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Doubling down: The synergy of CCyB release and monetary policy easing
No full textInternational audienceAt the height of the COVID-19 crisis, many countries have reduced their countercyclical capital buffer (CCyB) and cut key policy rates. We exploit this quasi-natural experiment to gauge the combined effects of these two policies on bank lending rates (BLRs). First, we theoretically show that the joint action of CCyB release and monetary policy easing lowers BLRs by more than the sum of their individual effects. We then empirically confirm this synergy by a difference-in-difference analysis. Notably, for one percentage point release of the CCyB, corporate BLRs decreased by around 11 basis points more compared to countries without CCyB relief. The lower the policy rate, the greater this effect, suggesting that the CCyB provided additional room for maneuver to monetary policy. In addition, releasing the CCyB has acted as a catalyst for a better transmission of policy rate cuts
Engaging scientists around controversial research: studying cognitive neuroscience in non-human primates and participating in science communication activities
No full textInternational audienceOver the last 15 years, research involving animals has evolved considerably in Europe, mainly because of increasingly strict regulations and major technological developments. At the same time, the perception of animals has also shifted towards increased attention to animal welfare. Undoubtedly, this double evolution has consequences for the scientific communication of such topics. While the public engagement of scientists is increasingly expected, the situation might differ for sensitive topics, such as non-human primate research. As this population has little public profile and is often reluctant to speak out, we do not know much about their attitudes toward public engagement, willingness to participate, or perception of the public.Through semi-structured interviews (n = 11) with scientists working in cognitive neurosciences with non-human primates, we highlight the role of institutions in researchers' engagement and the dichotomy between the perception of the public and its expectations and communication objectives, which we link to the controversial dimension of this research field.We suggest that a change in institutional strategy, both in public relations and towards researchers, could be useful in advancing communication about research on non-human primates. The communication practices of the respondents indicated that certain formats allow for more peaceful and fruitful exchanges with the public, particularly small-group events, from which institutional communication bodies can draw inspiration. This highlights the importance of a scientific communication model based on dialogue in this type of sensitive context. Finally, the communication objectives expressed by researchers emphasise the ongoing challenging situation of animal experimentation, particularly with primates, in public opinion, and the perceived and sometimes endured necessity to position themselves as defenders of the practice
Analyse du vieillissement cognitif dans l’autisme à travers les performances et le ressenti des difficultés.
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Invariant response to faces in ASD: Unexpected trajectory of oculo-pupillometric biomarkers from childhood to adulthood
No full textInternational audienceHuman faces contain a large amount of information, capturing our attention and inducing physiological engagement. Oculometric (visual exploration) and pupillometric (physiological reactivity) parameters quantified by eye-tracking are potent tools for exploring attraction to human faces from an early age. Autistic people have particularities in visual exploration and physiological reactivity to faces, with reduced time spent on the eyes associated with reduced pupil dilation. To date, no study has assessed the age differences of oculo-pupillometric parameters in response to faces. This study aimed to characterize these parameters in neurotypical (n = 150) and autistic (n = 109) populations (3-34 years old). Visual stimuli were organized along a social saliency gradient, from objects to faces. Oculo-pupillometric responses to faces appear invariant across age in the autistic population, contrary to the neurotypical population that shows an increasing attentional focus on the eye region with age, and a larger pupillary sensitivity to social salient stimuli at an early age. Our results highlight an apparent lack of maturation of face processing in autism spectrum disorder (ASD) at the population level, possibly hiding atypical and complex individual trajectories. However, these findings also point to age windows in which specific parameters could be used as discriminating biomarkers of ASD
Construction narrative et réflexion politique chez Hérodote : les deux tableaux d'Athènes et de Sparte dans l'Enquête (1, 59-68 ; 5, 39-48 et 55-97)
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Inhibition of p38α MAPK increases short-term astrocyte reactivity: the exploratory VIP trial in early Alzheimer’s disease
No full textInternational audienceBackgroundNeuro-inflammation is an early mechanistic target in Alzheimer’s disease (AD). However, the effect of anti-inflammatory drugs on biomarkers of neuro-inflammation has yet to be described. Biomarkers of neuro-inflammation showed distinct evolution over the course of AD, suggesting that anti-inflammatory interventions could be beneficial or interfere with mechanisms of immune defense.MethodsWe conducted a pilot and exploratory phase II trial to evaluate the short-term effects of neflamapimod, a drug known to inhibit the neuro-toxic pro-inflammatory properties of the p38α MAPK. Participants with early AD were randomized to receive neflamapimod 40 mg (n = 17) or placebo (n = 16) twice-daily for 12 weeks. The primary endpoint was the treatment-related change in PET imaging of the translocator protein (TSPO) using [18F]-DPA-714. The main secondary endpoints were cerebrospinal fluid (CSF) markers of microglial and astrocyte reactivity. We hypothesized that neuro-inflammation would be reduced at three months in PET and in CSF markers.ResultsNeuro-inflammation was not reduced between the neflamapimod and placebo groups, and no change was observed