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1.
Les observatoires occidentaux se transforment en véritable usine scientifique à partir du milieu du 19e siècle. L'astrométrie symbolise ce passage à une économie industrieuse des pratiques scientifiques. Le chronographe imprimant, qui permet de réduire les équations personnelles des observateurs, s'impose, d'abord aux Etats-Unis, puis en Angleterre, en instrument-emblème de cette transformation profonde. En France, les initiatives de l'astronome Liais restent prototypiques. Ce n'est qu'au début du 20e siècle, par les voies détournées de l'observatoire d'Hendaye et de l'abbé Verschaffel, que le chronographe imprimant fait son retour et conquiert les espaces savants. La centralisation excessive de l'astronomie française, l'autoritarisme du directeur de l'Observatoire de Paris Urbain Le Verrier, et la faiblesse du marché des instruments expliquent pourquoi le chronographe imprimant n'a fait souche que très tardivement en France.  相似文献   

2.
The authors confirm the analogy between Gc and DBP as a result of analytic studies by isoelectrofocusing and labeling of Gc with 3H vitamin D3. The presence of a relationship between Gc polymorphism and the amount of sunshine in a given region is discussed.  相似文献   

3.
At the beginning of the 1730s René Antoine Ferchault de Réaumur published two long memoirs on a new type of thermometer equipped with a specially calibrated scale — known ever since as the Réaumur scale. It became one of the most common ‘standardized’ thermometers in Europe until the late nineteenth century. What made this thermometer so successful? What was it specifically? I will first argue that the real Réaumur thermometer as an instrument was a fiction, a ghost — an idealized instrument. On paper, it was theoretically flawless. In reality, the standardized Réaumur thermometer was most likely never achieved. This article shows that its success was essentially due to a recontextualisation from theoretical natural philosophy — Réaumur's principle of uniformity — to: 1) the context of artisanal knowledge and practices and 2) the context of making and reporting in the Mémoires de l'Académie royale des sciences actual measurements done in the field (in Paris at the Observatory, in Provincial France, in the Colonies, and in the rest of Europe). Réaumur's thermometer was essentially a theoretical method to which was associated a particular scale. It was the instrument's reification for market consumption and fieldwork that gave this specific type of thermometer materiality and authority. Although most Réaumur thermometers ever made were strikingly different from one another, over time the thermomètre de Réaumur designation became a brand, a seal of approval born from customary artisanal practices and cultural habitudes.  相似文献   

4.
A feature of mid-nineteenth century scientific debates in France on the subject of plant nutrition was the rivalry, at times acrimonious, between Jean Baptiste Boussingault and Georges Ville. It started in 1848 when Ville was demonstrator to Boussingault, who held one of the two chairs of agriculture at the Conservatoire des Arts et Métiers. A study of their disputes serves to illustrate their mutual incompatibility, exacerbated by the patronage extended to Ville by his step-brother, Louis Napoléon Bonaparte, afterwards Napoléon III. Their disputes were not merely the result of personal differences but also accompanied the development of two concepts of plant nutrition, namely the rôle of atmospheric nitrogen. and its possible assimilation by plants, and the chemical nature of plant nutrients, especially nitrates and phosphates.  相似文献   

5.
The European rabbit (Oryctolagus cuniculus) is now widely distributed throughout the world as a result of transportation by man. The original populations, however, were confined to southern France and Spain. In order to investigate the role of human intervention in determining the genetic diversity of rabbit populations, we are studying the origin of rabbits introduced onto a small Mediterranean island (Zembra) near Tunis over 1400 years ago, by examining ancient DNA extracted from rabbit bones found both on Zembra and on the European mainland. Ancient DNA was successfully extracted from rabbit bones found at two archaeological sites dated to at least the Early Bronze Age (more than 3500 years ago) in south-central France, and compared to that found in modern mainland and island populations using a small variable region of the cytochromeb gene. The results confirm that the Zembra Island population is descended from that present over 1400 years ago. The technical aspects of DNA extraction from bones and the implications of this type of research for determining the origin of introduced rabbit populations are discussed.  相似文献   

