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Tax Revenue Mobilization in Developing Countries: Do We Need More Political Veto Players?
No full textInternational audienc
Effect of phoenixin-14 on angiogenesis, cell proliferation, and apoptosis in porcine corpus luteum: Role of GPR173 and ERK1/2, AKT, and AMPK signal pathway
No full textInternational audienceOur previous studies have identified phoenixin-14 (PNX-14) and its receptor GPR173 in the porcine corpus luteum (CL) during the estrous cycle and their role in the endocrine function. This study explored PNX-14's impact on luteal angiogenesis, proliferation, and apoptosis. Luteal cells were cultured with PNX-14 at doses 1-1000 nM for 24-72 h. Then, the transcript level and secretion of angiogenic factors (VEGFA, bFGF2, ANG-1) and protein expression of their receptors (VEGFR1, VEGFR2, FGFR1, FGFR2, TIE2) were analysed. Cell proliferation was assessed using the alamarBlue assay, whereas DNA fragmentation and caspase 3/7 activity through Cell Death Detection ELISA and CaspaseGlo 3/7 assay, respectively. We also examined mRNA and protein levels of proliferating cell nuclear antigen (PCNA), cyclins, and apoptotic factors. Using pharmacological inhibitors of extracellular signal-regulated kinases 1/2 (ERK1/2), protein kinase B (AKT), 5 ' AMP-activated protein kinase (AMPK), and silencing of GPR173 by siRNA we checked their involvement in PNX-14 action in CL. The results showed that PNX-14 increased levels of bFGF2 and ANG-1, and protein expression of VEGFR2, FGFR1, and TIE2, while it decreased FGFR2. It enhanced luteal cell proliferation and PCNA expression, with variable effects on transcript and protein levels of cyclins. Moreover, PNX-14 decreased DNA fragmentation and caspase 3/7 activity, expression of caspases 3, 8, 9, and BAX, and increased BCL2. Additionally, GPR173 receptor and ERK1/2, AKT, and AMPK are involved in PNX-14 action on luteal function. In conclusion, PNX-14 acts as a luteotropic factor in the porcine CL by promoting angiogenesis, proliferation, and protection against apoptosis
Signaux de reconnaissance chimique dans le mutualisme fourmi-puceron : différenciation, partage et modification des composants cuticulaires
No full textFunding for open access publishing: Universidad de Granada/ CBUA. Grant P20_00697 funded by Consejería de Universidad, Investigación e Innovación de la Junta de Andalucía and by “ERDF A way of making Europe”, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (RTA2015-00012-C02-02). The Region Centre Val de Loire funded the TQ-MS (APR-IA 2012)International audienceAphid-tending ants form mutualistic associations with aphids. During their interactions, aphids and ants use both tactile stimuli and chemical cues to communicate. Recent studies suggest that ants modify the cuticular hydrocarbons of mutualistic aphids they attend, but it is unclear which compounds are implicated in recognition. Thus, we investigated the chemical basis for the discrimination between attended and unattended aphids, Aphis gossypii Glover (Hemiptera: Aphididae), by the ant Tapinoma ibericum (Santschi, 1925) including cuticular hydrocarbons (CHCs and non-CHCs) compounds in the analysis. Chemical profiles of 14 colonies of A. gossypii attended by ants for three days were significantly different from those of unattended aphids. These results show that contact with T. ibericum rapidly induces modification of the cuticular profiles of the aphids on which they feed. Moreover, the compounds of unattended aphid A. gossypii also change over time but differ from those of attended aphids. The main compound of the ant cuticle (3,15-di-MeC27), which is highly abundant in attended aphids, was identified as a possible recognition marker, but without forgetting other identified compounds that may also play a predominant role in the ant-aphid mutualistic interactions. These promising compounds represent opportunities for pest control strategies using chemical manipulations
Quelle(s) performativité(s) furent à l'œuvre dans SubLimis ? Les enseignements d'une recherche-création conduite à l'ENSASE
No full textInternational audienceIn 2021, a research-creation project was initiated at ENSASE with several objectives: to contribute to the exploration of the significance of industrial heritage in the Anthropocene; to provide students with an alternative approach to co-producing knowledge, grounded in “what affects them”; to envision, through an exhibition at the 2022 Design Biennale “Bifurcations,” a series of artworks in dialogue with the raw materials of the scenography at the Parc Musée de la Mine Couriot; and to engage in multidisciplinary activities within the ARTS Institute (Jean Monnet University). Thus, the SubLimis project was born.The aim of this contribution is to examine the various agentivities involved in this research-creation process: those related to the research and creation issues; the intentionality behind the act of knowledge production through creative engagement; the materialities and entities present throughout the process, and their interrelations; and finally, the agentivities of research-creation, encompassing not only the research and teaching aspects but also the role of creative work and creation in the face of the current state of the world.En 2021, l'ENSASE a piloté une recherche-création, SubLimis avec pour objectifs principaux de: participer d'une question