Université Paris 1 Panthéon-Sorbonne

Disorders of the brain can exhibit considerable epidemiological comorbidity and often share symptoms, provoking debate about their etiologic overlap. We quantified the genetic sharing of 25 brain disorders from genome-wide association studies of 265,218 patients and 784,643 control participants and assessed their relationship to 17 phenotypes from 1,191,588 individuals. Psychiatric disorders share common variant risk, whereas neurological disorders appear more distinct from one another and from the psychiatric disorders. We also identified significant sharing between disorders and a number of brain phenotypes, including cognitive measures. Further, we conducted simulations to explore how statistical power, diagnostic misclassification, and phenotypic heterogeneity affect genetic correlations. These results highlight the importance of common genetic variation as a risk factor for brain disorders and the value of heritability-based methods in understanding their etiology.

COVID-19 is a systemic infection with a significant impact on the hematopoietic system and hemostasis. Lymphopenia may be considered as a cardinal laboratory finding, with prognostic potential. Neutrophil/lymphocyte ratio and peak platelet/lymphocyte ratio may also have prognostic value in determining severe cases. During the disease course, longitudinal evaluation of lymphocyte count dynamics and inflammatory indices, including LDH, CRP and IL-6 may help to identify cases with dismal prognosis and prompt intervention in order to improve outcomes. Biomarkers, such high serum procalcitonin and ferritin have also emerged as poor prognostic factors. Furthermore, blood hypercoagulability is common among hospitalized COVID-19 patients. Elevated D-Dimer levels are consistently reported, whereas their gradual increase during disease course is particularly associated with disease worsening. Other coagulation abnormalities such as PT and aPTT prolongation, fibrin degradation products increase, with severe thrombocytopenia lead to life-threatening disseminated intravascular coagulation (DIC), which necessitates continuous vigilance and prompt intervention. So, COVID-19 infected patients, whether hospitalized or ambulatory, are at high risk for venous thromboembolism, and an early and prolonged pharmacological thromboprophylaxis with low molecular weight heparin is highly recommended. Last but not least, the need for assuring blood donations during the pandemic is also highlighted.

The socio-economic impacts on cities during the COVID-19 pandemic have been brutal, leading to increasing inequalities and record numbers of unemployment around the world. While cities endure lockdowns in order to ensure decent levels of health, the challenges linked to the unfolding of the pandemic have led to the need for a radical re-think of the city, leading to the re-emergence of a concept, initially proposed in 2016 by Carlos Moreno: the “15-Minute City”. The concept, offering a novel perspective of “chrono-urbanism”, adds to existing thematic of Smart Cities and the rhetoric of building more humane urban fabrics, outlined by Christopher Alexander, and that of building safer, more resilient, sustainable and inclusive cities, as depicted in the Sustainable Development Goal 11 of the United Nations. With the concept gaining ground in popular media and its subsequent adoption at policy level in a number of cities of varying scale and geographies, the present paper sets forth to introduce the concept, its origins, intent and future directions.

Aggregation is the process of combining several numerical values into a single representative value, and an aggregation function performs this operation. These functions arise wherever aggregating information is important: applied and pure mathematics (probability, statistics, decision theory, functional equations), operations research, computer science, and many applied fields (economics and finance, pattern recognition and image processing, data fusion, etc.). This is a comprehensive, rigorous and self-contained exposition of aggregation functions. Classes of aggregation functions covered include triangular norms and conorms, copulas, means and averages, and those based on nonadditive integrals. The properties of each method, as well as their interpretation and analysis, are studied in depth, together with construction methods and practical identification methods. Special attention is given to the nature of scales on which values to be aggregated are defined (ordinal, interval, ratio, bipolar). It is an ideal introduction for graduate students and a unique resource for researchers.

This paper investigates the distribution of well being among world citizens during the last two centuries. The estimates show that inequality of world distribution of income worsened from the beginning of the 19th century to World War II and after that seems to have stabilized or to have grown more slowly. In the early 19th century most inequality was due to differences within countries; later, it was due to differences between countries. Inequality in longevity, also increased during the 19th century, but then was reversed in the second half of the 20th century, perhaps mitigating the failure of income inequality to improve in the last decades.