6.
An examination of British and French weights exchanged between the Royal Society and the Académie royale des sciences in the 1730s has led to a re‐assessment of the Elizabethan troy standards from the Exchequer and the suggestion that the mass of the troy pound has been revised upwards. In turn this is used to support the idea of an evolutionary relationship between the early bullion ounces of England, France, and the Low Countries.  相似文献   

7.
Relations between J. A. C. Chaptal, pioneer of heavy chemical industry in France, and A. L. Lavoisier, reformer of chemical theory, are examined in the light of unpublished correspondence they exchanged in the period 1784–1790. The letters, together with Chaptal's early publications, allow a reconstruction of his conversion to Lavoisier's antiphlogistic chemistry. They also reveal a series of petitions that Chaptal made to Lavoisier, in the latter's official capacity as a director of the Régie des poudres et salpêtres, for relief from the controlled price of saltpetre for his acid works in Languedoc. Finally, the relationship is explored as a window on the interplay between chemical theory and industrial practice during the period of the Industrial Revolution.  相似文献   

8.
For many years, scientific heritage has received attention from multiple actors from different spheres of activity—archives, museums, scientific institutions. Beyond the heterogeneity revealed when examining the place of scientific heritage in different places, an authentic patrimonial configuration emerges and takes the form of a nebula of claims and of accomplishments that result, in some cases, in institutional and political recognition at the national level, in various country all around the world. At the international level, the creation of the international committee dedicated to University Museums and Collections (UMAC) within the International Council of Museums (ICOM) certainly testified from this raising interest in academic heritage and the existence of a specific community concern with it.This article presents numerous initiatives for the preservation of scientific heritage in France, with the goal of analysing the relationship scientists have with their heritage. We argue that scientific communities have a special relationship with heritage, which is characterized by a number of ambiguities. We show that such ambivalences allow analysis of identity, discipline, professional, and social issues operative in defining heritage and being redefined by heritage. To explore these dimensions, we have chosen to present three different case studies. The first traces the institutional uses of heritage by a scientific institution, the Commissariat à l’énergie atomique (CEA), through the transformation of the first French atomic reactor (ZOE) into a museum. The second example describes the initiatives of French astronomers from the mid-1990s to construct a national programme for the protection of astronomy heritage. Lastly, we recount the case of universities, with the example of the Université de Strasbourg.  相似文献   

9.
Considered in its historical context, conventionalism is quite different from the way in which it has been caricatured in more recent philosophy of science, that is, as a conservative philosophy that allows the preservation of theories through arbitrary ad hoc stratagems. It is instead a liberal outgrowth of Comtean positivism, which broke with the Reidian interpretation of the Newtonian tradition in France and defended a role for hypotheses in the sciences. It also has roots in the social contract political philosophy of Renouvier, who explicitly drew the analogy between conventions in political life and the conventional acceptance of hypotheses in the sciences, and conceived a philosophy that permits scientists to set aside foundational worries and explore new ideas. Although Poincaré and Renouvier may have hesitated to accept certain then recent developments in mathematics and the sciences such as non-Euclidean geometries, this conservatism cannot necessarily be attributed to their conventionalism. It may instead reflect the engineering background they shared with Comte, which emphasizes practical applications. Although Renouvier and Poincaré may have seen no practical use for these new ideas, unlike Comte they did not prohibit others from pursuing them, reflecting conventionalism's more liberal attitude toward recent developments in the sciences.  相似文献   

10.
Sous la Révolution, la conjoncture politique et militaire et l'échec de la poudre de muriate (chlorate) devaient conduire la France à privilégier la rationalisation des procédés de fabrication pour tenter d'accroître la portée des armes. En 1796, la poudre ronde de J. P. Champy (1744–1816), successeur de Lavoisier à la tête du service des Poudres et salpêtres, parut approcher de la poudre idéale: pour un prix de revient réduit, elle offrait une puissance suffisante et une sécurité optimale de fabrication et d'emploi. Malgré l'avis des experts scientifiques et militaires, sa production cessa pourtant à la suite d'un blocage politico-administratif. A la fin de l'Empire, J. S. Champy (1778–1845), perfectionna le procédé de son père pour en faire le premier système de production mécanisé, dont l'introduction devait modifier l'organisation du travail et la configuration des poudreries créées sous la Restauration. Le succès du système conduisit paradoxalement à son échec après une décennie de production qui resta toujours expérimentale: la poudre ronde remettait en cause les techniques métallurgiques en faisant éclater les canons. La publication inédite du premier rapport d'expertise de ce procédé (1813) fournit l'occasion de suivre les origines et l'évolution d'un système qui annonce la mécanisation de l'industrie poudrière au XIXe siècle, tout en se présentant clairement comme l'aboutissement des procédés révolutionnaires de l'an II. Elle permet aussi de s'interroger sur les critères et le statut de l'expertise, au moment même où l'analyse chimique de la poudre commence avec Proust, Gay-Lussac et Brianchon.  相似文献   

