The quantitative approach to business cycle in « X-Crise » group in the 1930's

To construct models and to apply quantitative techniques in order to explain the cyclical movements of the economy is one of the main aims of “X-Crise” group (nickname of “Centre Polytechnicien d'Etudes Economiques”) at the “Ecole Polytechnique” in Paris. Indeed, french polytechniciens' engineers hope that mathematical economics, and especially empirically based modelization, will be helpful first to build a true economic science, and second, to find solutions to the 1930's crisis. These hopes are developed in the methodological debate that Polytechniciens began even before the creation of the association X-Crise. They explain in particular their rejection of "pure” economics and their defence of an approach which mixes economic concepts, statistical facts and mathematical model – such as econometrics. Overall, these hopes are expressed through models constructed by X-Crise members, such as Polytechniciens like François Moch and Maurice Potron or non-polytechniciens like brothers Georges and Edouard Guillaume. Attempts were done to include business cycle in their models. But, finally, they failed to confront them to empirical data.French Engineers - Business Cycles - history of econometrics

French Engineers and the Machinery of Society: X-Crise and the Development of the first Macroeconomic Models in the Nineteen Thirties

The purpose of this article is to highlight the originality of X-Crise, an Ecole Polytechnique association formed in nineteen thirties' France. Firstly il analyses the factors leading the French engineers to look collectively, for the first time of their history, at the big politicoeconomic problems of their epoch. Two factors seem particularly relevant on this matter : their epistemology and value system on one hand, and their perception of the theoretical and political impotence at that time on the other hand.Secondly this paper presents the main original theoretical elements that arose from the group's deliberations. Among them, it exposes the Guillaume brothers' macroeconomic model [1932], one of the very first macroeconomic model produced in France, and Potron's first application to economics of Perron-Frobenius's theorem (Potron [1911] and [1935]).French Engineers - Macroeconomic models - Pragmatism - Mechanics - Perron-Frobenius's theorem

“Italian Economists of the 20th Century”, edited by Ferdinando Meacci, Cheltenham: Edward Elgar, 1998

This book contains twelve essays on some important Italian economists whose works were mostly published in the 20th century. The essays are written mostlty by non-Italian authors and deal with Vilfredo Pareto (by A. Kirman), Maffeo Pantaleoni (Peter Groenewegen), Enrico Barone (P. C. Dooley), Antonio De Viti de Marco (O. Kayaalp), Marco Fanno (R. Arena), Costantino Bresciani-Turroni (H. D. Kurz), Luigi Einaudi (F. Meacci), Piero Sraffa (B. Schefold), Franco Modigliani (C. Dangel), Paolo Sylos Labini (J. Halevi), Pierangelo Garegnani (G. Mongiovi), and L. Luigi Pasinetti (J. R. Teixeira). A short introduction by Ferdinando Meacci opens the volume and advances a suggestive hypothesis for a comprehensive interpretation of the evolution of Italian economic thought during the last century. This introduction is an attempt to treat the thoughts of the twelve economists as a sample from which to infer a brief outline of Italian economics in the 20th century and of its links with economics in general. This outline is sketched in two glimpses. One looks at the economists one after the other according to the period in which they lived (and is accordingly called ‘vertical’). The other looks at them one next to the other according to the methods they have in common (and is accordingly called ‘horizontal’).Italian economists, history of economics, vertical and horizontal

The quantitative approach to business cycle in « X-Crise » group in the 1930's

To construct models and to apply quantitative techniques in order to explain the cyclical movements of the economy is one of the main aims of “X-Crise” group (nickname of “Centre Polytechnicien d'Etudes Economiques”) at the “Ecole Polytechnique” in Paris. Indeed, french polytechniciens' engineers hope that mathematical economics, and especially empirically based modelization, will be helpful first to build a true economic science, and second, to find solutions to the 1930's crisis. These hopes are developed in the methodological debate that Polytechniciens began even before the creation of the association X-Crise. They explain in particular their rejection of "pure” economics and their defence of an approach which mixes economic concepts, statistical facts and mathematical model – such as econometrics. Overall, these hopes are expressed through models constructed by X-Crise members, such as Polytechniciens like François Moch and Maurice Potron or non-polytechniciens like brothers Georges and Edouard Guillaume. Attempts were done to include business cycle in their models. But, finally, they failed to confront them to empirical data