This paper studies the links between productivity, innovation and research at the firm level. We introduce three new features: (i) A structural model that explains productivity by innovation output, and innovation output by research investment: (ii) New data on French manufacturing firms, including the number of European patents and the percentage share of innovative sales, as well as firm-level demand pull and technology push indicators; (iii) Econometric methods which correct for selectivity and simultaneity biases and take into account the statistical features of the available data: only a small proportion of firms engage in research activities and/or apply for patents; productivity, innovation and research are endogenously determined; research investment and capital are truncated variables, patents are count data and innovative sales are interval data. We find that using the more widespread methods, and the more usual data and model specification, may lead to sensibly different estimates. We find in particular that simultaneity tends to interact with selectivity, and that both sources of biases must be taken into account together. However our main results are consistent with many of the stylized facts of the empirical literature. The probability of engaging in research (R&D) for a firm increases with its size (number of employees), its market share and diversification, and with the demand pull and technology push indicators. The research effort (R&D capital intensity) of a firm engaged in research increases with the same variables, except for size (its research capital being strictly proportional to size). The firm innovation output, as measured by patent numbers or innovative sales, rises with its research effort and with the demand pull and technology indicators, either directly or indirectly through their effects on research. Finally, firm productivity correlates positively with a higher innovation output, even when controlling for the skill composition of labor as well as for physical capital intensity.

In this paper, we contribute to the literature on the determinants of foreign direct investment in developing countries and re‐evaluate the role of the quality of institutions on FDI independently of the general level of development. We implement cross‐section estimations based on a newly available database with unprecedented detail on institutions for a set of 52 countries, as well as panel data estimations based on Fraser Institute's data. Furthermore, we control for the correlation between institutions and GDP per capita and for endogeneity of institutions. Finally, we evaluate whether the similarity of institutions between the host and the origin country raises bilateral FDI. We find that a wide range of institutions, including bureaucracy, corruption, but also information, banking sector and legal institutions, do matter for inward FDI independently of GDP per capita. Interestingly, weak capital concentration and strong employment protection tend to reduce inward FDI. Institutional proximity between the origin and the host country also matters, but we find little impact of institutions in the origin country. These results are encouraging in the sense that efforts towards raising the quality of institutions and making them converge towards those of source countries may help developing countries to receive more FDI, independently of the indirect impact of higher GDP per capita. The orders of magnitude found in the paper are large, meaning that moving from a low level to a high level of institutional quality could have as much impact as suddenly becoming a neighbour of a source country.

Research on the spatial aspects of economic activity has flourished over the past decade due to the emergence of new theory, new data, and an intense interest on the part of policymakers, especially in Europe but increasingly in North America and elsewhere as well. However, these efforts--collectively known as the "new economic geography"--have devoted little attention to the policy implications of the new theory. Economic Geography and Public Policy fills the gap by illustrating many new policy insights economic geography models can offer to the realm of theoretical policy analysis. Focusing primarily on trade policy, tax policy, and regional policy, Richard Baldwin and coauthors show how these models can be used to make sense of real-world situations. The book not only provides much fresh analysis but also synthesizes insights from the existing literature. The authors begin by presenting and analyzing the widest range of new economic geography models to date. From there they proceed to examine previously unaddressed welfare and policy issues including, in separate sections, trade policy (unilateral, reciprocal, and preferential), tax policy (agglomeration with taxes and public goods, tax competition and agglomeration), and regional policy (infrastructure policies and the political economy of regional subsidies). A well-organized, engaging narrative that progresses smoothly from fundamentals to more complex material, Economic Geography and Public Policy is essential reading for graduate students, researchers, and policymakers seeking new approaches to spatial policy issues.

