albicans Als3 and Ssa1 invasins bind to N-cadherin on the endothelial cell surface. How this binding induces endocytosis is incompletely understood. Septins are intracellular GTP-binding proteins that influence the function and localization of cell surface proteins. We found that C. albicans Als3 and Ssa1 bind to a complex containing N-cadherin and septin 7, which in turn interacts with endothelial cell microfilaments, thereby inducing endocytosis of the organism. The key role of septin 7 in governing receptor-mediated endocytosis is likely relevant to host cell invasion by other microbial pathogens, in addition to C. albicans.
- Published
- 2013
45. Manipulation of ultracold atomic mixtures using microwave techniques
- Author
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Ciampini, D., Courtade, E., Sias, C., Cossart, D., Carelli, G., Mango, F., Morsch, O., and Arimondo, E.
- Subjects
Physics - Atomic Physics - Abstract
We used microwave radiation to evaporatively cool a mixture of of 133Cs and 87Rb atoms in a magnetic trap. A mixture composed of an equal number (around 10^4) of Rb and Cs atoms in their doubly polarized states at ultracold temperatures was prepared. We also used microwaves to selectively evaporate atoms in different Zeeman states., Comment: 9 pages, 6 figures
- Published
- 2004
46. Sympathetic cooling and collisional properties of a Rb-Cs mixture
- Author
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Anderlini, M., Courtade, E., Cristiani, M., Cossart, D., Ciampini, D., Sias, C., Morsch, O., and Arimondo, E.
- Subjects
Condensed Matter - Soft Condensed Matter - Abstract
We report on measurements of the collisional properties of a mixture of $^{133}$Cs and $^{87}$Rb atoms in a magnetic trap at $\mu\mathrm{K}$ temperatures. By selectively evaporating the Rb atoms using a radio-frequency field, we achieved sympathetic cooling of Cs down to a few $\mu\mathrm{K}$. The inter-species collisional cross-section was determined through rethermalization measurements, leading to an estimate of $a_s=595 a_0$ for the s-wave scattering length for Rb in the $|F=2, m_F=2>$ and Cs in the $|F=4, m_F=4>$ magnetic states. We briefly speculate on the prospects for reaching Bose-Einstein condensation of Cs inside a magnetic trap through sympathetic cooling.
- Published
- 2004
- Full Text
- View/download PDF
47. La dynamique d’enfrichement, ses expressions paysagères et ses significations : le cas du Beaujolais viticole
- Author
-
Jessica Pic, Yoann Le Guen, Étienne Cossart, and Mathieu Fressard
- Subjects
agricultural abandoned plots ,vineyard ,impact on the landscape ,socio-economic factors ,Beaujolais (France) ,Environmental sciences ,GE1-350 - Abstract
The economic crisis that affects the Beaujolais vineyard since the late 1990s is the origin of the abandonment of previously vine-growing plots. It implies important landscape mutations, worrying the local stakeholders. The lack of definition of these abandoned plots, as well as the technical difficulty to qualify and quantify the conversion dynamics, is a problem to hold back the conversion from agricultural to abandoned plots. Photo-interpretation combined with fieldwork and interviews of stakeholders was conducted to characterize the extension and spatial patterns of abandoned plots. It was done for three catchments to compare the results and highlight the underlying ways and means of the conversion of vine into abandoned plots. A typology was built : it includes six types of abandoned plots, each one having, according to its features, its own impact on the landscape. Three temporal filiations between the types were identified : one is located on the hillside, one is in the plain, but the previous vine stocks have been uprooted, and one is in the plain and the vine stocks have not been uprooted. The conversion into abandoned plots was quantified and related with the vine plots extent of the catchments in 1999 : 1.5 % of the vine plots surface that has been converted into abandoned plots for the Lower Ardières catchment, 8.4 % for the Marverand catchment and 8.7 % for the Merloux catchment. A distinction between north and south Beaujolais has been noticed, highlighting the slope and the vintage sorting influence on the abandonment but also of land withholding phenomena.
