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Assessing brain state and anesthesia level with two-photon calcium signals
No full textInternational audienceAbstract Brain states, such as wake, sleep, or different depths of anesthesia are usually assessed using electrophysiological techniques, such as the local field potential (LFP) or the electroencephalogram (EEG), which are ideal signals for detecting activity patterns such as asynchronous or oscillatory activities. However, it is technically challenging to have these types of measures during calcium imaging recordings such as two-photon or wide-field techniques. Here, using simultaneous two-photon and LFP measurements, we demonstrate that despite the slower dynamics of the calcium signal, there is a high correlation between the LFP and two-photon signals taken from the neuropil outside neuronal somata. Moreover, we find the calcium signal to be systematically delayed from the LFP signal, and we use a model to show that the delay between the two signals is due to the physical distance between the recording sites. These results suggest that calcium signals alone can be used to detect activity patterns such as slow oscillations and ultimately assess the brain state and level of anesthesia
L'émergence des quartiers culturels et créatifs : l'approche évolutionniste
No full textCahiers ESPI2RLa présente synthèse est issue de l’article “Organic, Planned or Both: Alserkal Avenue, An Art District by Entrepreneurial Action in an Organic Evolutionary Context” publié par Damien D. Nouvel en 2020 dans la revue Built Environment
Stock profiling using time–frequency-varying systematic risk measure
No full textInternational audienceAbstract This study proposes a wavelets approach to estimating time–frequency-varying betas in the capital asset pricing model (CAPM) framework. The dynamic of systematic risk across time and frequency is analyzed to investigate stock risk-profile robustness. Furthermore, we emphasize the effect of an investor’s investment horizon on the robustness of portfolio characteristics. We use a daily panel of French stocks from 2012 to 2022. Results show that varying systematic risk varies in time and frequency, and that its short and long-run evolutions differ. We observe differences in short and long dynamics, indicating that a stock’s betas differently fluctuate to early announcements or signs of events. However, short-run and long-run betas exhibit similar dynamics during persistent shocks. Betas are more volatile during times of crisis, resulting in greater or lesser robustness of risk profiles. Significant differences exist in short-run and long-run risk profiles, implying a different asset allocation. We conclude that the standard CAPM assumes short-run investment. Then, investors should consider time–frequency CAPM to perform systematic risk analysis and portfolio allocation
La Guerre des roses: Rose, mode et féminités dans les années 1950
No full textIn the 1950s, women's fashion was pink, both in the United States and in Europe. This craze followed changes in the conception of femininity, referring to the opposing stereotypes of the "housewife" and the "sex symbol". From Mamie Eisenhower to Marilyn Monroe, the 1950s were the scene of a symbolic 'war' between a conservative pink and a more liberated one.Dans les années 1950, la mode féminine était au rose, aux États-Unis comme en Europe. Cet engouement suivait des changements de la conception de la féminité, renvoyant aux stéréotypes opposés de « la femme au foyer » et de « la sex-symbol » . De Mamie Eisenhower à Marilyn Monroe, les années 1950 furent ainsi le théâtre d’une « guerre » symbolique entre un rose conservateur et un autre plus libéré
L’affranchissement de la femme: de la déconstruction des stéréotypes à la restitution de l’identité de la femme comme sujet
No full textThe status of women, from antiquity to contemporary times, has changed. François Poullain de la Barre on the one hand and Luce Irigaray on the other hand, like other thinkers, with their works, fought against these stereotypes. Thanks to their work, we realize that women are of the same nature as men, but they are different on two levels: identity and aptitudes. The identity of woman which distinguishes her from man is that she is in potency or in mother act. Everything built around the woman does not constitute her identity, her permanent and fundamental character: what makes her individuality, her distinction. It is therefore not a question of reducing woman to submission or motherhood but of recognizing her value and her complementary greatness.Le statut de la femme, de l’Antiquité et à l’époque contemporaine, a connu une mutation. François Poullain de la Barre d’une part et Luce Irigaray d’autre part, comme d’autres penseurs, avec leurs œuvres, ont lutté contre ces stéréotypes. Grâce à leurs travaux, nous nous rendons compte que la femme est de même nature que l’homme mais ils sont différents sur un double plan: identité et aptitudes. L’identité de la femme qui la distingue de l’homme est qu’elle est en puissance ou en acte mère. Tout le construit autour de la femme ne constitue pas son identité, son caractère permanent et fondamental: ce qui fait son individualité, sa distinction. Il n’est donc pas question de réduire la femme à une soumission ou à une maternité mais de reconnaître sa valeur et sa grandeur complémentaire
