3,382 research outputs found
Comptabilité marchande et crédit au XVIIIe siÚcle : étude d'une relation d'affaires de la maison nantaise Chaurand frÚres
Lâanalyse dâune relation dâaffaires, de plus dâune dizaine dâannĂ©es, entre deux grandes maisons de nĂ©goce de Nantes et de Bordeaux, Ă partir du compte courant ouvert Ă la seconde par la premiĂšre, permet dâapprĂ©hender de maniĂšre approfondie le rĂŽle jouĂ© par la comptabilitĂ© dans les pratiques du crĂ©dit marchand et dans lâarticulation monnaie scripturale â monnaie fiduciaire.La comptabilitĂ© est lâun des artefacts essentiels Ă la mise Ćuvre du crĂ©dit. Inscription du crĂ©dit et moyen de preuve de son existence, elle est aussi instrument de crĂ©dit et moyen de paiement. Le compte courant ouvert Ă un partenaire rend compte de façon continue du crĂ©dit accordĂ© Ă (ou par) ce partenaire et des compensations qui sâopĂšrent au fur et Ă mesure des livraisons rĂ©ciproques. Il est de ce fait le siĂšge du rĂšglement scriptural, le jeu dâĂ©critures rĂ©alisant le paiement dâune dette par une crĂ©ance. Mais la comptabilitĂ© permet aussi dâassurer le suivi des titres de crĂ©dit Ă©mis ou reçus : la monnaie fiduciaire ; le tout en liaison avec les diverses opĂ©rations rĂ©alisĂ©es.Cette Ă©tude micro-historique en livre une illustration qui, au-delĂ des caractĂ©ristiques propres Ă cette relation â nature et rythmes des Ă©changes et donc du crĂ©dit â, conduit Ă des observations de portĂ©e plus gĂ©nĂ©rale relativement au crĂ©dit marchand. Elle met Ă©galement en lumiĂšre le rĂŽle de la comptabilitĂ© dans la construction et la pĂ©rennisation de la relation de crĂ©dit : lâartefact comptable nâest pas que le tĂ©moin passif de cette relation, il en est acteur par le biais des rituels de redditions de comptes. NĂ©e de la pratique du crĂ©dit marchand, la comptabilitĂ© a directement participĂ© Ă son expansion
COMPUTATIONAL MODELLING OF HUMAN AESTHETIC PREFERENCES IN THE VISUAL DOMAIN: A BRAIN-INSPIRED APPROACH
Following the rise of neuroaesthetics as a research domain, computational aesthetics has also known a regain in popularity over the past decade with many works using novel computer vision and machine learning techniques to evaluate the aesthetic value of visual information. This thesis presents a new approach where low-level features inspired from the human visual system are extracted from images to train a machine learning-based system to classify visual information depending on its aesthetics, regardless of the type of visual media. Extensive tests are developed to highlight strengths and weaknesses of such low-level features while establishing good practices in the domain of study of computational aesthetics. The aesthetic classification system is not only tested on the most widely used dataset of photographs, called AVA, on which it is trained initially, but also on other photographic datasets to evaluate the robustness of the learnt aesthetic preferences over other rating communities.
The system is then assessed in terms of aesthetic classification on other types of visual media to investigate whether the learnt aesthetic preferences represent photography rules or more general aesthetic rules. The skill transfer from aesthetic classification of photos to videos demonstrates a satisfying correct classification rate of videos without any prior training on the test set created by Tzelepis et al. Moreover, the initial photograph classifier can also be used on feature films to investigate the classifierâs learnt visual preferences, due to films providing a large number of frames easily labellable. The study on aesthetic classification of videos concludes with a case study on the work by an online content creator. The classifier recognised a significantly greater percentage of aesthetically high frames in videos filmed in studios than on-the-go. The results obtained across datasets containing videos of diverse natures manifest the extent of the systemâs aesthetic knowledge.
To conclude, the evolution of low-level visual features is studied in popular culture such as in paintings and brand logos. The work attempts to link aesthetic preferences during contemplation tasks such as aesthetic rating of photographs with preferred low-level visual features in art creation. It questions whether favoured visual features usage varies over the life of a painter, implicitly showing a relationship with artistic expertise. Findings display significant changes in use of universally preferred features over influential
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abstract paintersâ careers such an increase in cardinal lines and the colour blue; changes that were not observed in landscape painters. Regarding brand logos, only a few features evolved in a significant manner, most of them being colour-related features.
Despite the incredible amount of data available online, phenomena developing over an entire life are still complicated to study. These computational experiments show that simple approaches focusing on the fundamentals instead of high-level measures allow to analyse artistsâ visual preferences, as well as extract a communityâs visual preferences from photos or videos while limiting impact from cultural and personal experiences
Finite size effects in a model for plasticity of amorphous composites
We discuss the plastic behavior of an amorphous matrix reinforced by hard
particles. A mesoscopic depinning-like model accounting for Eshelby elastic
interactions is implemented. Only the effect of a plastic disorder is
considered. Numerical results show a complex size-dependence of the effective
flow stress of the amorphous composite. In particular the departure from the
mixing law shows opposite trends associated to the competing effects of the
matrix and the reinforcing particles respectively. The reinforcing mechanisms
and their effects on localization are discussed. Plastic strain is shown to
gradually concentrate on the weakest band of the system. This correlation of
the plastic behavior with the material structure is used to design a simple
analytical model. The latter nicely captures reinforcement size effects in
observed numerically. Predictions of the effective flow
stress accounting for further logarithmic corrections show a very good
agreement with numerical results.Comment: 18 pages, 19 figure
IdĂ©ologies et comptabilitĂ©: lâexemple français de lâuniformisation des mĂ©thodes de calcul de coĂ»ts.1927-1947. (Ideologies and Accounting: the French Case of Standardization of Cost Finding Methods. 1927-1947).