During the last decennia media environments and political communication systems have changed fundamentally. These changes have major ramifications for the political information environments and the extent to which they aid people in becoming informed citizens. Against this background, the purpose of this article is to review research on key changes and trends in political information environments and assess their democratic implications. We will focus on advanced postindustrial democracies and six concerns that are all closely linked to the dissemination and acquisition of political knowledge: (1) declining supply of political information, (2) declining quality of news, (3) increasing media concentration and declining diversity of news, (4) increasing fragmentation and polarization, (5) increasing relativism and (6) increasing inequality in political knowledge.

Abstract This article aims at defining the concept of “semi-presidential government” and detailing the diversity of its practices. There are in fact three types of semi-presidential regimes: the president can be a mere figurehead, or he may be all-powerful or again he can share his power with parliament. Using four parameters — the content of the constitution, tradition and circumstances, the composition of the parliamentary majority and the position of the president in relation to the majority — the author seeks to explain why similar constitutions are applied in a radically different manner.

We combine high-redshift Type Ia supernovae from the first three years of the Supernova Legacy Survey (SNLS) with other supernova (SN) samples, primarily at lower redshifts, to form a high-quality joint sample of 472 SNe (123 low-z, 93 SDSS, 242 SNLS, and 14 Hubble Space Telescope). SN data alone require cosmic acceleration at >99.999% confidence, including systematic effects. For the dark energy equation of state parameter (assumed constant out to at least z = 1.4) in a flat universe, we find w = –0.91^(+0.16)_(–0.20)(stat)^(+0.07)_(–0.14)(sys) from SNe only, consistent with a cosmological constant. Our fits include a correction for the recently discovered relationship between host-galaxy mass and SN absolute brightness. We pay particular attention to systematic uncertainties, characterizing them using a systematic covariance matrix that incorporates the redshift dependence of these effects, as well as the shape-luminosity and color-luminosity relationships. Unlike previous work, we include the effects of systematic terms on the empirical light-curve models. The total systematic uncertainty is dominated by calibration terms. We describe how the systematic uncertainties can be reduced with soon to be available improved nearby and intermediate-redshift samples, particularly those calibrated onto USNO/SDSS-like systems.

Abstract Urban shrinkage is not a new phenomenon. It has been documented in a large literature analyzing the social and economic issues that have led to population flight, resulting, in the worse cases, in the eventual abandonment of blocks of housing and neighbourhoods. Analysis of urban shrinkage should take into account the new realization that this phenomenon is now global and multidimensional — but also little understood in all its manifestations. Thus, as the world's population increasingly becomes urban, orthodox views of urban decline need redefinition. The symposium includes articles from 10 urban analysts working on 30 cities around the globe. These analysts belong to the Shrinking Cities International Research Network (SCIRN), whose collaborative work aims to understand different types of city shrinkage and the role that different approaches, policies and strategies have played in the regeneration of these cities. In this way the symposium will inform both a rich diversity of analytical perspectives and country‐based studies of the challenges faced by shrinking cities. It will also disseminate SCIRN's research results from the last 3 years. Résumé La décroissance urbaine n'est pas un phénomène nouveau. De nombreux travaux ont analysé les problèmes sociaux et économiques conduisant au départ de populations et résultant dans les pires des cas à l'abandon d'îlots d'habitat et de quartiers entiers. Cependant, l'étude de la décroissance urbaine doit aujourd'hui tenir compte du constat récent selon lequel ce phénomène est désormais global et multidimensionnel, tout en restant peu appréhendé dans toutes ses composantes. Ainsi, alors que la population mondiale est de plus en plus urbaine, les conceptions classiques du déclin urbain méritent d'être réexaminées. Ce symposium inclut des articles de dix chercheurs travaillant sur trente villes à travers le monde. Ils appartiennent au Shrinking Cities International Research Netwok (SCIRN), dont le travail collectif a pour objectif d'analyser différents types de décroissance urbaine et le rôle que les multiples approches, politiques et stratégies ont joué dans la régénération des villes touchées par ce processus. Ce numéro s'appuie sur une diversité d'approches et sur l'étude de contextes urbains variés, ayant pour point commun d'être concernés par les enjeux de la décroissance urbaine. Il permet de diffuser les résultats des recherches menées au sein du SCIRN au cours des trois dernières années.

