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Introduction: ‘Other Spaces’ and Dark Places: Reading Heterotopia in Japanese Literature and Culture
No full textInternational audienceThis special issue of the Japan Forum titled ‘“Other spaces” and dark places: reading heterotopia in Japanese literature and culture’ takes inspiration from Michel Foucault’s theory of ‘heterotopia’ to examine sites that,while closely tied to the temporal and spatial network of Japanese contemporary daily life, also stand apart from the everyday. The spaces we examine vary in nature and across time periods: from the geospatial to the metaphorical, the real to the imagined, the Occupation period to fictional futures. The specialissue contains the works of the following scholars: Stephen Dodd, Filippo Cervelli, Thomas Lamarre, Seiji Lippit, Thomas Garcin and Linda Flores. In our explorations of diverse sites such as nightclubs, futuristic societies, university clubs, black markets, convenience stores and narrative space, we demonstrate methods for reading these spaces which are closely intertwined with everyday society but also serve to critique or offer respite from the very society they mirror or represent
Paving the Way to Sociability: Social and Ritual Drinking in Inner Mongolia during the Twentieth and Twenty-First Centuries
No full textInternational audienc
GW231123: A Binary Black Hole Merger with Total Mass 190–265 M
No full textInternational audienceOn 2023 November 23, the two LIGO observatories both detected GW231123, a gravitational-wave signal consistent with the merger of two black holes with masses 137−18+23M⊙and 101−50+22M⊙(90% credible intervals), at a luminosity distance of 0.7–4.1 Gpc, a redshift of 0.40−0.25+0.27, and with a network signal-to-noise ratio of ∼20.7. Both black holes exhibit high spins—0.90−0.19+0.10and 0.80−0.52+0.20, respectively. A massive black hole remnant is supported by an independent ringdown analysis. Some properties of GW231123 are subject to large systematic uncertainties, as indicated by differences in the inferred parameters between signal models. The primary black hole lies within or above the theorized mass gap where black holes between 60–130 M should be rare, due to pair-instability mechanisms, while the secondary spans the gap. The observation of GW231123 therefore suggests the formation of black holes from channels beyond standard stellar collapse and that intermediate-mass black holes of mass ∼200 M form through gravitational-wave-driven mergers
Evolutionary convergences and divergences in sympatric species: Morpho butterflies as a case study
No full textInternational audienceHow do closely related species interact in sympatry? And how do these interactions influence the evolution of their traits and the dynamics of species diversification? In this review, we show how recent research on the evolution of Morpho butterflies contributes to address these questions. We first show how sympatric species have colonized different vertical strata in the neotropical forest and how this divergence has produced cascading adaptive effects on behavioural (flight) but also morphological traits, including wing size, shape and coloration. We then focus on the evolution of peculiar dorsal blue coloration within the genus Morpho . During flight, the blue iridescence produces bright flashes that confuse predators and likely enhance the escape abilities of these butterflies. In turn, predators learn the association between such conspicuous coloration and escaping capacities. Such learning favours the locally abundant colour pattern and promotes the local convergence in sympatric species. However, this tight resemblance also induces sexual interference between mimetic species. Capture–Mark–Recapture data uncovered that mimetic species do not fly at the same hours: competition seems to have driven the divergence in the timing of flight activity between species. Overall, sympatry therefore promotes the intricated evolution of convergent and divergent traits among tightly related species, that jointly facilitate their coexistence. Whether ecological speciation was involved in this evolution is an intriguing open question. At the genomic level, analyses revealed a faster evolution of the sexual chromosome Z as compared to the autosomes, with extensive rearrangements and molecular signals of positive selection: these data thus suggest an important role for the Z chromosome in adaptive evolution in Morpho and possibly in speciation. Paving the way for future research, these various, multilevel studies show that Morpho are not just those showy butterflies in the box: they can also teach us much about evolutionary processes
Steady-state neuron-predominant LINE-1 encoded ORF1p protein and LINE-1 RNA increase with aging in the mouse and human brain
