Agronomists and accounting. The beginnings of capitalist rationalisation on the farm (1800-1850)

At the dawn of the nineteenth century numerous debates took place on the development of capita-list agriculture and the ways of making as much profit as possible from farm land. Until now this subject has hardly been examined and is unique in that it pertains to the economic history of agriculture, the history of agronomy and the history of managerial thinking. This article aims to highlight the usage of double-entry accounting for agronomic experiments in the first half of the nineteenth century, as well as the significance of the results and the way these were debated. Our aim is to present the authors’ reasons and the role played by bookkeeping in the construction of economically rational knowledge and reasoning. Thus we will bring to light two mechanisms which are common to this accounting quantification drive: data tabulation and the inclusion of data in balance sheets, making it possible to compare inputs and outputs in production processes

Écritures du travail et savoir paysans, Aperçu historique et lecture de pratiques. Les agendas des agriculteurs

Prenant comme objet d'étude les écrits du travail, cette recherche entend apporter un éclairage sur les modes de construction des savoir paysans. Son ambition est de mettre au jour des pratiques scripturales jusque-là restées dans l'ombre, en raison de préjugés tenaces : on a longtemps pensé que l'agriculteur n'avait guère à manier le crayon dans un métier qui se transmettait de père en fils et qui s'acquérait, pour l'essentiel, par imprégnation . Deux interrogations, en forme d'hypot..

Advanced survival models for risk-factor analysis in scrapie

Because of the confounding effects of long incubation duration and flock management, accurate epidemiological studies of scrapie outbreaks are difficult to carry out. In this study, 641 Manech red-faced sheep from six scrapie-affected field flocks in Pyrénées Atlantiques, France, were monitored for clinical scrapie over a 6–9 year period. Over this period, 170 scrapie clinical cases were recorded and half of the culled animals were submitted for post-mortem transmissible spongiform encephalopathy diagnosis to assess their infectious status. Collected data were analysed using a ‘mixture cure model’ approach, which allowed for the discriminating effect of PrP genotype and flock origin on incidence and incubation period. Simulations were performed to evaluate the applicability of such a statistical model to the collected data. As expected, ARR heterozygote sheep were less at risk of becoming infected than ARQ/ARQ individuals and had a greater age at clinical onset. Conversely, when compared with ARQ/ARQ, the VRQ haplotype was associated with an increased infection risk, but not a shorter incubation period. Considering the flock effect, we observed that a high incidence rate was not associated with shorter incubation periods and that the incubation period could be significantly different in flocks harbouring similar infection risks. These results strongly support the conclusion that other parameters, such as the nature of the agent or flock management, could interfere with epidemiological dynamics of the infection in scrapie-affected flocks

Development of a pig jejunal explant culture for studying the gastrointestinal toxicity of the mycotoxin deoxynivalenol: histopathological analysis

The digestive tract is a target for the mycotoxin deoxynivalenol (DON), a major cereals grain contaminant of public health concern in Europe and North America. Pig, the most sensitive species to DON toxicity, can be regarded as the most relevant animal model for studying the intestinal effects of DON. A pig jejunal explants culture was developed to assess short-term effects of DON. In a first step, jejunal explants from 9-13 week-old and from 4-5 week-old pigs were cultured in vitro for up to 8 hours. Explants from younger animals were better preserved after 8 hours, as assessed by morphological scores and by villi lengths. In a second step, dose-related alterations of the jejunal tissue were observed, including shortened and coalescent villi, lysis of enterocytes, oedema. After 4h of DON exposure of explants from 4-5 week-old pigs, a no-effect concentration level of 1 µM was estimated (corresponding to diet contaminated with 0.3 mg DON/kg) based on morphological scores, and of 0.2 µM based on villi lengths. In conclusion, our data indicate that pig intestinal explants represent a relevant and sensitive model to investigate the effects of food contaminants

Selection of alternative material for High velocity impact: Numerical and experimental validation of performance and weight saving

International audienceIn the scope of the future certification of engine powered aircraft, aircraft manufacturers should address and assume the event of engine burst, including the release/loss of fragments. To minimize the size of reinforcement area on the aircraft, ONERA and DLR have proposed to determine ballistic limit of potential alternative materials. The present document is the state of the common ONERA/DLR work performed in the European Project CLEANSKY 2, which aims to develop numerical tools and methodology for high velocity impacts using the explicit research code Europlexus as well as the commercial code Abaqus/Explicit. For that purpose, a comparison with experimental high velocity impact on different panels made with promising material has been performed

Eléments finis d'ordre élevé avec condensation de masse pour l'équation des ondes en dimension 1

Projet IDENTCe rapport est consacré à la construction et à l'analyse d'une méthode d'ordre élevé en espace et en temps pour résoudre l'équation des ondes en dimension 1. Cette méthode est fondée sur des éléments finis de Lagrange de type $P_1$, $P_2$ et $P_3$ avec condensation de masse, afin d'éviter une inversion de la matrice de masse à chaque pas de temps. Alors que pour $P_1$ et $P_2$ les éléments restent inchangés, la condensation de masse implique pour $P_3$ un déplacement des points intérieurs, afin qu'ils coïncident avec les points de quadrature de Gauss-Lobatto. Une analyse par Fourier de la méthode sur un maillage régulier met en évidence un résultat de superconvergence. Le gain de précision est illustré par des expériences numériques

Development of a pig jejunal explant culture for studying the gastrointestinal toxicity of the mycotoxin deoxynivalenol: Histopathological analysis. Toxicol

Abstract The digestive tract is a target for the mycotoxin deoxynivalenol (DON), a major cereals grain contaminant of public health concern in Europe and North America. Pig, the most sensitive species to DON toxicity, can be regarded as the most relevant animal model for studying the intestinal effects of DON. A pig jejunal explants culture was developed to assess short-term effects of DON. In a first step, jejunal explants from 9-13 week-old and from 4-5 week-old pigs were cultured in vitro for up to 8 hours. Explants from younger animals were better preserved after 8 hours, as assessed by morphological scores and by villi lengths. Dose-related alteration of the jejunal tissue were observed, including shortened and coalescent villi, lysis of enterocytes, oedema. A no-effect concentration level of 1 μM was estimated (corresponding to diet contaminated with 0.3 mg DON/kg) based on morphological scores, and of 0.2 μM based on villi lengths. In conclusion, our data indicate that pig intestinal explants represent a relevant and sensitive model to investigate the effects of food contaminants

Apoptosis, G1 Phase Stall, and Premature Differentiation Account for Low Chimeric Competence of Human and Rhesus Monkey Naive Pluripotent Stem Cells

After reprogramming to naive pluripotency, human pluripotent stem cells (PSCs) still exhibit very low ability to make interspecies chimeras. Whether this is because they are inherently devoid of the attributes of chimeric competency or because naive PSCs cannot colonize embryos from distant species remains to be elucidated. Here, we have used different types of mouse, human, and rhesus monkey naive PSCs and analyzed their ability to colonize rabbit and cynomolgus monkey embryos. Mouse embryonic stem cells (ESCs) remained mitotically active and efficiently colonized host embryos. In contrast, primate naive PSCs colonized host embryos with much lower efficiency. Unlike mouse ESCs, they slowed DNA replication after dissociation and, after injection into host embryos, they stalled in the G1 phase and differentiated prematurely, regardless of host species. We conclude that human and non-human primate naive PSCs do not efficiently make chimeras because they are inherently unfit to remain mitotically active during colonization