11.
Résumé Une activité considérable de la 3,4-dihydroxyphénylealanine (DOPA) décarboxylase a été démontrée chez un transplantable mélanome malin du hamster. Après l'injection intrapéritonéale du précurseur de la dopamine, l'amine nouveau-formée était trouvée dans toutes les tumeurs. L'inhibition de la DOPA décarboxylase par traitement des hamsters avec α-méthyle-DOPA n'a pas influé sur le progrès des tumeurs.

This study was supported by grants from Riksf?reningen mot cancer, Stockholm, and from the Léonie Deshayes' Foundation, Lund. Melanoma-bearing Syrian hamsters were generously supplied by Prof.H. Storck, Zürich (Switzerland). The supply of α-methyl DOPA from Merck, Sharp and Dohme (USA) is gratefully acknowledged.  相似文献   

12.
Summary InCulex pipiens mosquitos from Southern France, resistance to the organophosphorus insecticide chlorpyrifos is due to the dominant allele (Chl R) of an autosomal gene. TheChl gene is localized between thea-Gpd andEst-2 loci at 26.8 and 5.8 units of crossing-over respectively.  相似文献   

13.
Historiography of the development of probability and statistics in the Russian Empire focusses on the contributions of the central figure Pafnutiy Lvovich Chebyshev (1821–1894) and his successors. The purpose of this article is to concentrate on an earlier period which culminates with Chebyshev, and specifically on two less-than-well-explored aspects: (1) The background and motivation for his activity in probability and statistics; (2) The French connections and influences on his work. The key figures in this account are A.F. Pavlovsky (1789–1875); M.V. Ostrogradsky (1801–1862); V.Y. Buniakovsky (1804–1889); N.D. Brashman (1796–1866); N.E. Zernov (1804–1862), S.G. Stroganov (1794–1882); P.S. de Laplace (1749–1827); A.L. Cauchy (1789–1857); I.J. Bienaymé (1796–1878); N.V. Khanykov (1819–1878); and, in Chebyshevs childhood, a governess and relation, Avdotiia Kvintillianovna Sukhareva. Chief among these, from the years of Chebyshevs maturity, are Buniakovsky and Bienaymé. The cultural contacts between France and the Russian Empire in the 19th century were strong, and these connections are particularly well-illustrated in this setting. (Received January 10, 1998)  相似文献   

14.
Summary Experiments are reported which tend to support the hypothesis that a single gene or gene complex may be responsible for inbreeding depression. The gene is located on the third chromosome.I thank R. Grantham and J.M. Legay (Lyon, France), C. Krimbas (Athens, Greece), D. Mohler (USA) and especially R. Milkman (USA) for helpful criticism and suggestions. The Laboratoire de Biométrie is associated with CNRS Laboratory No. 243.  相似文献   

15.
Summary Dibutyryl cyclic GMP did not affect basal, or carbachol stimulated secretion of α-amylase from rat pancreas. The nucleotide did not have a significant effect on45Ca release from the pancreas nor did it alter the response to carbachol. The dibutyryl analogue of cyclic GMP did not duplicate or alter the inhibitory effect of carbachol on3H-leucine incorporation into pancreatic trichloroacetic acid-precipitable protein.
Résumé L'effet du dibutyryl GMPc sur la sécrétion d'α-amylase, l'efflux du45Ca et la synthèse de nouvelles protéines dans le pancréas du rat, ont été étudiés. Le dibutyryl GMPc n'affecte ni la sécrétion d'enzyme basale ni celle stimulée par le carbachol. Le nucléotide n'a pas un effet significatif sur le relàchement du45Ca du pancréas et n'altère pas la réponse du carbachol. L'analogue ne mime pas et ne change pas l'effet du carbachol sur l'incorporation du3H-leucine dans les protéines précipitées par l'acide trichloroacétique.


