Aix-Marseille Université
  • Marseille, France
Recent publications
Biological dinitrogen (N 2 ) fixation is meagrely explored in the Bay of Bengal (Bay). Stratified, warm, oligotrophic (but relatively high iron and phosphate) and oxygen minimum zone (OMZ) waters of the Bay might be a niche for diazotrophs. Therefore, we conducted N 2 fixation rate measurements during the spring inter‐monsoon in the euphotic zone, the OMZ and below the OMZ down to 1500 m depth near the coastal and in the central Bay. We further assessed primary production and cyanobacterial community composition along with their potential environmental controlling parameters. N 2 fixation rates in the euphotic zone were low (0.02 to 0.38 nmol N L ⁻¹ d ⁻¹ ) and their contribution to primary production was small (< 2%). Despite conducive conditions for diazotrophy in the Bay, the reason for the relatively low euphotic zone and OMZ N 2 fixation rates remained unclear and enigmatic. Interestingly, significantly higher N 2 fixation rates occurred below the OMZ (> 600 m depth), ranging from 0.06 to 0.11 nmol N L ⁻¹ d ⁻¹ where oxygen concentrations ranged between 0.5 and 1.6 mL L ⁻¹ , rather than within the OMZ where rates ranged from 0.02 to 0.08 nmol N L ⁻¹ d ⁻¹ and oxygen concentrations were ≤ 0.5 mL L ⁻¹ . Euphotic zone N 2 fixation showed seasonality in the Bay with increasing rates from spring to summer season, perhaps owing to increasing Fe flux as the summer monsoon approaches its peak.
  • Émile Deléage
    Émile Deléage
We show that the Reynolds averaged equations for compressible fluids (neglecting third order correlations) are well‐posed in Hs$$ {H}^s $$ when the pressure vanishes in dimensions d=2$$ d=2 $$ and 3. In order to do this, we show that the system is Friedrichs‐symmetrizable. This model belongs to the class of non‐conservative hyperbolic systems. Hence the usual symmetrisation method for conservation laws can not be used here.
Many readers wondering about the relation between Hollinghurst’s novel and illness will readily think of AIDS, the illness that kills two of Nick Guest’s lovers, while Nick goes through the 1980s discovering the life of the well-off from his unacknowledged position of marginality. AIDS is the illness that brings about a certain vision of the body and creates a sense of unease and realism to the text. However, one character shouldn’t be neglected: Catherine, the Feddens’ daughter, whom Nick befriends straightaway. Catherine is said to be manic-depressive, a common diagnosis of the 1980s, after multiple attempts at self-harming. This secondary character enables the author to analyse the behavioural symptoms that set her as a pathological figure, but she can structurally be placed alongside the troubles experienced by some gay men in the novel and illuminate them. Hollinghurst finds in Catherine a way of rending the veil of literary propriety and the traditional template of the comedy of manners in order to question how a subject can be overwhelmed when they are assigned to a medical identification that is so strict that it becomes mortifying.
Doris Lessing’s The Fifth Child explores the question of disability and the subjective experience of having a son who, for lack of medical help, remains an enigma. The fifth child of a couple immediately possesses the qualities of a misfit, without ever being clearly diagnosed. Quite rapidly, this last child is the agent of a split in the family. The novel interestingly approaches the body of both mother and son as a site of pleasure and pain, strength and weakness, both a physical and psychic reality. The fifth child will inevitably come to stand for the punishment the family must face for indulging in the excessive pleasure of begetting and parenting. What this chapter explores is the subjective companionship of mother and son not as pathological but, on the contrary, as the condition for each of them to survive and perhaps even for Harriet to exist. By locating her son’s symptom at the place where she fails to be a mother, Harriet ensures that even more than her other children, Ben should be regarded as the epitome of the jouissance she craves for: an unbridled body marked by no self-consciousness.
