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The industrial cost of fixed exchange rate regimes
No full textInternational audiencePremature deindustrialization in most emerging and developing economies is one of the most striking stylized facts of the recent decades. In this paper, we provide solid empirical evidence supporting that the choice of a fixed exchange rate regime accelerates this phenomenon. Relying on a panel of 146 developed, emerging, and developing countries over the 1974–2019 period, we show that fixed exchange rate regimes have had a negative, significant, and robust effect on the size of the manufacturing sector—developing countries being the most affected by the industrial cost of such a regime. Additional gravity model regressions show that the impact of fixed regimes passes through the trade channel. In particular, this regime has kept countries with low relative productivity in a state of structural dependence on imports of manufactured products to the detriment of the emergence of a strong local manufacturing sector
TXS 0506+056-like blazar sources and their role as possible neutrino emitters
No full textInternational audienceThe interest in blazars as candidate neutrino emitters grew after the 3 evidence for a contemporaneous joint photon and neutrino emission from the flaring blazar TXS 0506+056 in 2017. Blazars, a class of extragalactic sources with relativistic jets pointing toward Earth, present a broadband emission interpretable via leptonic and hadronic processes, the latter relevant for proton acceleration and neutrino production. Several emission models have been developed to explain this multi-messenger observation, but the details of the neutrino production and the nature of TXS 0506+056 are not yet fully understood. In this work we investigate the properties of sources similar to TXS 0506+056. We select a sample of blazars from the Fermi 4LAC-DR2 catalog by constraining a number of key parameters in ranges centered on TXS 0506+056 values. We estimate their disk accretion efficiency and model their spectral energy distribution (SED) in terms of lepto-hadronic emission, gaining information respectively on the potential similarity of their environment with that of TXS 0506+056 and on their neutrino flux and detectability prospects at TeV energies. Our study shows the candidates’ high energy emission to be dominated by leptonic processes. Part of them also show a high accretion rate, characteristic of FSRQs. For these sources, the very high energy (VHE) and neutrino fluxes appear undetectable by current and future instruments in an average emission state
Des catastrophes, des hommes et des impôts : mécanismes fiscaux et réactions aux 'signes' dans l’Antiquité gréco-romaine
No full textInternational audienc
[Chapter 60] Foamy Viruses
No full textInternational audienceFoamy viruses (FVs) are complex retroviruses. They infect numerous mammalian species, in particular nonhuman primates (NHPs). All simian and prosimian species tested to date harbor exogenous FVs. They exhibit a broad tropism with respect to both cell and host species type. Human beings are not natural hosts for FV, but transmissions from monkeys to man do occur. Like all other retroviruses, FVs establish lifelong persistent infections. According to current knowledge, FVs do not cause any obvious disease, be it within the species of origin or after cross-species transmissions including zoonotic infections of humans. The FV replication cycle deviates from that of the orthoretroviruses, since several hallmarks set them apart from the latter. First, FV mRNA transcription is initiated from an internal promoter (IP), before the viral transactivator initiates expression of the other viral genes transcribed from the LTR-promoter. Second, the pol gene is translated as a separate protein rather than as a Gag-Pol polyprotein, a common characteristic of all other retroviruses. Third, the FV infectious genome consists of DNA rather than RNA with significant amounts of extracellular virions, obtained by in vitro propagation, carrying viral genomic DNA (vgDNA). Finally, with features unique to FVs, their replication includes characteristics from both orthoretroviruses and hepadnaviruses. Consequently, retroviral taxonomy comprises two retroviral subfamilies, the Orthoretrovirinae encompassing the bulk of retrovirus genera, and the Spumaretrovirinae containing five genera.The term “foamy” or latin “spuma” was coined in the 1950s to designate the virus after the observation of a distinct cytopathic effect (CPE) occurring in primary kidney cells derived from monkeys caught in the wild characterized by multinucleated syncytia and vacuolization causing a “foamy” appearance in vitro (Fig. 60.1; Video 60.1). This CPE was attributed to the latent infection of the donor monkeys with a transmittable agent, and eventually, became the light microscopy hallmark of in vitro FV propagation. The first decades of FV research dealt mainly with the identification of infected monkeys, and FVs were regarded as “common contaminants” until they were identified as retroviruses. Molecular cloning of a first FV permitted initial studies on their replication. With respect to their deviations from orthoretroviruses, their ability to cross host species barriers and their potential use as gene transfer systems, FVs are worthy of thorough investigation.This chapter summarizes our knowledge of FV epidemiology, cross-species transmission, virus evolution, and in-depth, their molecular, structural, and cellular biology. Here, we focus on FVs of NHPs and mention the nonprimate viruses if relevant depending to the scientific context. To learn about FV vectors, the reader is referred to specialized reviews.123,126,176,21
