The Geographical Deconcentration of Scientific Activity (1987-2007)

Texte intégral à l'adresse : http://sticonference.org/Proceedings/vol1/Grossetti_Geographical_348.pdfTraditional research on "world cities" tends to develop the idea that large, inter-connected agglomerations can better take advantage of international competition. This suggests that we should observe an increasing concentration of activities in these cities at the expense of smaller ones. Among analyses using measures based on scientific publications, certain studies support this hypothesis. Others however, show that in certain countries such as China, an opposite trend is emerging; the largest cities are undergoing a relative decline in the country's scientific activities. To go beyond this seeming contradiction, this paper provides a global analysis of all countries having papers in Thomson Reuters 'Web of Science' over the period 1987-2007. The addresses -present in each article- were geo-coded and then grouped into agglomerations. The result of our analysis is unambiguous: deconcentration is clearly the dominant trend -both: globally and within countries-, despite some rare exceptions for which explanations are suggested

Cities and the geografical deconcentration of scientific activity : A multilevel analysis of publications (1987-2007)

International audienceMost current scientific policies incorporate debates on cities and the geographic organisation of scientific activity. Research on 'world cities' develops the idea that interconnected agglomerations can better take advantage of international competition. Thus, the increasing concentration of activities in these cities at the expense of others could be observed by certain scholars using measures based on scientific publications. Others, however, show that an opposite trend is emerging: the largest cities are undergoing a relative decline in a country's scientific activities. To go beyond this seeming contradiction, this paper provides a global analysis of all countries with papers in the Web of Science over the period 1987-2007. The author's addresses were geocoded and grouped into agglomerations. Registering of papers was based on the fractional counting of multi-authored publications, and the results are unambiguous: deconcentration is the dominant trend both globally and within countries, with some exceptions for which explanations are suggestedBeijing (Pékin), Tokyo, Paris, New York, Séoul, Londres... les grands foyers de la science pèsent moins que par le passé du fait d'une déconcentration géographique au niveau mondial. Tel est le résultat de l'analyse statistique systématique menée par des scientifiques du Laboratoire interdisciplinaire solidarités, sociétés, territoires (CNRS/Université de Toulouse II-Le Mirail/EHESS) sur des millions d'articles de publications scientifiques, édités entre 1987 et 2007 dans des milliers de revues scientifiques recensées par le Web of Science. Ces travaux sont les premiers à s'intéresser à la géographie de la science au niveau de l'ensemble des villes mondiales

Mediator head subcomplex Med11/22 contains a common helix bundle building block with a specific function in transcription initiation complex stabilization

Mediator is a multiprotein co-activator of RNA polymerase (Pol) II transcription. Mediator contains a conserved core that comprises the ‘head’ and ‘middle’ modules. We present here a structure–function analysis of the essential Med11/22 heterodimer, a part of the head module. Med11/22 forms a conserved four-helix bundle domain with C-terminal extensions, which bind the central head subunit Med17. A highly conserved patch on the bundle surface is required for stable transcription pre-initiation complex formation on a Pol II promoter in vitro and in vivo and may recruit the general transcription factor TFIIH. The bundle domain fold is also present in the Mediator middle module subcomplex Med7/21 and is predicted in the Mediator heterodimers Med2/3, Med4/9, Med10/14 and Med28/30. The bundle domain thus represents a common building block that has been multiplied and functionally diversified during Mediator evolution in eukaryotes

Green Edge ice camp campaigns : understanding the processes controlling the under-ice Arctic phytoplankton spring bloom

The Green Edge initiative was developed to investigate the processes controlling the primary productivity and fate of organic matter produced during the Arctic phytoplankton spring bloom (PSB) and to determine its role in the ecosystem. Two field campaigns were conducted in 2015 and 2016 at an ice camp located on landfast sea ice southeast of Qikiqtarjuaq Island in Baffin Bay (67.4797∘ N, 63.7895∘ W). During both expeditions, a large suite of physical, chemical and biological variables was measured beneath a consolidated sea-ice cover from the surface to the bottom (at 360 m depth) to better understand the factors driving the PSB. Key variables, such as conservative temperature, absolute salinity, radiance, irradiance, nutrient concentrations, chlorophyll a concentration, bacteria, phytoplankton and zooplankton abundance and taxonomy, and carbon stocks and fluxes were routinely measured at the ice camp. Meteorological and snow-relevant variables were also monitored. Here, we present the results of a joint effort to tidy and standardize the collected datasets, which will facilitate their reuse in other Arctic studies

X-ray structure of a domain-swapped dimer of Ser46-phosphorylated Crh from Bacillus subtilis

International audienc

Identification, structure, and functional requirement of the Mediator submodule Med7N/31

