Oublier l’auteur au Moyen Age? Réflexions sur l’ars oblivionis des copistes

Cet article développe comment, du XIIe au début du XIVe siècle, les copistes ont fait de leur mode de production un ars oblivionis, mettant à mal la figure de l’auteur; alors qu’en réaction, de la fin du XVe siècle jusqu’au début du XVIe siècle, les auteurs ont mis en œuvre un arsenal de stratégies discursives et littéraires afin d’assurer leur survie. Dès lors, les XIVe et XVe siècles ne seraient plus à envisager comme des siècles de construction de l’auteur médiéval, mais de sa re-naissance, de sa volonté tenace à survivre et à lutter contre sa mise en oubli

Calibration of a Handheld X-Ray Fluorescence Device to Detect Chemical Stabilizers in Soil Subgrades

Chemically stabilized subgrades increase the overall quality of pavements compared to non-treated subgrades. Currently, there is no efficient way to detect chemical stabilizers (CS) in pavement subgrades. Generally, only one test indicating the presence of stabilizers is used, however it is rarely mentioned in the design specifications and can only test the presence of stabilizer, not the concentration. Using X-ray fluorescence (XRF) can provide a quantitative measurement of stabilizer content in soils. Previous research at the University of Oklahoma using a Portable Handheld XRF (PHXRF) device showed the need for a unique calibration for chemical stabilizers in soils. Such a calibration can improve measurements of a PHXRF for determining stabilizer content. To create a new calibration, standard samples were made using different soils, chemical stabilizers, and a range of stabilizer content to create a large number of combinations. The method developed with the PHXRF uses the calcium oxide (CaO) concentration measured in raw soil (without CS), CS, and mixed soil (with CS) to determine the amount of CS in the mixed soil. Additionally, an independent laboratory measured the actual CaO content of each sample using the Whole Rock XRF Analysis, which is a validated technique to detect CS in soils. Samples were also subjected to CaO measurement with the PHXRF device for comparison. Through the calibration process, both values, actual (Whole Rock XRF) and experimental (PHXRF), were used to calculate the correction factor to modify the experimental values to best fit the actual ones. This correction factor was used to develop a new calibration. Two validation procedures were performed to determine the accuracy of the new calibration. First, standard samples were subjected to CaO measurement with the PHXRF device using the new calibration to compare to results of the previous values measured during the calibration. Results closer to the actual values mean that the new calibration improved the device measurement. Other samples not used for the calibration were also prepared and subjected to CaO measurement using the PHXRF device. Two new calibrations were made during this research, one for clay soils and one for sandy soils. The results showed that the PHXRF device provides better CaO content measurements when the coefficients of calibration were applied. The comparison between the new calibrations and the old ones for several samples demonstrated the improvement. The average difference between the SC measurements performed by the device and the actual SC were lower using the new calibrations. However, the new calibration was less accurate than another existing calibration for some high concentration clay samples. Therefore, more studies trying to explain this observation are recommended. Moreover, some additional experiments in the field using the new calibrations are recommended to assess the usability and the accuracy of the new calibrations for quality control purposes. Improving the measurement of SC in soil can significantly improve quality control measures and forensic investigations of pavements leading to increased confidence when stabilizing soils

AdS scale separation and the distance conjecture

It has been argued that orientifold vacua with fluxes in type IIA string theory can achieve moduli stabilisation and arbitrary decoupling between the AdS and KK scales upon sending certain unconstrained RR-flux quanta to infinity. In this paper, we find a novel scalar field in the open-string sector that allows us to interpolate between such IIA vacua that differ in flux quanta and find that the limit of large fluxes is nicely consistent with the distance conjecture. This shows that the massive IIA vacua pass an important Swampland criterion and suggests that scale-separated AdS vacua might not be in the Swampland. Our analysis also naturally suggests a flux analogue of "Reid's fantasy" where flux vacua that differ in quantised flux numbers can be connected through trajectories in open-string field space and not just via singular domain walls.Comment: 19 pages + appendices, 4 figure