Development of molybdenum doped cerium oxide passive counter electrodes by surfactant-assisted ultrasonic spray pyrolysis
No full textInternational audienceNumerous optoelectronic systems, such as electrochromic smart windows, require efficient counter electrodes for their functional operation. Herein, cerium oxide (CeO2) based layers are considered as optically-neutral compounds of high electrochemical activity. Their deposition as thin films onto conducting glass substrates is carried out via surfactant-assisted ultrasonic spray pyrolysis, while further considering heteroelement doping with molybdenum (0–10 %at.). Highly transparent and homogeneous films are accordingly produced, demonstrating important ion storage abilities, especially in the optimal case (6 %at. Mo), bearing a 28 mC cm−2 charging capacity, together with 90+% transmittance over a large optical range. Morpho-structural characterizations additionally highlight a high homogeneity in the deposited layers, owing to the presence of the surfactant species, and enhancing the transmittance of the films. Moreover, the substitution of Ce4+ ions by Mo6+ in the crystal lattice is shown to create additional oxygen vacancies in the layers, contributing to the observed increase in charging capacity. Altogether, excellent optical and electrochemical performances are obtained from such Mo-doped CeO2 formulations, surpassing most of the current related literature. Finally, proof-of-concept electrochromic devices, combining Mo-doped CeO2 optically-neutral electrodes with WO3 films and involving either liquid- or solid, gel-based electrolytes, display great performances of large optical contrasts, fast kinetics, and good coloration efficiencies.</p
Strategies to advance the agroecological transition: Insights from a case study of sheep–crop integration in southwestern France
No full textInternational audienceContext: Mediterranean areas face multiple challenges, including biodiversity loss, soil degradation, and vulnerability to climate change. In southern France's Languedoc region, vineyard monoculture dominates, and livestock systems are rare. Agroecological transitions, especially crop-livestock integration, offer opportunities to diversify systems, recycle nutrients, enhance biodiversity, and reduce fire risks. However, such integration is difficult due to climatic constraints, land accessibility, and the current disconnection between crop and livestock systems.Objective: This study aimed to explore how crop-livestock integration practices in the Minervois territory could be expanded to support agroecological transitions. It focused on identifying synergies that address forage needs for local flocks and create benefits for vineyard and cereal farmers.Methods: As part of a larger participatory and locally grounded approach, we designed agroecological scenarios based on integration of sheep farming system with various crop and semi-natural areas. We assessed the potential to reintroduce livestock in an area where few systems have existed recently. The process identified both the biotechnical and coordination conditions required to sustain livestock with local forage throughout the year and to organize exchanges among stakeholders.Results and conclusions: Except under dry conditions, a flock of 1200 ewes could be sustained year-round through a diversified landscape combining cereal crops, vineyard inter-rows, local rangelands, and transhumance (i.e., moving the flock from one territory to another to graze available forage resources). This diversity enhances agroecological performance through crop-livestock complementarities by exploiting synergies between animal and plant species, over time and space. The method used can be adapted to other territories, and stakeholder involvement is essential for developing understanding and implementing feasible scenariosSignificance: The results support future studies aiming to link forage availability with organizational strategies to identify grazing areas and develop concrete implementation plans
DFT-guided design of melanin-inspired materials for high-performance organic solar cells
No full textInternational audienceOrganic solar cells (OSCs) have rapidly emerged as a promising alternative to traditional photovoltaic technologies, such as crystalline silicon, due to their potential for low-cost, lightweight, and flexible applications. The development of efficient, non-toxic, and earth-abundant materials has motivated the transition from fullerene-based acceptors to non-fullerene counterparts. While current non-fullerene acceptors offer improved spectral absorption, they still present limitations in terms of absorption bandwidth and exciton dissociation efficiency, which constrain overall device performance. In this work, we designed and computationally evaluated a series of donor and acceptor molecules based on Y6 derivatives and melanin-inspired motifs. Specifically, we investigated the effect of incorporating hydroxyindole-based end groups (EGmel) into the Y6 core structure using density functional theory (DFT). Our findings show that the presence of EGmel broadens optical absorption (red-shift of Δλmax up to ≈ 83.61 nm with gap reduction of up to ΔEgap ≈ −0.28 eV) and enhances electron-donating/acceptance capabilities (up to ΔRD ≈ −0.07 and ΔRA ≈ 0.10), key traits for high-performance OSCs. Furthermore, we assessed a set of melanin-like oligomers as potential donor materials, which showed open-circuit voltage predictions comparable to benchmark donors such as PM6 and D18. These findings underscore the potential of bio-inspired modifications, such as hydroxyindole end groups and indolic donor cores, to improve the performance and sustainability of next-generation organic photovoltaic materials
Predicting climate impacts on health at subseasonal-to-seasonal timescales.