Mediator is a modular multiprotein complex required for regulated transcription by RNA polymerase (Pol) II. Here, we show that the middle module of the Mediator core contains a submodule of unique structure and function that comprises the N-terminal part of subunit Med7 (Med7N) and the highly conserved subunit Med31 (Soh1). The Med7N/31 submodule shows a conserved novel fold, with two proline-rich stretches in Med7N wrapping around the right-handed four-helix bundle of Med31. In vitro, Med7N/31 is required for activated transcription and can act in trans when added exogenously. In vivo, Med7N/31 has a predominantly positive function on the expression of a specific subset of genes, including genes involved in methionine metabolism and iron transport. Comparative phenotyping and transcriptome profiling identify specific and overlapping functions of different Mediator submodules

La diversification des espaces de production du savoir

Texte intégral à l'adresse : http://ceriscope.sciences-po.fr/puissance/content/part2/la-diversification-des-espaces-de-production-du-savoir ISSN 2115-4856Une analyse statistique systématique a été menée par des scientifiques du Laboratoire interdisciplinaire solidarités, sociétés, territoires (CNRS/Université de Toulouse II-Le Mirail/EHESS) sur des millions d'articles de publications scientifiques, édités entre 1987 et 2007 dans des milliers de revues scientifiques recensées par le Web of Science. Cette méthodologie de recherche, qui permet de localiser la production scientifique mondiale, a permis de définir une géographie de la science au niveau de l'ensemble des villes de la planète. Cette étude conclue que contrairement à l'idée qui prévaut dans beaucoup de débats et de décisions sur les politiques scientifiques, la tendance globale n'est pas à la concentration des activités scientifiques dans des " villes mondiales ". Elle observe d'abord une perte d'hégémonie des pays les plus anciennement présents dans les bases de données bibliographiques, avec une croissance particulièrement importante des pays asiatiques (Chine, Corée du Sud, Taiwan), mais plus largement de très nombreux pays " émergents ". Cette évolution contribue à diversifier les lieux de production des publications recensées. On observe ensuite au sein de nombreux pays, indépendamment de l'évolution globale de la production scientifique nationale, une tendance à la déconcentration par croissance supérieure de villes " secondaires " (Russie, France, Espagne, Royaume-Uni, Chine, etc.). Les pays les plus anciennement " déconcentrés " (Etats-Unis, Canada, Allemagne par exemple) ont une géographie scientifique plutôt stable. Les pays qui connaissent un processus de concentration sont rares et pour chacun d'entre eux, cette situation s'explique par leurs évolutions démographiques, économiques et scientifiques. Les espaces de production du savoir sont donc, à toutes les échelles considérées, en voie de diversification

La diversification des espaces de production du savoir

La plupart des politiques scientifiques actuelles intègrent une réflexion sur les villes et l’organisation géographique de l’activité scientifique. Dans la lignée des travaux sur les world cities, l’idée s’est imposée que les grandes agglomérations connectées entre elles parviennent à tirer un meilleur parti de la compétition internationale. On observerait donc dans ces villes une tendance à la concentration croissante des activités. Parmi les travaux utilisant des mesures fondées sur les publications scientifiques, certains soutiennent cette hypothèse, alors que d’autres montrent que pour certains pays, comme la Chine, on observe plutôt la tendance inverse, les plus grandes agglomérations voyant leur poids relatif régresser dans les activités scientifiques du pays. Cet article présente les résultats d’une recherche portant sur l’ensemble des activités scientifiques mondiales. Les contributeurs des articles recensés par le web of science ont été géocodés, puis regroupés en agglomérations. L’analyse de ces données est sans ambiguïté, c’est bien la tendance à la déconcentration qui s’impose à l’échelle mondiale comme à l’intérieur des pays, même si l’on observe quelques rares exceptions, pour lesquelles des explications sont avancées

Overexpression of toll-like receptor 4 amplifies the host response to lipopolysaccharide and provides a survival advantage in transgenic mice

Toll-like receptors are transmembrane proteins that are involved in the innate immune recognition of microbial constituents. Among them, Toll-like receptor 4 (Tlr4) is a crucial signal transducer for LPS, the major component of Gram-negative bacteria outer cell membrane. The contribution of Tlr4 to the host response to LPS and to infection with virulent Salmonella typhimurium was studied in four transgenic (Tg) strains including three overexpressing Tlr4. There was a good correlation between the level of Tlr4 mRNA expression and the sensitivity to LPS both in vitro and in vivo: Tg mice possessing the highest number of Tlr4 copies respond the most to LPS. Overexpression of Tlr4 by itself appears to have a survival advantage in Tg mice early during infection: animals possessing more than two copies of the gene survived longer and in a greater percentage to Salmonella infection. The beneficial effect of Tlr4 overexpression is greatly enhanced when the mice present a wild-type allele at natural resistance-associated macrophage protein 1, another critical innate immune gene involved in resistance to infection with Salmonella. Tlr4 and natural resistance-associated macrophage protein 1 exhibit functional epistatic interaction to improve the capacity of the host to control bacterial replication. However, this early improvement in disease resistance is not conducted later during infection, because mice overexpressing Tlr4 developed an excessive inflammatory response detrimental to the host