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By using panel data of 15 Chinese manufacturing industries over the 2005-2014 period from OECD TiVA and WIOD databases, the impact of China's GVCs participation on labor productivity is estimated. We find that while the productivity elasticity of the share of sector's foreign value added relative to sector's exports known as sector backward linkages is negative, that relative to China's gross exports named structure backward linkage is positive. As the annual average growth rates of both backward linkages are negative, China's backward linkages have contributed to productivity growth of 6.41% per year on average. We find that the positive productivity elasticity of the share of domestic intermediate goods embodied in exports of third countries relative to sector's exports, named sector forward linages together with a positive annual average growth rate, and that relative to China's exports named structure forward linkages together with a negative annual average growth rate, have increased productivity of 1.97% per year on average. We find finally that GVCs position is improved from 0.3 in 2005 to 0.7 in 2014. China's GVCs participation exerted positive productivity effects via optimizing resource allocation inside sectors towards more efficiency ones, via moving up from low productivity backward linkages to higher productivity forward linkages and via improving its position. This diminished the risk to be entrenched in low-profitability low productivity growth GVCs activities in China. However, the productivity contribution of backward linkages 3 times higher than that of forward linkage suggests that the future positive productivity impact of GVCs moving up may be much more difficult in a less favorable context (trade war between China and USA, reindustrialization and trade protection related to Covid-19 for example).

The Covid-19 pandemic upset both the economies of most countries, but also the field of medical science. As never, public opinion has interfered in the choice of therapeutic trials as evidenced by the controversies surrounding protocols using hydroxychloroquine. The public's choice for these treatments is explained as the application of a kind of individual "Pascal's wager". This article analyses the formation of the belief system of individuals by applying ambiguity theory's insights and information entropy. It shows that the public's choices are the result of efficient communication strategies chosen by these treatments' promoters.

The worldwide COVID-19 pandemic has affected the tourism sector by closing borders, reducing both the transportation of tourists and tourist demand. Developing countries, such as Tanzania, where the tourism sector contributes a high share to gross domestic product, are facing considerable economic consequences. Tourism interlinks domestic sectors such as transport, accommodation, beverages and food, and retail trade and thus plays an important role in household income. Our study assessed the macroeconomic impacts of COVID-19 on the tourism sector and the Tanzanian economy as a case study of an impacted developing economy. We used a computable general equilibrium model framework to simulate the economic impacts resulting from the COVID-19 pandemic and quantitatively analysed the economic impacts.

The author greatly acknowledges the generous support and assistance by FFJ/Michelin Foundation for the work.; This study searches for French urban mobility practices with the dilemma of planned versus lived spaces with a focus on the specific urban planning practice of pedestrianization. The contradictory interplay of residential, commercial and transport-led mobility is studied in Paris through direct observation, primary and secondary data collection. Moreover, the possible impacts of the on-going pandemic on this interplay of personal mobility, residential mobility and commercial mobility is recognized as a major factor –a game changer– in the Paris study. The Paris study findings are compared to Japanese pedestrianization practices from a perspective of municipally-led and gentrification-induced mobility practices as part of the urban neoliberal agenda.The Paris field study was made from February to June 2021. It composed mainly of an online survey with Paris (Île-de-France) residents and a corresponding paper survey with shopkeepers of three local shopping streets in Paris, including Rue Montorgueil-Rue des Petits Carreaux (in 2nd arrondissement), Rue Cler (in 7th arrondissement) and Rue Daguerre (in 14th arrondissement). Both surveys were translated into French and had multiple choice questions regarding the respondent’s personal situation, daily mobility habits and ideas on municipal pedestrianization efforts. The shop survey also had questions on the type of commerce, the effects of COVID-19 on one’s business and ideas on the effects of shopping street pedestrianization on one’s business in terms of number of customers, sales and shop value. The online resident survey was responded to by 119 people. The shop survey was done on Rue Montorgueil (31), Rue des Petits Carreaux (11), Rue Cler (25), Rue Daguerre (45), and the side streets of these shopping streets (9) on paper with the willing shopkeepers, who amounted to 121 altogether. Although the small size of the study surveys is a limitation of this study, the additional oral communication with the English-speaking shopkeepers about mobility and pedestrianization practices in Paris helped to mitigate this limitation. The online resident survey had been kept on purpose at Paris (Île-de-France) level with the intention of getting as much opinion as possible of Parisians on municipal pedestrianization efforts. The survey analysis that had been conducted at two different geographical levels—Paris (Île-de-France) and specific local shopping streets—on purpose indicated that Parisians can take a different stance against the on-going changes in the urban mobility regime of Paris, depending on their outlook as a resident or a local business. In that sense, their attitudes are not carved in stone, but they are quite flexible. Furthermore, the application of nonparametric tests of Chi-square test of independence and Fisher’s exact test indicated statistically significant relationships among the data variables, such as age and ideas on pedestrianization (resident survey); duration of residence in Paris (Île-de-France) and ideas on pedestrianization (resident survey); and place of residence and mode of transport to work (shop survey). Additional critical comments were made by some of the shopkeepers on Rue Cler and Rue Daguerre. Pedestrianization seems to create common problems for shops’ regular product deliveries, when their customers want to make large purchases at once, or if they have luggage (as mentioned by hoteliers) in particular. A couple of shopkeepers also heavily criticized a lack of municipal support for local independent businesses, and urban planners who did not ask about their opinions regarding their street’s pedestrianization as well as a wrong prioritization of pressing urban issues. Despite all these significant critiques, the study also found enormous support for the municipal pedestrianization efforts. This study also looked at the real estate values by taking a snapshot of Paris apartment and shop values on two online sites, including: paris-housing.com and thestorefront.com to search for a possible connection between higher than average real estate prices, used as a proxy for gentrification and pedestrianization. The study acknowledges that private agencies may modulate their database and housing offers in accordance with a specific group of customers, hence their online catalogues may not represent the actual price averages as a whole. Yet other potential databases were out of reach for the researcher because of language and economic barriers. Based on this simple real estate data analysis, although the m2 rental values for apartments and shops that are located near pedestrian streets seem to be higher than the Paris average in a few cases, this is not enough to conclude that there is a statistically significant relationship between pedestrianization and real estate values. It would require a consideration of the mediating factors, such as the assets’ own qualities, centrality, convenience, and availability of facilities and greenery nearby to cancel out their effects besides a more long-term data to compare the pre- and post-pedestrianization rental values. The paper concludes that despite the common tendency to prioritize active transport modes, such as walking and bicycling by the urban mobility regimes belonging to countries at different development levels, the mobility-based urban change policy and practices cause differing outcomes in different contexts. These can range from the more beneficial, such as resilience against environmental and health crises to the more controversial, including involuntary moves of people and shops (displacement) and more expensive, over-aestheticized cities of consumption (touristification and gentrification) with strengthened socio-economic demarcation lines between their citizens. The research underlines the possibility that popular urban policy discourses, in this case, a pedestrian-friendly city might create just the opposite ends depending on their way of implementation and contextual factors. At the same time, this paper argues that only by taking into account the opposite political stances of: the right to stay put, place-making, dwelling, anti-displacement, occupy and slow city movements in relation to the use of city space just as much as fluidity, liquidity, and mobility, more even forms of urban mobility can be achieved in the crisis-tested contemporary cities of the world.