Pat Barker’s Trilogy evidently replays some of the themes contained in Mrs Dalloway, if only because both novels focus on the trauma of World War I. After showing how the Freudian influence plays a role in the psychiatrist’s handling of his patients’ symptoms, notably by offering an interpretative model that the patients mock, I argue that Prior, the only entirely fictional character, provides Rivers with a new way of approaching the symptom his patient suffers from. This new method results in great improvement: not only is Prior stripped of the symptom that most impeded him at first—mutism—but he also becomes a diarist, writing becoming a way for him to find his voice well beyond the reductive speech acts that he is capable to produce when in hospital. Behavioural therapy might have enabled him to speak again, but without questioning the subject’s place in discourse and in relation to others, therapy would have rendered Prior’s use of language inefficient. Prior in fact becomes more in control of his symptoms when the logic of his choice of sexual partners is more apparent and he can form relationships he could only look at with irony before.
This chapter offers a revision of the links between literature and madness by addressing the ideological framework of mental health specialists and cures. In particular, it addresses the difference in the handling of ‘symptom formations’ both within psychiatric disciplines and in psychoanalysis, suggesting that the way literature deals with symptomatic formations goes beyond questions of understanding or comprehension. Based on an interpretation of Virginia Woolf’s ‘On Being Ill’ essay, the chapter traces ways in which literature enters the theoretical debates around the notions of care and therapy. Woolf’s essay suggests that the state of being ill should not be obliterated or considered to be a condition to annihilate. On the contrary, she equates it with a heightened sense of being that corresponds to Lacan’s late theorisation of the symptom as that which needs to be preserved and which is key to a subjective response. Therefore, the symptom may not need to be cured but to be cared for instead.
This chapter looks at new symptoms for subjects seeking forms of attachment in contemporary Britain. Ali Smith’s Seasonal Quartet was written during and in the wake of the campaign for Brexit and in it she conveys her analysis of the more profound fractures within society this political agenda led to, enhanced or was the consequence of. In addition, the novels cover the Covid pandemic that obviously had not been anticipated, except thematically in the questions raised about ageing, illness and death. The novels were published very recently; thus, they enable us to momentarily stop and reflect upon a century of literary productions that began with the publication of Mrs Dalloway. They also enable us to raise questions about new ways of writing the psyche in an age that would like to reduce subjects to consumers, critical thinkers to gullible and non-ideological persons, communitarians to dangers and so forth. While society seems to pit people against one another because of age, sex, class and aspirations, Ali Smith allows them to create their own response in a language characterised by lack of cohesion, lack of correction and stability, a language that is therefore and perhaps like all social productions mad.
This chapter studies Mrs Dalloway as a prime example of the way in which approaching the symptom as that which must be preserved infers new ways of interpreting the role of the patient in novels focusing on mental disorders. Septimus Warren Smith features as perhaps one of the last ‘delirious’ patients in British fiction. The doctors think Septimus is pathologically silent and unable to act; yet Septimus keeps speaking to himself, and his wife tries to ensure that he does not, by interrupting him constantly. I argue that this is the symptom that needs focusing on: Septimus’s silence is a very singular, subjective response to a world that he feels estranged from. The chapter delves into the repressive causality that bars access to an interpretation of the symptom that would be more structural than meaningful. By showing how the symptom not solely is to be interpreted but can also be read as a meaningless formation evocative of a peculiar response to the world, the discourse of psychiatry is not only defeated and satirised but also presented as requiring a reform—which is exactly what Richard Dalloway and Sir Bradshaw want to do, although they remain unaware of this.
In the history of British writings about psychiatry, McGrath’s novels are another landmark that has surprisingly led to very little critical interest in recent years. The psychiatrist depicted in Asylum is a mock detective because he seeks to make psychiatric symptoms speak, searching for a causality that would be indisputable. His authority derives from his method, in which the meaning of the patients’ symptoms is forced upon the subject’s story. In his treatment of Stella, Dr Cleave’s method fails, however, because he wants her silence to be the sign of something else. The text instead reveals that it is impossible for her to articulate her own story in a dialectical fashion, making her incapable of appropriating the story the psychiatrist elaborates on her behalf. McGrath’s text shows an evolution from the template of satire set by Woolf: the repressive hypothesis of the Freudian unconscious, even if the story is set in the 1950s, no longer holds in the 1990s, and the author’s choice of various stories superimposing proves an efficient strategy in order to better camouflage the absence of his main protagonist’s story, ironically called Stella.