Supported by a grant from the Medical Research Council of Canada. The authors acknowledge the secretarial aide of MissC. Picard.  相似文献   

16.
This paper investigates how and when pairs of terms such as “local–global” and “im Kleinenim Grossen” began to be used by mathematicians as explicit reflexive categories. A first phase of automatic search led to the delineation of the relevant corpus, and to the identification of the period from 1898 to 1918 as that of emergence. The emergence appears to have been, from the very start, both transdisciplinary (function theory, calculus of variations, differential geometry) and international, although the AMS-Göttingen connection played a specific part. First used as an expository and didactic tool (e.g. by Osgood), it soon played a crucial part in the creation of new mathematical concepts (e.g. in Hahn’s work), in the shaping of research agendas (e.g. Blaschke’s global differential geometry), and in Weyl’s axiomatic foundation of the manifold concept. We finally turn to France, where in the 1910s, in the wake of Poincaré’s work, Hadamard began to promote a research agenda in terms of “passage du local au general.”  相似文献   

17.
Résumé

Le cadran solaire analemmatique est présenté pour la première fois par un mathématicien français, appelé Vaulezard, dans un petit fascicule publié en 1640. Suit un deuxième ouvrage, plus complet, en 1644. Dernier venu, ce cadran attire l'attention d'importants savants tels que Foster et Lalande. Parfait dès le départ, il a néanmoins la singulière particularité d'inspirer diverses tentatives d'amélioration, plutôt infructueuses, et d'être à l'origine de quelques variétés de cadrans analemmatiques qui, elles, connaissent un franc succès. Nous apportons la preuve trigonométrique et, pour la première fois semble‐t‐il, la preuve géométrique de sa validité astronomique en suivant fidèlement la méthode de construction indiquée par Vaulezard. Nous effectuons, en outre, un survol aussi exhaustif que possible des différents modèles dérivés de ce cadran ainsi que de la littérature les concernant.

Summary

The analemmatic sundial was briefly presented for the first time in 1640 by the French mathematician Vaulezard and was described in more detail by him in 1644. The analemmatic dial is the last genuine sundial to be invented and it has attracted the attention of some important scholars such as Foster and Lalande. Although perfect from the very beginning, it had the unusual particularity of inspiring several unfortunate attempts at its improvement as well as being at the origin of a few other types of analemmatic dials, which met with a certain success. We provide here the trigonometric proof and for the first time, the geometric proof of its astronomical validity by closely following the construction method of Vaulezard. We also make a comprehensive survey of the different kinds of analemmatic sundials and of their literature.  相似文献   

18.
Résumé Chez des cobayes rendus hypothyro?diens au moyen de ladl-triiodothyrosine, la Réserpine diminue la consommation d'oxygène. Les résultats présentés suggèrent que la Réserpine agit comme un antagoniste de ladl-triiodothyrosine. L'action de l'hormone thyro?dienne (exogène ou endogène) sur la consommation d'oxygène est empêchée probablement par un mécanisme localisé à la périphérie.

Reserpine (Serpasil?) used in these experiments was generously supplied by Ciba Pharmaceutical Products, Inc., Summit, New Jersey.

This work was supported by a grant from Ciba Pharmaceutical Products, Inc.  相似文献   

19.
Résumé Observations sur la multiplication de deux particules différentes de virus dans le sérum de la sour's après infection par l'agent de LDH. Le fait que la grande particule a disparu du sérum sept semaines après l'infection suggère que la petite particule est responsable de la virémie persistante et du taux élevé de l'enzyme dans le sang des animaux infectés.

Supported by grant CA-05742-04 from the National Cancer Institute, National Institutes of Health, Public Health Service.  相似文献   

20.
Summary Cannabinoid content of a population ofCannabis sativa L. originating from Mexico and cultivated in France is studied. The statistical analysis of results shows how difficult it is to obtain homogenous and representative samples. This problem is correlated to genetic heterogeneity of seeds.

Les cultures ont été effectuées à l'Arboretum de Chèvreloup, France.

Les cultures ont été effectuées à l'Arboretum  相似文献   

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