Connecting flux vacua through scalar field excursions

We show how flux vacua that differ from each other in flux quanta can be seen as different vacua in a single scalar potential of an enlarged field space, which resolves the separation by thin domain walls. This observation, which is motivated by the AdS Distance Conjecture, allows one to compute distances between different vacua using the usual field space metric. We verify for explicit examples such as scale-seperated IIA flux vacua and the IIB Freund-Rubin vacua that the Distance Conjecture (for scalar fields) is satisfied and that the asymptotic directions in the enlarged field space are indeed hyperbolic. This enlarged field space contains the tachyon fields on the unstable $\tilde{\mathrm{D}}p$-branes of type II string theory, which can induce the brane charges of the stable D-branes. We suggest that requiring continuous interpolations refines the Cobordism Conjecture and postdicts the existence of unstable $\tilde{\mathrm{D}}p$-branes.Comment: 6 pages + appendices, 2 figure

Emergency social protection against the impacts of the pandemic in Latin America and the Caribbean: evidence and lessons learned for universal, comprehensive, sustainable and resilient social protection systems

This paper addresses the emergency non-contributory social protection measures announced in Latin American and Caribbean countries in 2020 and 2021 in response to the coronavirus disease (COVID-19) pandemic. The rapid reaction of the region’s governments and the innovations implemented were key to reaching a large percentage of those affected and containing the adverse effects on poverty and inequality of the measures adopted to contain the pandemic. This process yielded fundamental lessons to advance in the development of mechanisms to provide efficient emergency social protection. The aim is to contribute to discussions on possible ways to strengthen universal, comprehensive, sustainable and resilient social protection systems.Abstract .-- Introduction .-- I. Emergency measures adopted in Latin America and the Caribbean .-- II. Initial results of emergency measures .-- III. Operational challenges and innovations .-- IV. Conclusions and recommendations

Inclusión laboral de las personas jóvenes en América Latina y el Caribe en tiempos de crisis: desafíos de igualdad para las políticas públicas

La juventud es una etapa clave del ciclo de vida, en la que se definen aspectos que marcarán la vida adulta, entre ellos la inclusión en el mercado laboral. Sin embargo, en América Latina y el Caribe, tanto por los problemas estructurales de desigualdad y pobreza como por las consecuencias de la pandemia de enfermedad por coronavirus (COVID-19), la inclusión de las personas jóvenes, y en particular de las mujeres jóvenes, en la educación y el trabajo decente está en riesgo. Frente a esta compleja situación, en este estudio se analizan alternativas de política pública para la mejor inclusión laboral de las personas jóvenes y el desarrollo de sus capacidades y potencialidades. Se analiza, además, el potencial de los programas de inclusión laboral y productiva orientados a la juventud, así como de acciones complementarias como la entrega de transferencias monetarias y la provisión de servicios de cuidado.Resumen .-- Introducción .-- I. Diagnóstico y retos de la inclusión social y laboral de las y los jóvenes .-- II. Programas de inclusión laboral y productiva para las y los jóvenes .-- III. Resultados de evaluaciones de impacto .-- IV. Conclusiones

Protección social de emergencia frente a los impactos de la pandemia de COVID-19 en América Latina y el Caribe: evidencia y aprendizajes sobre sistemas universales, integrales,sostenibles y resilientes de protección social

En el presente documento se abordan las medidas de protección social no contributiva de emergencia anunciadas en los países de América Latina y el Caribe en 2020 y 2021 como respuesta a la pandemia de enfermedad por coronavirus (COVID-19). La rápida reacción de los gobiernos de la región y las innovaciones llevadas a cabo fueron clave para llegar a un amplio porcentaje de la población afectada y contener los efectos adversos en la pobreza y la desigualdad de las medidas tomadas para contener la pandemia. Este proceso permitió extraer lecciones fundamentales para avanzar hacia mecanismos que permitan brindar protección social de emergencia eficiente. Con ello, se espera aportar a la discusión sobre posibles vías para fortalecer sistemas universales, integrales, sostenibles y resilientes de protección social.Resumen .-- Introducción .-- I. Medidas de emergencia adoptadas en América Latina y el Caribe .-- II. Primeros resultados de las medidas de emergencia .-- III. Desafíos e innovaciones operacionales .-- IV. Conclusiones y recomendaciones