In Cusk’s trilogy, silence is again treated as a symptomatic formation. In the ‘aftermath’ of publishing a trilogy composed of Outline (2014), Transit (2016) and Kudos (2018), Cusk claims that she had been reduced to creative silence after her memoir about the end of her marriage, Aftermath. What Cusk describes situates her in a Modernist tradition that foregrounds the crisis and failure of meaning and communication that writing tries to stitch up. Inevitably, Woolf scholars will find in Cusk’s reflection a reminder of Woolf’s similar anxiety about, and drive towards, silence—the much-quoted sentence of Woolf’s first novel (‘I want to write a novel about silence, the things people don’t say. But the difficulty is immense’ (VO, 232)) is bound to resonate with Cusk’s novels. For it is very paradoxical that she should have come out of her artistic depression with three novels replete with chatter, small talk and every possible mode of endless conversation and uninterrupted monologues. Could this entanglement of silence and excessive talk be a symptom of her neo-Modernist endeavour (Latham 2016) to articulate the production of subjective responses against contemporary forms of social disconnection?
Objective The objective of this study is to evaluate the frequency and characteristics of facial involvement in inclusion body myositis (IBM) patients and to compare it to the one previously described in facioscapulohumeral dystrophy (FSHD) patients. Methods Thirty-two IBM patients were included and compared to 29 controls and 39 FSHD patients. All participants were recorded in a video as they performed a series of seven facial tasks. Five raters independently assessed facial weakness using both a qualitative evaluation and a semi-quantitative facial weakness score (FWS). Results IBM patients had higher FWS than controls (7.89 ± 7.56 vs 1.06 ± 0.88, p < 0.001). Twenty IBM patients (63%) had a facial weakness with a FWS above the maximum value for controls. All facial tasks were significantly more impaired in IBM patients compared to controls (p < 0.001), task 2 evaluating orbiculari oculi muscle weakness being the most affected. IBM patients with facial weakness reported more swallowing troubles than IBM patients without facial weakness (p = 0.03). FSHD patients displayed higher FWS than IBM patients (12.16 ± 8.37 vs 7.89 ± 7.56, p = 0.01) with more pronounced facial asymmetry (p = 0.01). FWS inter-rater ICC was 0.775. Conclusion This study enabled us to estimate the frequency of facial impairment in IBM in more than half of patients, to detail its characteristics and to compare them with those of FSHD patients. The standardized, semi-quantitative FWS is an interesting diagnostic help in IBM as it appeared more sensitive than qualitative evaluation to detect mild facial weakness.
The objective of this chapter is to reflect on the possibility of a minimal ontology of law, in other words the lowest common denominator between all possible ontologies. The main idea is to reject the conscious or unconscious adherence to a prior theory of law. To this end, it is proposed to analyze the law from the perspective of its practice. It thus appears as a discourse consisting of a set of statements structured by concepts. Without these minimal elements, no practice of law is conceivable. The challenge is to avoid complex and interminable philosophical debates while theorizing the daily practice of law.
This research focuses, in the media public sphere, on the modalities of construction and progressive visibility of persistent symptoms of certain forms of Covid-19, designated by the category “Long Covid”. The aim is to analyze the process according to which this particular form of the disease appeared in the media in June 2020, was the subject of debates and contradictory - even conflicting - positions of the actors, until its institutional and public recognition in 2022. The article conducts a comparative analysis on the French national and regional press and on the digital social network Twitter.