Louis Martin, Benjamin Muller, Pedro Javier Ortiz Suárez, Yoann Dupont, Laurent Romary, Éric de la Clergerie, Djamé Seddah, Benoît Sagot. Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics. 2020.

This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961–2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO2) and sulfur dioxide (SO2) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO2 emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO2 emissions. Furthermore, the causality results show that the relationship between income and pollution in Tunisia is one of unidirectional causality with income causing environmental changes and not vice versa, both in the short-run and long-run. This implies that an emission reduction policies and more investment in pollution abatement expense will not hurt economic growth. It could be a feasible policy tool for Tunisia to achieve its sustainable growth in the long-run.

Abstract. The aim of this paper is to provide the community with a comprehensive overview of the studies of glaciers in the tropical Andes conducted in recent decades leading to the current status of the glaciers in the context of climate change. In terms of changes in surface area and length, we show that the glacier retreat in the tropical Andes over the last three decades is unprecedented since the maximum extension of the Little Ice Age (LIA, mid-17th–early 18th century). In terms of changes in mass balance, although there have been some sporadic gains on several glaciers, we show that the trend has been quite negative over the past 50 yr, with a mean mass balance deficit for glaciers in the tropical Andes that is slightly more negative than the one computed on a global scale. A break point in the trend appeared in the late 1970s with mean annual mass balance per year decreasing from −0.2 m w.e. in the period 1964–1975 to −0.76 m w.e. in the period 1976–2010. In addition, even if glaciers are currently retreating everywhere in the tropical Andes, it should be noted that this is much more pronounced on small glaciers at low altitudes that do not have a permanent accumulation zone, and which could disappear in the coming years/decades. Monthly mass balance measurements performed in Bolivia, Ecuador and Colombia show that variability of the surface temperature of the Pacific Ocean is the main factor governing variability of the mass balance at the decadal timescale. Precipitation did not display a significant trend in the tropical Andes in the 20th century, and consequently cannot explain the glacier recession. On the other hand, temperature increased at a significant rate of 0.10 °C decade−1 in the last 70 yr. The higher frequency of El Niño events and changes in its spatial and temporal occurrence since the late 1970s together with a warming troposphere over the tropical Andes may thus explain much of the recent dramatic shrinkage of glaciers in this part of the world.

Abstract. Results from the fully and biogeochemically coupled simulations in which CO2 increases at a rate of 1 % yr−1 (1pctCO2) from its preindustrial value are analyzed to quantify the magnitude of carbon–concentration and carbon–climate feedback parameters which measure the response of ocean and terrestrial carbon pools to changes in atmospheric CO2 concentration and the resulting change in global climate, respectively. The results are based on 11 comprehensive Earth system models from the most recent (sixth) Coupled Model Intercomparison Project (CMIP6) and compared with eight models from the fifth CMIP (CMIP5). The strength of the carbon–concentration feedback is of comparable magnitudes over land (mean ± standard deviation = 0.97 ± 0.40 PgC ppm−1) and ocean (0.79 ± 0.07 PgC ppm−1), while the carbon–climate feedback over land (−45.1 ± 50.6 PgC ∘C−1) is about 3 times larger than over ocean (−17.2 ± 5.0 PgC ∘C−1). The strength of both feedbacks is an order of magnitude more uncertain over land than over ocean as has been seen in existing studies. These values and their spread from 11 CMIP6 models have not changed significantly compared to CMIP5 models. The absolute values of feedback parameters are lower for land with models that include a representation of nitrogen cycle. The transient climate response to cumulative emissions (TCRE) from the 11 CMIP6 models considered here is 1.77 ± 0.37 ∘C EgC−1 and is similar to that found in CMIP5 models (1.63 ± 0.48 ∘C EgC−1) but with somewhat reduced model spread. The expressions for feedback parameters based on the fully and biogeochemically coupled configurations of the 1pctCO2 simulation are simplified when the small temperature change in the biogeochemically coupled simulation is ignored. Decomposition of the terms of these simplified expressions for the feedback parameters is used to gain insight into the reasons for differing responses among ocean and land carbon cycle models.