No full textInternational audienceThe potential to use subseasonal-to-seasonal (S2S) prediction systems for outcomes in health is presented, using four case studies of malaria, dengue, heat waves, and meningococcal meningitis. While promising, many such applications are currently in the demonstration phase, and examples of operationalizing S2S-based early warning systems, fully integrated with decision support, have yet to emerge. Potential reasons for this operationalization bottleneck are discussed, which include restrictions on open access to health and climate data, the unfulfilled requirement for training in the use of such systems, and the mismatch between the prediction paradigm and the decision entry points in health-planning systems. The S2S project, sponsored by the World Meteorological Organization, may help to demonstrate the potential application of climate information, but the lack of real-time access inhibits the operationalization of evaluated systems. It is recommended that partnership platforms, established through the Global Framework for Climate Services and related mechanisms, enable the climate and health academic and operational communities to work together on real-time provision and assessment of health early warning systems. This is particularly important in developing countries where climate-driven health outcomes can be severe
Performances of conventional and organic livestock development scenarios in France through nitrogen flow analysis
No full textInternational audienceCONTEXTOrganic agriculture (OA) is promoted in the European Union (EU) as a sustainable form of agriculture. However, its expansion may be limited by its dependence on external nitrogen (N) resources, such as conventional manure and imported feed, as it prohibits the use of industrial fertilisers. There is currently no consensus on the role of livestock in scenarios of OA expansion, despite their critical contribution to increasing soil fertility through grazing and nutrient cycling via manure and urine.OBJECTIVEHere, we explored the expansion of OA with a view to having 25 % of total agricultural land under OA by 2030, as defined by the EU Green Deal policy, using two development pathways for organic and conventional livestock: business as usual (BAU) and halving the number of livestock (HL).METHODSWe modelled N flows for organic, conventional and the entire agricultural system using an existing N budget model applied at the national scale for France.RESULTS AND CONCLUSIONSThe results indicated that changing the numbers of livestock species when expanding OA influences N availability. Transitioning to 25 % of agricultural land under OA along with increasing the number of organic livestock in the BAU and HL scenarios decreased total N input, especially industrial fertiliser and feed imports, by 9 % and 28 %, respectively, while decreasing N surpluses by 9 % and 26 %, respectively. In parallel, in the BAU and HL scenarios, biological N fixation increased by 32 % and 61 %, respectively, N output in animal and crop products decreased by 9 % and 30 %, respectively, due to the lower productivity of organic livestock and crops. Notably, this transition implied decreasing human consumption of animal products in the BAU and HL scenarios by 5 % and 30 %, respectively. The scenarios demonstrated the key contribution of livestock and biological N fixation of legumes to the expansion of OA, but further analysis is required, such as considering changes in human diets, farming practices or land use.SIGNIFICANCEThis study highlights simultaneous trade-offs of two agricultural systems at the national scale
Crystallization behavior of co-polyesters based on hydroxy fatty acids extracted from tomato peel agro-wastes
No full textInternational audienceThis work investigates the crystallization behavior of bio-based slightly crosslinked polyester networks synthesized from long-chain hydroxy fatty acids. The crystallization kinetics and the melting behavior were assessed using a combination of modulated-temperature differential scanning calorimetry (MT-DSC) and fast scanning calorimetry (FSC). The characterization of the crystalline phases was performed by X-ray diffraction (XRD) and polarized-light optical (POM) microscopy. A methodology based on calorimetric investigations was used, allowing to estimate the theoretical value of the melting enthalpy of the initial cutin monomers as well as of the derived co-polyester networks. The results obtained by this method allowed to estimate the crystalline content . The combination of XRD and calorimetric analyses evidenced the existence of polymorphs with different stabilities over time at room temperature, characterized by a monotropic transition from the metastable crystal phase (α-phase) to more stable crystal phases (β'and β-phases) depending on the crystallization time accorded to the monomers and the crosslinked co-polyesters. This work delves deeper into the complex crystallization behavior of biobased polyesters, which could eventually allow a better control over the properties of these materials