La formation du prix du riz : théorie et application au cas d'Antananarivo (Madagascar) .

A small intertemporal model of an asset market is analysed for explaining the determina­tion of the price of rice in Antananarivo (Madagascar). The gap between the price pre­vailing at the time of the harvest and that prevailing at the lean season is explained by the physical and financial costs of storage and by expectations errors The model is used for discussing various economic policy problems regarding the nee market and an econo metric application suggests that there is some inertia in the traders expectation forma tion It is shown as well that imperfect competition on this market increases the variability of the price and not its average levelUn petit modèle intertemporel de marché d'actif est analysé pour expliquer la formation du prix du riz à Antananarivo (Madagascar). L'écart entre le prix à la récolte et le prix à la soudure est expliqué par les coûts physiques et financiers du stockage, et par les erreurs de prévision. Le modèle est utilisé pour discuter divers problèmes de politique économique relative au marché du riz, et une application économétrique suggère une certaine inertie des prévisions des marchands. On montre aussi comment la concurrence imparfaite sur ce marché accroît la variabi­lité du prix, et non son niveau moyen.Azam Jean-Paul, Bonjean Catherine. La formation du prix du riz : théorie et application au cas d'Antananarivo (Madagascar) . In: Revue économique, volume 46, n°4, 1995. pp. 1145-1166

La formation du prix du riz : théorie et application au cas d'Antananarivo (Madagascar) .

[fre] Un petit modèle intertemporel de marché d'actif est analysé pour expliquer la formation du prix du riz à Antananarivo (Madagascar). L'écart entre le prix à la récolte et le prix à la soudure est expliqué par les coûts physiques et financiers du stockage, et par les erreurs de prévision. Le modèle est utilisé pour discuter divers problèmes de politique économique relative au marché du riz, et une application économétrique suggère une certaine inertie des prévisions des marchands. On montre aussi comment la concurrence imparfaite sur ce marché accroît la variabi­lité du prix, et non son niveau moyen. [eng] A small intertemporal model of an asset market is analysed for explaining the determina­tion of the price of rice in Antananarivo (Madagascar). The gap between the price pre­vailing at the time of the harvest and that prevailing at the lean season is explained by the physical and financial costs of storage and by expectations errors The model is used for discussing various economic policy problems regarding the nee market and an econo metric application suggests that there is some inertia in the traders expectation forma tion It is shown as well that imperfect competition on this market increases the variability of the price and not its average level

Replication of Systematic Reviews: Is It to the Benefit or Detriment of Methodological Quality?

International audienceOBJECTIVE: To perform an overview of the overlap of systematic reviews (SR) assessing direct oral anticoagulants (DOACs) and characterise these reviews in terms of bias and methodological quality (PROSPERO: CRD42022316273). STUDY DESIGN AND SETTING: A PubMed-indexed search was performed from inception to 31 January 2022 to identify SR evaluating DOACs in patients treated for an acute venous thromboembolism. The risk of bias of these SR was assessed according to the Risk Of Bias In Systematic reviews (ROBIS) tool. Redundancy was defined as overlap in terms of the type of population considered, the interventions compared and the studies included. RESULTS: A total of 144 SR were evaluated, of which 26 (18.1%) were classified as original, 87 (60.4%) as conceptual replications and 31 (21.5%) as excessive replications. The risk of bias was high in 19 (73.1%) of the original SR, 65 (74.7%) of the conceptual replications and 21 (67.7%) of the excessive replications. Compared to the original SR, the overall methodological quality was not improved in either conceptual or excessive replications. CONCLUSION: A large number of SR were classified as replications, a fifth constituted excessive replications. The replications showed no improvement in overall methodological quality compared to the original SR

Natural History and Treatment Strategies of Advanced PEComas: A Systematic Review

International audiencePEComas is a family of rare mesenchymal tumors. This systematic review aims to better understand the natural history of advanced PEComas. After a search on the PubMed database and main oncology meeting libraries according to the PRISMA guidelines, 88 articles reported in the English literature were included. Data on clinical and histological features, treatments and outcomes were collected. To identify risk factors, univariate and multivariate analyses were performed. Seven cohorts of patients and 124 individual patients were identified. Focusing on case reports, most patients were metastatic, and the median overall survival (OS) of the entire cohort was 60 months (95%CI 33; NA). Risk factors significantly associated with OS in the multivariate analysis were the presence of metastasis at diagnosis (HR: 2.59, 95%CI 1.06; 6.33, p = 0.036) and the grouped-Bleeker's risk category (HR: 4.66; 95%CI 1.07; 20.19; p = 0.039). In the metastatic population, only the presence of lymph node metastasis was associated with OS (HR: 3.11; 95%CI 1.13; 8.60, p < 0.05). Due to a lack of events, it was not possible to conclude on other factors. This review of the literature highlights the heterogeneity of literature data and shows the great diversity of clinical management strategies

Laminin and 67 Kd Laminin Binding Protein in Mouse B16 Melanoma Cells and 3t3 Fibroblast Spheroids

Multicellular spheroids which promote cell-cell and cell-matrix interactions were prepared in culture with mouse B16 melanoma cells (pigmented or non pigmented) alone or mixed with mouse 3T3 fibroblasts. Their volume and proliferation or necrosis rate were evaluated. As measured by dot blot immunoassay, laminin was mainly produced by fibroblasts rather than by melanoma cells. High levels of laminin B1 chain mRNA were detected only in spheroids composed of 3T3 fibroblasts. The levels of 67 kD laminin binding protein mRNA were high in all cell populations studied here

A COVID-19 European data set to support training in pandemic management

The PANDEM-2 COVID-19 European training dataset is a large collection of time series associated with indicators on the European pandemic response to the COVID-19 pandemic. It is intended to be used for training in pandemic management. This dataset is the result of a data gathering requirement process for pandemic management involving feedback and inputs from several public health and first responder professionals as well as researchers directly involved in the European COVID-19 pandemic response. This work is part of the PANDEM-2 project funded by the Horizon 2020 Secure Societies program. To collect this data, an open source software was developed named PANDEM-Source allowing reproducibility and customisation of this dataset. The dataset includes indicators for cases, deaths, hospitalisation, testing and laboratory data including pathogen genomic information, vaccination, non-pharmaceutical interventions, participatory surveillance, social media, human and material resources, flights and contact tracing activities. When no open available data was found, realistic synthetic data and indicators were generated with the goal of producing a data set to be used for pandemic management training

Influence of laminin or fibroblasts upon colony formation in the mouse by B16 melanoma cell spheroids: a morphometric analysis.

peer reviewedBy microscopical observation and using an original morphometric method, we analyzed on histological sections the rate of lung colony formation after the intravenous injection into the mouse of B16 melanoma cells previously cultivated in vitro as aggregates. After the injection of B16 pure spheroids, superficial lung colonies were more numerous than internal lung colonies. After the injection of mixed spheroids (B16 + 3T3 fibroblasts), the size of colony sections was increased. Addition of laminin to pure or mixed spheroids decreased the size of colony sections but increased the number of internal lung colonies