Basado en un estudio detallado de la literatura tĂ©cnica de la Ă©poca, asĂ como en detenidas investigaciones archivĂsticas, este artĂculo establece una relaciĂłn entre las tentativas privadas de normalizaciĂłn de los mĂ©todos del cĂĄlculo de costes, realizadas en Francia entre las dos guerras mundiales, y algunas ideologĂas propias de ese perĂodo. This paper is based on a detailed study of the technical literature of the day as well as on thorough research in the archives. It aims to identify a relationship between the private standardization attempts of cost finding methods carried out in France between the two world wars and some ideologies of this period.Contabilidad de gestiĂłn, corporativismo, secciones homogĂ©neas, tecnocracia. Corporativism, management accounting, sections homogĂšnes, tecnocracy.
The Early Local and Regional Immune Response to Recall Inoculations of Mycobacterium Leprae in the Skin of Rhesus Macaques (Macaca Mulatta).
Epidemiological studies have failed to show any important impact of human immunodeficiency virus (HIV) infection and disease on leprosy, in contrast to the well documented increase in incidence and morbidity with other mycobacteria in these patients, notably Mycobacterium tuberculosis. The early events following exposure and repeated exposure to Mycobacterium leprae (ML) have not still been studied. Previous studies of first inoculations of ML in the skin of rhesus monkeys have indicated delayed recruitment of CD4+ cells and delayed interleukin (IL) 2 secretion in skin inoculation sites in simian immunodeficiency (SIV) positive animals. The development of the secondary immune response against a challenge of ML was studied over a period of 2 months in the skin of 9 rhesus macaques, all inoculated previously with ML, 3 of which were SIV positive slow progressors. Cell recruitment and types of cytokine response in the skin and draining lymph nodes (LN) were investigated using flow cytometry (FC), immunohistochemistry, and reverse transcription polymerase chain reaction to detect relative levels of messenger ribonucleic acid (mRNA) expression for IL2, IL4, interferon gamma (IFNgamma) and IL10. Results were analyzed according to SIV status and persistence of ML infection. An early vigorous expression of IL2 and IFNgamma mRNA, indicative of a strong T helper (Th) 1 cytokine profile, was seen in the skin of macaques that cleared ML infection. Animals that developed persistent ML infection (ML+) had delayed, weak Th1 response, and no evidence of early Th2 response in the skin. In contrast, early up regulation of IL4 was only observed in the LN of ML+ macaques. Recruitment of CD4+ lymphocytes into the skin was significantly lower and delayed in ML+ animals. CD4:CD8 ratio were significantly lower in the blood in SIV+ monkeys. However, no significant differences in CD4+ lymphocyte recruitment or expression of cytokine mRNA were observed between SIV- and SIV+ monkeys. Despite evidence of systemic immunodepression, the slow progressing SIV+ rhesus macaques are still capable of mounting an adequate response to ML re-inoculation in the skin. A Th2 response is not generated in the skin early after re-infection in animals which developed progressive infection
Indices of Exposure to Polycyclic Aromatic Hydrocarbons in a Bioindicator Species: Point Mutation Detection in the Cotton Rat.
Release of energy-related contaminants occurs ubiquitously in the environment. Cancer induction by polycyclic aromatic hydrocarbons (PAHs) and aromatic amines have been well recognized in the workplace and are also suspected among the general population. Environmental PAHs exposure and effects have been investigated using biomarkers in aquatic and, to a lesser extent, terrestrial animals. Attempts to monitor the presence and effects of PAHs through the detection of point mutations in genes involved in carcinogenesis (p53 and K-ras) would yield interesting clues regarding possible etiologic agents and their potential effect. The identification of a mutation type, known to be GâT transversion predominantly with PAHs and aromatic amines, would be indicative of these families of chemicals, while their presence in a tumor suppressor gene and an oncogene represents additional molecular hits with potential biological significance. Achievement of this goal requires the development of Polymerase Chain Reaction/Restriction Enzyme/Ligase Chain Reaction assays which are able to detect and identify rare mutations in non-neoplastic tissues with sensitivities greater than 10--6 for various genomic sites in humans. Cotton rats (Sigmodon hispidus) appeared to be a good candidate bioindicator. Inbred Cotton rats were used to assess the sensitivity of this species to the toxic effects of PAHs using benz[a]anthracene (BaA) and 2-aminoanthracene (2AA). Although Cotton rats appeared to have the metabolic capabilities to yield reactive diol epoxide and aromatic nitrenium. intermediates, their response to the toxic effects of BaA was not obvious after two weeks per os exposure as compared to F344 rats based on their food intake. 2AA toxicity and carcinogenicity were also reduced in Cotton rats compared to F344 rats following per os and intraperitoneal exposure as assessed by the absence of decrease in food intake and in weight gain, and the non-occurrence of preneoplastic and neoplastic lesions. However, the adaptation of the mutation detection assay to the selected species did not yield the desired sensitivity secondary to primer misalignment and polymerase fidelity error. These results highlight the risk inherent in extrapolation from one species to another and suggest that Cotton rats may not be a sensitive bioindicator of PAHs exposure
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