The COVID-19 pandemic has prompted numerous fluid dynamical simulations of the propagation of potentially virus-laden respiratory droplets. While these studies have highlighted the apparent sensitivity of the numerical results to the sizes of the emitted droplet and the local humidity, many of them are still performed in stagnant air, i.e., without any external air flow. This very short note demonstrates, on the basis of coarse-grained fluid dynamical simulations in a simple generic setting, that even modest winds or air draughts strongly impact the risks of short-ranged transmission via droplets. The induced dispersion of droplets may contribute to explaining the lower risks of viral transmission experienced outdoors, even at short range.

International audience; In response to the ongoing COVID-19 pandemic caused by SARS-CoV-2, governments are taking a wide range of non-pharmaceutical interventions (NPI). These measures include interventions as stringent as strict lockdown but also school closure, bar and restaurant closure, curfews and barrier gestures i.e . social distancing. Disentangling the effectiveness of each NPI is crucial to inform response to future outbreaks. To this end, we first develop a multi-level estimation of the French COVID-19 epidemic over a period of one year. We rely on a global extended Susceptible-Infectious-Recovered (SIR) mechanistic model of the infection including a dynamical (over time) transmission rate containing a Wiener process accounting for modeling error. Random effects are integrated following an innovative population approach based on a Kalman-type filter where the log-likelihood functional couples data across French regions. We then fit the estimated time-varying transmission rate using a regression model depending on NPI, while accounting for vaccination coverage, apparition of variants of concern (VoC) and seasonal weather conditions. We show that all NPI considered have an independent significant effect on the transmission rate. We additionally demonstrate a strong effect from weather conditions which decrease transmission during the summer period, and also estimate increased transmissibility of VoCs.

The model descibes the epidemic dynamics of Covid-19 in a population after vaccination. Using the maximum principale, our goal is to prove the existence of an optimal strategy such that it minimize the number of infected people after vaccination. Finally, some numerical results are provided.

A possible explanation based on first principles for the appearance of the Omicron variant of the SARS-CoV-2 virus is proposed involving coinfection with HIV. The gist is that the resultant HIV-induced immunocompromise allows SARS-CoV-2 greater latitude to explore its own mutational space. This latitude is not withoutr estriction, and a specific biophysical constraint is explored. Specifically, a nearly two- to five-fold discrepancy in backbone hydrogen bonding is observed between sub-molecules in Protein Data Bank files of the spike glycoprotein yielding two conclusions: mutagenic residues in the receptor-binding subunit of the spike much more frequently do not participate in backbone hydrogen bonds; and a technique of viral escape is therefore to remove such bonds within physico-chemical and functional constraints. Earlier work, from which the previous discussion is entirely independent, explains these phenomena from general principles of free energy, namely, the metastability of the glycoprotein. The conclusions therefore likely hold more generally as principles in virology.

Using the UK household longitudinal survey, we uncover a positive effect of work from home on life satisfaction, which is driven by partnered people and those without children at home. Concerning mental health, there is no average effect of telework, except for those living in rural areas, but this hidesa dynamic evolution, as mental health initially deteriorates in the first months of telework, but improves after a period of adaptation, especially the feeling of being useful, of being a worthy person, and of being able to concentrate.

Europe is confronted with a large COVID-19 wave caused by the Delta variant in autumnwinter 2021-2022. Using a mathematical model applied to Metropolitan France, we find that the hospitalisation peak might be reduced by 25%, 36% and 43% if boosters are administered to those aged 65+, 50+ or 18+, respectively, with a delay of 5 months between the second and third dose. Ten percent reduction in transmission rates might further reduce peak size by 41%, indicating that even small increases in protective behaviours may play a critical role to mitigate the wave.Most European countries have experienced an important rise in SARS-CoV-2 infections and hospitalisations in the Autumn 2021. In response to this resurgence and to the reported partial decay of immunity, countries have started administering vaccine booster doses, relying on different eligibility criteria. Here, we present modelling analyses assessing different administration strategies for booster doses that informed the recommendations of the French National Immunization Technical Advisory Group (Haute Autorité de Santé) in the context of Metropolitan France.