de recherche autour du sens de l'héritage industriel à l'âge de l'Anthropocène ; proposer aux étudiant.es une autre manière de co-produire de la connaissance en partant de « ce qui les affectent » ; imaginer, par une exposition dans le cadre de la Biennale Design 2022 « Bifurcations », une série d'oeuvres dialoguant avec le matériau premier de la scénographie du Parc Musée de la Mine Couriot ; mener une activité pluridisciplinaire dans le cadre de l'Institut ARTS (Université Jean Monnet). Cette communication souhaite proposer au débat des analyses portant sur les différentes agentivités à l'oeuvre dans SubLimis, qu'elles soient liées aux enjeux de recherche ou de création, à l'intentionnalité de produire de la connaissance par un acte constructif, à la recherche-création elle-même comme apprentissage expérientiel pour les étudiant.es, l'équipe enseignante, les partenaires
Le Poëte et l'Exégète. Présences d'Origène dans l'œuvre de Paul Claudel
No full textInternational audienc
Collective intelligence in work teams: a new multilevel construct and scale
No full textInternational audienceThe conceptualization and assessment of collective intelligence in work teams are currently gray areas in the scholarly psychological literature. The aim of the present research was thus to provide a multilevel conceptualization of collective intelligence in the workplace, and to develop a new assessment scale. After defining this multidimensional construct, we carried out four studies to create and validate an assessment tool. Results support the second-order structure of the scale and confirm its convergent, predictive, divergent and incremental validities at both individual and team levels. Practical implications and avenues for future research are discussed
Global Value Chains in Time of Sanctions
No full textIn recent years, there has been a proliferation of economic sanctions imposed by the United States, the main proponent of such sanctions. Several authors have questioned their effectiveness, as targeted countries may try to evade or circumvent them.Economic sanctions have complex effects, particularly on the global value chain (GVC), which reflects the interdependence of economies. Participation in global value chains can create loopholes that allow sanctioned countries to mitigate their impact. This may be even more the case if sanctions are laxly applied. On the other hand, sanctions may permanently lock countries into low-value-added activities. This study examines the complex effects of US economic sanctions on the participation of targeted countries in global value chains. Using a panel of 102 developing countries from 1990 to 2018 and applying the entropy balancing method, it finds that US economic sanctions reduce participation in global value chains by 1.06 percentage points relative to non-targeted countries. Results show that trade and financial sanctions hinder global value chain participation, with a sanctioned country losing almost 5 years of progress in the GVC. The effects are more pronounced for highly trade-dependent and resource-rich economies, while countries with strong financial systems are more resilient. This impact is supported by an alternative method involving the use of an instrumental variable estimator.Relying on other alternative econometric methods does not change the main results.Lower foreign direct investment (FDI), reduced innovation capacity, exclusion from international financial networks and increased macroeconomic uncertainty, as measured by inflation and real effective exchange rate volatility, are the main drivers of the impact of economic sanctions on participation in global value chains.</p
Invalidité et indemnisation des pertes de gains professionnels futurs : quelle articulation ?
No full textInternational audienceObservations sur Civ. 2, 3 avril 2025, n° 23-19.227L'impossibilité de retrouver un emploi ne peut se déduire du seul classement en invalidité de 2e catégorie par la caisse de sécurité sociale, lequel ne suffit donc pas à justifier l'indemnisation d'une perte totale des gains professionnels futurs
Mechanical loading dependence on burning surface areas
No full textInternational audienceThe transition from normal (surface) to abnormal (convective) burning modes of explosives is still a difficult phenomenon to model. This transition, which yields the acceleration of the combustion propagation, could result in a violent reaction. Nowadays, abnormal burning is interpreted as an increase in burning surface area. The latter depends on the initial state of the microstructure and therefore of the mechanical history. This paper considers the coupling between the combustion of HMX-based polymerbonded explosives and its previous mechanical loadings. The experimental set-ups used to (1) apply a triaxial compression (that mimics the mechanical fields experienced by the explosive composition when submitted to a Steven test) and ( 2) burn the samples in a closed vessel will be described. Experiments show a strong dependence on the critical pressure leading to abnormal combustion on a previous mechanical loading. An analytical model is proposed to determine the real-time burning surface area during combustion. It enables modelling of the increase in surface area increase when the critical pressure is reached. Experimental results and surface determinations are presented in this paper. Future works will be discussed