in [18F]-DPA-714 PET. However, neflamapimod induced a significant increase in CSF GFAP levels compared to placebo. Multivariate analyses based on CSF biomarkers highlighted the contribution of sTREM2 in the pattern of variation that discriminated the two groups (accuracy = 71%). Patients who received neflamapimod and had baseline sTREM2 level above the median had the highest increase in GFAP compared to placebo, suggesting that neflamapimod may exacerbate reactive astrogliosis as a function of the TREM2-related microglial state. Safety analysis showed that three cases of CSF pleocytosis occurred during follow-up in participants receiving neflamapimod.ConclusionsNeflamapimod at a dose of 40 mg twice-daily interfered with mechanisms of immune defense in early AD. Although this study is exploratory, our results may provide an explanation for the failure of previous anti-inflammatory interventions in early AD. Biomarkers of neuro-inflammation should be required in the next-generation trials targeting neuro-immune mechanisms in AD
Bifurcation analysis of a size-structured population model: Application to oocyte dynamics and ovarian cycle
No full textMerci de faire évoluer le preprint en article après publicationInternational audienceWe introduce and analyze a quasilinear size-structured population model with non-linearities accounting for nonlocal interactions between individuals. The recruitment (immigration), growth and death rates are inhomogeneous in time and/or space and depend on weighted averages of the density. We first prove the existence and uniqueness of globally bounded weak solutions using the characteristic curves and Banach fixed point Theorem, after transforming the partial differential equation into an equivalent system of integral equations. We then investigate the long-time behavior of the PDE in the case when the growth rate is separable. Applying a classical time-scaling transformation, the problem boils down to a PDE with linear growth rate and nonlinear inflow boundary condition, entering the theoretical framework of abstract semilinear Cauchy problems. We can then perform a bifurcation analysis which reveals the richness of the model behavior. Depending on the ratio of the recruitment to the growth rate, the model can exhibit multistability and stable oscillatory solutions, emanating respectively through saddle-node and Hopf bifurcations. We illustrate these theoretical results on the biological application motivating this work, oogenesis, the process of production and maturation of female gametes (oocytes) that is critical to reproductive fitness
A reflection on “Intriguing aspects of lanthanide luminescence”
No full textInternational audienceLanthanide luminescence surrounds us in everyday life and is essential for cutting-edge technological and healthcare applications. In 2013, we published a minireview in Chemical Science (Chem. Sci., 2013, 4, 1939–1949, https://doi.org/10.1039/C3SC22126A) that was focused on the latest innovations and less-known aspects of lanthanide luminescence in applications such as biological imaging, sensing and therapy, security inks and anti-counterfeiting tags, luminescent probes and sensors, and solar energy conversion. Herein, a discussion of the progress of this field is provided with support of the most recent examples in the areas of circularly polarized luminescence, nanothermometry and multiplexed biological imaging in the extended second near-infrared window (NIR-II, 1000–3000 nm)
Carbon curse: As you extract, so you will burn
No full textInternational audienceThe “Carbon Curse” theory suggests that fossil fuel wealth leads countries to have more carbon intensive development trajectories than they would otherwise. Using causal inference for cross-country panel data spanning 1950–2018, we globally estimate the effect of giant oil and gas discoveries on carbon emissions. Our results show a substantial and persistent impact: Countries that experience giant oil and gas discoveries emit approximately 50% more post-discovery CO2 per unit of GDP and per capita compared to their resource-poor counterparts. The effect is even higher in developing economies, with an increase of around 65%, compared to about 33% in developed countries. These findings highlight the significant barriers that fossil fuel-rich nations face in aligning with decarbonization goals, posing substantial challenges for meeting the Paris Agreement targets. By exploiting the randomness of the timing of discoveries, we provide the first plausibly-causal evidence in support of the”Carbon Curse”
Missense mutation in the activation segment of the kinase CK2 models Okur-Chung neurodevelopmental disorder and alters the hippocampal glutamatergic synapse
No full textInternational audienceExome sequencing has enabled the identification of causative genes of monogenic forms of autism, amongst them, in 2016, CSNK2A1, the gene encoding the catalytic subunit of the kinase CK2, linking this kinase to Okur-Chung Neurodevelopmental Syndrome (OCNDS), a newly described neurodevelopmental condition with many symptoms resembling those of autism spectrum disorder. Thus far, no preclinical model of this condition exists. Here we describe a knock-in mouse model that harbors the K198R mutation in the activation segment of the α subunit of CK2. This region is a mutational hotspot, representing one-third of patients. These mice exhibit behavioral phenotypes that mirror patient symptoms. Homozygous knock-in mice die mid-gestation while heterozygous knock-in mice are born at half of the expected mendelian ratio and are smaller in weight and size than wildtype littermates. Heterozygous knock-in mice showed alterations in cognition and memory-assessing paradigms, enhanced stereotypies, altered circadian activity patterns, and nesting behavior. Phosphoproteome analysis from brain tissue revealed alterations in the phosphorylation status of major pre- and postsynaptic proteins of heterozygous knock-in mice. In congruence, we detect reduced synaptic maturation in hippocampal neurons and attenuated long-term potentiation in the hippocampus of knock-in mice. Taken together, heterozygous knock-in mice (CK2αK198R/+) exhibit significant face validity, presenting ASD-relevant phenotypes, synaptic deficits, and alterations in synaptic plasticity, all of which strongly validate this line as a mouse model of OCNDS