- Published
- 2020
- Full Text
- View/download PDF
48. Clathrin phosphorylation is required for actin recruitment at sites of bacterial adhesion and internalization
- Author
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Bonazzi, Matteo, Vasudevan, Lavanya, Mallet, Adeline, Sachse, Martin, Sartori, Anna, Prevost, Marie-Christine, Roberts, Allison, Taner, Sabrina B, Wilbur, Jeremy D, Brodsky, Frances M, and Cossart, Pascale
- Subjects
1.1 Normal biological development and functioning ,2.2 Factors relating to the physical environment ,Underpinning research ,Aetiology ,Infection ,Actins ,Bacterial Adhesion ,Bacterial Proteins ,Cells ,Cultured ,Clathrin ,Coated Pits ,Cell-Membrane ,HeLa Cells ,Host-Pathogen Interactions ,Humans ,Listeria ,Microscopy ,Fluorescence ,Phosphorylation ,Receptors ,Cell Surface ,Transfection ,Tyrosine ,Hela Cells ,Biological Sciences ,Medical and Health Sciences ,Developmental Biology - Abstract
Bacterial pathogens recruit clathrin upon interaction with host surface receptors during infection. Here, using three different infection models, we observed that host-pathogen interactions induce tyrosine phosphorylation of clathrin heavy chain. This modification was critical for recruitment of actin at bacteria-host adhesion sites during bacterial internalization or pedestal formation. At the bacterial interface, clathrin assembled to form coated pits of conventional size. Because such structures cannot internalize large particles such as bacteria, we propose that during infection, clathrin-coated pits serve as platforms to initiate actin rearrangements at bacteria-host adhesion sites. We then showed that the clathrin-actin interdependency is initiated by Dab2 and depends on the presence of clathrin light chain and its actin-binding partner Hip1R, and that the fully assembled machinery can recruit Myosin VI. Together, our study highlights a physiological role for clathrin heavy chain phosphorylation and reinforces the increasingly recognized function of clathrin in actin cytoskeletal organization in mammalian cells.
- Published
- 2011
49. Listeria monocytogenes Exploits Mitochondrial Contact Site and Cristae Organizing System Complex Subunit Mic10 To Promote Mitochondrial Fragmentation and Cellular Infection
- Author
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Filipe Carvalho, Anna Spier, Thibault Chaze, Mariette Matondo, Pascale Cossart, and Fabrizia Stavru
- Subjects
Listeria monocytogenes ,MICOS complex ,Mic10 ,mitochondrial fission ,proteomics ,Microbiology ,QR1-502 - Abstract
ABSTRACT Mitochondrial function adapts to cellular demands and is affected by the ability of the organelle to undergo fusion and fission in response to physiological and nonphysiological cues. We previously showed that infection with the human bacterial pathogen Listeria monocytogenes elicits transient mitochondrial fission and a drop in mitochondrion-dependent energy production through a mechanism requiring the bacterial pore-forming toxin listeriolysin O (LLO). Here, we performed quantitative mitochondrial proteomics to search for host factors involved in L. monocytogenes-induced mitochondrial fission. We found that Mic10, a critical component of the mitochondrial contact site and cristae organizing system (MICOS) complex, is significantly enriched in mitochondria isolated from cells infected with wild-type but not with LLO-deficient L. monocytogenes. Increased mitochondrial Mic10 levels did not correlate with upregulated transcription, suggesting a posttranscriptional mechanism. We then showed that Mic10 is necessary for L. monocytogenes-induced mitochondrial network fragmentation and that it contributes to L. monocytogenes cellular infection independently of MICOS proteins Mic13, Mic26, and Mic27. In conclusion, investigation of L. monocytogenes infection allowed us to uncover a role for Mic10 in mitochondrial fission. IMPORTANCE Pathogenic bacteria can target host cell organelles to take control of key cellular processes and promote their intracellular survival, growth, and persistence. Mitochondria are essential, highly dynamic organelles with pivotal roles in a wide variety of cell functions. Mitochondrial dynamics and function are intimately linked. Our previous research showed that Listeria monocytogenes infection impairs mitochondrial function and triggers fission of the mitochondrial network at an early infection stage, in a process that is independent of the presence of the main mitochondrial fission protein Drp1. Here, we analyzed how mitochondrial proteins change in response to L. monocytogenes infection and found that infection raises the levels of Mic10, a mitochondrial inner membrane protein involved in formation of cristae. We show that Mic10 is important for L. monocytogenes-dependent mitochondrial fission and infection of host cells. Our findings thus offer new insight into the mechanisms used by L. monocytogenes to hijack mitochondria to optimize host infection.
- Published
- 2020
- Full Text
- View/download PDF
50. Introduction: The New England Town Meeting: A Founding Myth of American Democracy
- Author
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Andrea Felicetti, James T. Kloppenberg, and Paula Cossart
- Subjects
New England Town Meeting ,Political theory ,JC11-607 - Abstract
Notwithstanding notable exceptions, historical investigation is far from central in deliberative scholarship and even recent work on participatory research stresses the need for more historical work. The aim of our introduction to this collective volume is to assess and to draw attention to the contribution of historical analysis in the current scholarly debate on democracy, in particular regarding the ways in which participation and deliberation emerge and develop in New England’s famous town meetings. Town meetings have traditionally been cited as one of the fullest and earliest realizations of the idea of democratic government and of deliberation at work. Nowadays the great debate on deliberative and participatory democracy has contributed to restoring the town meetings as a symbol of democratic deliberation. The critical study of how one of the oldest and most inspiring forms of democratic participation has evolved is not only a fascinating endeavor in itself, it is also a unique opportunity to better understand how and to what extent these institutional practices, inspired by ideals of deliberation and participation, can support – or impede – the democratization of today’s societies.
- Published
- 2019
- Full Text
- View/download PDF
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