PlantCARE, a plant cis-acting regulatory element database

PlantCARE is a database of plant cis-acting regulatory elements, enhancers and repressors. Besides the transcription motifs found on a sequence, it also offers a link to the EMBL entry that contains the full gene sequence as well as a description of the conditions in which a motif becomes functional. The information on these sites is given by matrices, consensus and individual site sequences on particular genes, depending on the available information

Removal of Sea Lettuce, Ulva spp., in Estuaries to Improve the Environments for Invertebrates, Fish, Wading Birds, and Eelgrass, Zostera marina

Mats (biomasses) of macroalgae, i.e. Ulva spp., Enteromorpha spp., Graciolaria spp., and Cladophora spp., have increased markedly over the past 50 years, and they cover much larger areas than they once did in many estuaries of the world. The increases are due to large inputs of pollutants, mainly nitrates. During the warm months, the mats lie loosely on shallow sand and mud flats mostly along shorelines. Ulva lactuca overwinters as buds attached to shells and stones, and in the spring it grows as thalli (leaf fronds). Mats eventually form that are several thalli thick. Few macroinvertebrates grow on the upper surfaces of their thalli due to toxins they produce, and few can survive beneath them. The fish, crabs, and wading birds that once used the flats to feed on the macroinvertebrates are denied these feeding grounds. The mats also grow over and kill mollusks and eelgrass, Zostera marina. An experiment was undertaken which showed that two removals of U. lactuca in a summer from a shallow flat in an estuarine cove maintained the bottom almost free of it

Competing Voices of the Drive to Planning? The Cooperatist Engagement with Corporatism in Romania

The article inquiries into the interplay between the discourses of cooperatism and corporatism in pre-communist Romania, by locating both trends within the fold of the drive to economic planning prevalent in the 1930’s and relating them to the development of syndicalism and social policies over the long run. The sophisticated engagement of the cooperatist theorist Gromolsav Mladenatz with the spread of corporatist ideas and practice in Europe is placed at the center of the account and contextualized in the national ideological and political setting, with an emphasis on his efforts to explore the validity of the claims advanced by the contemporary economic theory with a right-wing orientation to strike a revolutionary path away from liberal capitalism, as well as on his largely negative assessment of the same claims. Mladenatz’s own searches for a way out of the economic predicament of the time is shown to have led him, at the end of the period covered, towards a departure from the tenets of dirigisme (otherwise shared, on all accounts, by the cooperatist and corporatist camps). The corresponding contextualization of Mihail Manoilescu’s view of corporatism, by relating it to the various strands of the Romanian politics of professional representation and to all the ideological attitudes of relevance, is the larger objective targeted all throughout

The social philosophy of Georges Sorel

This item was digitized by the Internet Archive

Carbonaceous molecules in the oxygen-rich circumstellar environment of binary post-AGB stars: C_{60} fullerenes and polycyclic aromatic hydrocarbons

Context. The circumstellar environment of evolved stars is generally rich in molecular gas and dust. Typically, the entire environment is either oxygen-rich or carbon-rich, depending on the evolution of the central star. Aims. In this paper we discuss three evolved disc sources with evidence of atypical emission lines in their infrared spectra. The stars were taken from a larger sample of post-AGB binaries for which we have Spitzer infrared spectra, characterised by the presence of a stable oxygen-rich circumbinary disc. Our previous studies have shown that the infrared spectra of post-AGB disc sources are dominated by silicate dust emission, often with an extremely high crystallinity fraction. However, the three sources described here are selected because they show a peculiar molecular chemistry. Methods. Using Spitzer infrared spectroscopy, we study in detail the peculiar mineralogy of the three sample stars. Using the observed emission features, we identify the different observed dust, molecular and gas species. Results. The infrared spectra show emission features due to various oxygen-rich dust components, as well as CO2 gas. All three sources show the strong infrared bands generally ascribed to polycyclic aromatic hydrocarbons. Furthermore, two sample sources show C60 fullerene bands. Conclusions. Even though the majority of post-AGB disc sources are dominated by silicate dust in their circumstellar environment, we do find evidence that, for some sources at least, additional processing must occur to explain the presence of large carbonaceous molecules. There is evidence that some of these sources are still oxygen-rich, which makes the detection of these molecules even more surprising.Comment: Accepted for publication in Astronomy and Astrophysics, 10 pages, 7 figure