China and Eurasian Powers in a Multipolar World Order 2.0 Security, Diplomacy, Economy and Cyberspace
No full textInternational audienceThis book argues that the world order is no longer unipolar, and the war in Ukraine proves this fact. As this study describes and theorizes, it has been transformed into a Multipolar World Order 2.0 stage. This title critically examines Chinese, US, Russian, EU, Indian, and a number of other powers’ cooperation and competition over security, diplomatic, economic and cyberspace issues.Accomplished scholars from various regions of the Eurasian continent consider the impact of the Russo–Ukrainian war, the Sino–Russian strategic partnership, China’s relations with the United States and the European Union, the influence of the Belt and Road Initiative, the expansion of the Shanghai Cooperation Organization and Eurasian Economic Union, China’s policies in the Middle East, Central Asia, Indo-Asia Pacific, the South Caucasus, Central and Eastern Europe, as well as focus on details of growing contradictions and collaboration in the Eurasian continent over markets, technologies, digital leadership, vaccine distribution, and financial institutions in the Era of Multipolar World Order 2.0.Showing that the US-centred unipolar world order is replaced by Multipolar World Order 2.0 where conflicting powers fight to keep or extend their spheres of influence, this volume is of great interest to decision makers, diplomats, scholars and students of international relations, politics, global governance, Eurasian studies, Chinese studies, cybersecurity, and economics, and for those studying human security, international organizations, and geopolitics
Co-Design and Experimentation of a Prototype of Agroecological Micro-Farm Meeting the Objectives Set by Climate-Smart Agriculture
No full textInternational audienceDeveloping climate-smart agriculture is an urgent necessity to ensure the food security of a growing global population, to improve the adaptation of agricultural systems to climatic hazards, and to reach a negative carbon balance. Different approaches are being explored to achieve those objectives, including the development of new technologies for efficiency improvements to current systems and substitution of chemical inputs by bio-inputs, but the urgency of the climatic, social, and environmental context calls for more disruptive actions to be taken. We propose an approach to the design of climate-smart production systems structured in four steps: (1) diagnosis of the study region on the basis of the three pillars of climate-smart agriculture, (2) co-design of a disruptive system only based on agroecological and bioeconomic principles, (3) long-term experimentation of this system, and (4) in itinere adjustment of the system based on collected data and on-field evaluations with agricultural stakeholders. The outcome of this approach is the agroecological microfarm named KARUSMART, settled in 2018 on one hectare in the North Basse-Terre region of Guadeloupe (F.W.I.). This study presents its co-design and experimentation stages as well as the first performance results. At the end of the first two years, this microfarm showed a clear improvement in 15 of the 19 indicators used to evaluate the performance of the actual farming systems in the study region. Among the most striking results are a clear superiority in nutritional performance from 3 pers.ha−1 to 8 pers.ha−1 and a reduction in GHG balance from +2.4 tCO2eq.ha−1 to −1.1 tCO2eq.ha−1 for the study area and the microfarm, respectively. These results are promising for developing climate-smart agricultural systems and need to be consolidated further through longer-term monitoring data, the implementation of more similar systems in the study area, and the implementation of the design principles in other contexts
AIDE OU CONTROLE ? : LES CLEFS DU PARADIGME: Vers une évaluation formative par le diagnostic réflexif réciproque du projet professionnel des artistes allocataires du rsa.
No full textVers une évaluation formative par le diagnostic réflexif réciproque du projet professionnel des artistes allocataires du rsa