Data infrastructures, economic processes, and governance models of digital platforms are increasingly pervading urban sectors and spheres of urban life. This phenomenon is known as platformization, which has in turn given rise to the phenomena of platform society, where platforms have permeated the core of urban societies. A recent manifestation of platformization is the Metaverse, a global platform project launched by Meta (formerly Facebook) as a globally operating platform company. The Metaverse represents an idea of a hypothetical “parallel virtual world” that incarnate ways of living and working in virtual cities as an alternative to smart cities of the future. Indeed, with emerging innovative technologies—such as Artificial Intelligence, Big Data, the IoT, and Digital Twins—providing rich datasets and advanced computational understandings of human behavior, the Metaverse has the potential to redefine city designing activities and service provisioning towards increasing urban efficiencies, accountabilities, and quality performance. However, there still remain ethical, human, social, and cultural concerns as to the Metaverse’s influence upon the quality of human social interactions and its prospective scope in reconstructing the quality of urban life. This paper undertakes an upper-level literature review of the area of the Metaverse from a broader perspective. Further, it maps the emerging products and services of the Metaverse, and explores their potential contributions to smart cities with respect to their virtual incarnation, with a particular focus on the environmental, economic, and social goals of sustainability. This study may help urban policy makers to better understand the opportunities and implications of the Metaverse upon tech-mediated practices and applied urban agendas, as well as assess the positives and negatives of this techno-urban vision. This paper also offers thoughts regarding the argument that the Metaverse has disruptive and substantive effects on forms of reconstructing reality in an increasingly platformized urban society. This will hopefully stimulate prospective research and further critical perspectives on the topic.

Abstract I provide an overall empirical assessment of the motivations of ODA granted by rich countries to developing countries, as revealed by aid allocation behaviors. Aid motives combine self‐interested and altruistic objectives. I use a three‐dimensional panel dataset, combining the donor, recipient and time dimensions, which shows a lot of heterogeneity in donor behavior. Thanks to the width of this dataset, I can test differences of parameters among donors and, in particular, compare their degrees of altruism. Switzerland, Austria, Ireland and most Nordic countries are among the most altruistic. Australia, France, Italy, and to some extent Japan and the United States are among the most egoistic.

Sustainable tourism indicators (STIs) are an integral element of tourism planning and management. This study systematically reviews the research contributions on the development of STIs based on four criteria including: i) the relevance of the STIs to the sustainable development goals (SDGs); ii) governance; iii) stakeholders involved; and iv) the distinction between subjective and objective indicators. A search of Scopus indexed journals published up to April 2018, yielded 97 papers for examination. The findings demonstrate the lack of direct attention to the SDGs in those papers published after their launch in 2016. However, the majority of the SDGs and their targets have indirectly been covered in the reviewed papers. The results revealed that, among the sustainability themes of economic growth, social inclusion, environmental protection, and governance, the STIs studies tended to overlook the dimension of governance. The findings showed that residents are the most engaged stakeholder group, and tourists the least engaged as compared with government and businesses. The results also indicated that more attention is afforded to objective compared to subjective indicators. The findings also demonstrated that much of the focus is on European countries rather than the Global South which is the major focus of the SDGs.

The concept of feedback is key in assessing whether a perturbation to a system is amplified or damped by mechanisms internal to the system. In polar regions, climate dynamics are controlled by both radiative and non-radiative interactions between the atmosphere, ocean, sea ice, ice sheets and land surfaces. Precisely quantifying polar feedbacks is required for a process-oriented evaluation of climate models, a clear understanding of the processes responsible for polar climate changes, and a reduction in uncertainty associated with model projections. This quantification can be performed using a simple and consistent approach that is valid for a wide range of feedbacks, offering the opportunity for more systematic feedback analyses and a better understanding of polar climate changes.