No full textRecent studies have established a reciprocal causal link between aging and the activation of transposable elements, characterized in particular by a de-repression of LINE-1 retrotransposons. These LINE-1 elements represent 21% of the human genome, but only a minority of these sequences retain the coding potential essential for their mobility. LINE-1 encoded proteins can induce cell toxicity implicated in aging and neurodegenerative diseases. However, our knowledge of the expression and localization of LINE-1-encoded proteins in the central nervous system is limited. Using a novel approach combining atlas-based brain mapping with deep-learning algorithms on large-scale pyramidal brain images, we unveil a heterogeneous, neuron-predominant and widespread ORF1p expression throughout the murine brain at steady-state. In aged mice, ORF1p expression increases significantly which is corroborated in human post-mortem dopaminergic neurons by an increase in young LINE-1 elements including those with open reading frames. Mass spectrometry analysis of endogenous mouse ORF1p revealed novel, neuron-specific protein interactors. These findings contribute to a comprehensive description of the dynamics of LINE-1 and ORF1p expression in the brain at steady-state and in aging and provide insights on ORF1p protein interactions in the brain
A Scholar’s Journey to the Afterlife: Case study of Wangjiazui Tomb M798, late 4th century BC, Hubei, China
No full textInternational audienceThe M798 tomb from Wangjiazui cemetery was unearthed in 2021 near the middle reaches of the Yangtze River, which formed the heart of China’s Chu kingdom between the 7th and 3rd centuries BC, and where tens of thousands of burials have been excavated in contemporary times. This tomb, which is dated to the end of the 4th century BC, displays many features typical of Chu kingdom during this period. Above all, it is one of the few antique Chinese tombs to have yielded a batch of inscribed bamboo slips of exceptional volume and content. The textual corpus, which includes 3,200 bamboo slips, consists of long series of sayings attributed to Confucius (551-479 BC), collections of poems, as well as the oldest musical scores unearthed in China. The discovery of such a huge corpus in this grave leads us to consider the deceased’s social class. For this purpose, we will examine the structure of the tomb, the composition and organization of the funerary material, which we will relate to the manuscripts stored in the coffin. We will then determine that the tomb’s occupant was a Chu kingdom scholar. This case study will provide the basis for a more general reflection on the identity and attributes of “scholars” during this period of Chinese antiquity
Efficiency of neural quantum states in light of the quantum geometric tensor
No full textInternational audienceNeural quantum state (NQS) ans\"atze have shown promise in variational Monte Carlo algorithms by their theoretical capability of representing any quantum state. However, the reason behind the practical improvement in their performance with an increase in the number of parameters is not fully understood. In this work, we systematically study the efficiency of restricted Boltzmann Machines (RBMs) to represent the ground states in different phases of the spin-1 bilinear-biquadratic model, as the hidden layer density increases. We train our ansatz by minimizing two different loss functions: 1) energy, and 2) infidelity of the NQS ansatz w.r.t. that of the exact ground state. We observe that the accuracy of our ansatz saturates with in both cases. We demonstrate that this can be explained by looking at the spectrum of the quantum geometric tensor (QGT). We find that the rank of the QGT saturates beyond a certain , and we emphasize that it corresponds to the \textit{dimension of the relevant manifold} for an optimized NQS. This provides a useful diagnostics for the practical representation power of an NQS ansatz
Bounds on detection of Bell correlations with entangled ultra-cold atoms in optical lattices under occupation defects
No full textInternational audienceBell non-locality stems from quantum correlations effectively identified using inequalities. Spin chains, simulated with ultra-cold atoms in optical lattices, Rydberg atoms in tweezer arrays, trapped ions, or molecules, allow single-spin control and measurement. Therefore, they are suitable for studying fundamental aspects of these correlations and non-locality. Occupation defects, such as vacancies or multiple atoms occupying a single site due to imperfect system preparation, limit the detection of Bell correlations. We study their effects with the help of a simplified toy model parameterised by the probability of having a single occupation for a given site. Within this model, and for entangled systems obtained by one-axis twisting evolution from an initial factorised state, we derive two Bell inequalities, one based on many-site correlations and the other on two-site correlations, and identify the smallest probability that allows the Bell inequalities violation to be detected. We then consider two physical realizations using entangled ultra-cold atoms in optical lattices where the parameter is related to a non-unitary filling factor and non-zero temperature. We test the predictions of the toy model against exact numerical results