Recently, interest has grown in exploring the hypothesis that neural activity conveys information through precise spiking motifs. To investigate this phenomenon, various algorithms have been proposed to detect such motifs in Single Unit Activity (SUA) recorded from populations of neurons. In this study, we present a novel detection model based on the inversion of a generative model of raster plot synthesis. Using this generative model, we derive an optimal detection procedure that takes the form of logistic regression combined with temporal convolution. A key advantage of this model is its differentiability, which allows us to formulate a supervised learning approach using a gradient descent on the binary cross-entropy loss. To assess the model’s ability to detect spiking motifs in synthetic data, we first perform numerical evaluations. This analysis highlights the advantages of using spiking motifs over traditional firing rate based population codes. We then successfully demonstrate that our learning method can recover synthetically generated spiking motifs, indicating its potential for further applications. In the future, we aim to extend this method to real neurobiological data, where the ground truth is unknown, to explore and detect spiking motifs in a more natural and biologically relevant context.
Foveated vision is a trait shared by many animals, including humans, but its contribution to visual function compared to species lacking it is still under question. This study suggests that the retinotopic mapping which defines foveated vision may play a critical role in achieving efficient visual performance, notably for image categorisation and localisation. To test for this hypothesis, we transformed regular images by using a Log-polar mapping, and used this retinotopic images as the input of convolutional neural networks (CNNs). We then applied transfer learning on pre-trained networks on the ImageNet challenge dataset. Our results show that surprisingly, the network re-trained on images which were compressed by the retinotopic mapping performs as well as the re-trained network applied to regular images. Moreover, we observed that the retinotopic mapping improves the robustness and localisation of image classification, especially for isolated objects. This was specially acute on a custom version of the dataset which aimed to categorise images that contain or not an animal. In summary, these results suggest that such retinotopic mapping may be an important component of preattentive processes, a central cognitive characteristic of more advanced visual systems.
The present study combined behavioral measures and EEG to investigate the impact of emotional valence on both auditory and written word processing. Participants were first presented with a series of auditory words with varying emotional valence (positive, neutral and negative) produced in neutral tone, which they rated according to valence level. Subsequently they performed a surprise recognition task with written stimuli (half being foils). Our results revealed a significant valence/arousal effect on word recognition; written words with high-arousal and either positive or negative valence were recognized with higher accuracy compared to low-arousal neutral ones. EEG analyses revealed an effect of valence only for words presented in written format; no effects were found for auditory words. For written words, both positive and negative valence elicited a larger P2 response in comparison to neutral valence, indicating allocation of attentional resources. Critically, a reduced N400 was observed only for negative words, suggesting facilitated processing of unpleasant information perhaps due to better encoding during the auditory presentation. Overall, our study provides valuable insights into the cognitive mechanisms involved in integrating emotional information presented in distinct modalities, shedding light on the influence of valence on word recognition.
Recent observations from Juno provided a detailed view of Jupiter’s magnetodisk, including its magnetic fields, waves, plasmas and energetic particles. Here, we contribute to Juno results by determining the electric currents threading the magnetodisk and their coupling to field‐aligned currents (FACs) in the midnight‐to‐dawn local time sector. We first derive from Juno magnetic field data the spatial distributions of the height‐integrated radial ( I r ) and azimuthal ( I a ) currents in the magnetodisk, and then calculate the FACs from the divergence of the two current components. The I r ‐associated FAC, J r , flows into and out of the magnetodisk at small and large radial distances, respectively, approximately consistent with the axisymmetric corotation enforcement model. On the other hand, I a decreases with increasing local time everywhere in the local time sector covered, indicating an additional FAC ( J a ) flowing out of the magnetodisk. From I a and J a , we conclude that the influence of the solar wind, which compresses the dayside magnetosphere and thus breaks the axisymmetry of currents and fields, reaches deep to a radial distance of at least about 25 Jupiter radii. Our results provide observational constraints on Jupiter’s magnetosphere‐ionosphere‐thermosphere coupling current systems, on their relation to the main auroral emission and on the radial mass transport rate in the magnetodisk, which we estimate to be close to ∼1500 kg/s. This article is protected by copyright. All rights reserved.
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Nicolas Aubert
  • Centre d'Etudes et de Recherche en Gestion d'Aix-Marseille
Philipp Tsvetkov
  • Centre de Recherches en Oncologie biologique et Onco-pharmacologie (UMR_S 911 CRO2)
58 boulevard Charles Livon, 13284 Marseille Cedex 07, Marseille, France
Head of institution
Eric Berton
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