A(40)Ar/(39) Ar study of oceanic and continental deformation processes during an oblique collision: Taconian orogeny in the Quebec reentrant of the Canadian Appalachians

International audienceTwo phases of penetrative deformation are documented in the Taconian hinterland of the Appalachian orogen in the Gaspé Peninsula. D1 is associated with the obduction of the Mont-Albert ophiolite onto the Paleozoic Laurentian margin, whereas D2 corresponds to later transport of allochthons across the margin. In the metamorphic sole, S1 is a SE-dipping mylonitic fabric with a downdip lineation. In underlying metabasalts, D1 is characterized by NW-overturned and recumbent folds, and a subhorizontal S1 schistosity with an ENE-trending orogen-parallel lineation. D2 is characterized by a S2 steeply dipping penetrative axial-planar crenulation cleavage and NE-trending F2 folds. The intraoceanic thrusting of ophiolite is dated at 465 Ma (early D1) whereas emplacement of ophiolite and subsequent deformation of the margin was recorded by isotopic signatures between 459 and 456 Ma (late D1). D2 is dated at 448 Ma throughout the hinterland. Taconian transpressive deformation is related to an oblique collision within the Quebec reentrant of the Canadian Appalachians during the Ordovician

Incorporation de particules de bardeaux d’asphalte de postconsommation dans les enrobés bitumineux

Annuellement, au Québec, plus de 200 000 tonnes de bardeaux d’asphalte usés provenant des toitures résidentielles sont envoyées dans des sites d’enfouissement de matériaux secs. Dans le but de réduire cette grande quantité de déchets, un projet de recherche financé par le 3RMCDQ et RECYC-QUÉBEC est en cours au LCMB visant à déterminer la faisabilité d’incorporer des particules de bardeaux d’asphalte de postconsommation dans des enrobés bitumineux pouvant être utilisés sur les routes québécoises. Présentement, le ministère des Transports du Québec (MTQ) accepte de substituer 5 % de la masse granulaire des enrobés par des particules de bardeaux d’asphalte de postfabrication (rejet d’usine) dans les enrobés de base et jusqu’à 3 % pour les enrobés de surface. L’incorporation des particules de bardeaux de postfabrication est valorisée notamment par la normalisation du MTQ d’un taux de réduction de la teneur en bitume d’apport de ces enrobés. Actuellement, l’incorporation des particules dites de postconsommation n’est pas encore régularisée par le MTQ, mais fait l’objet de planches expérimentales. Les recherches en cours au LCMB visent à cerner les performances d’un enrobé de base de type GB-20 et d’un enrobé de surface de type ESG-10 incorporant des particules de bardeaux d’asphalte de postconsommation. Des enrobés contenant différents dosages de bitume d’apport ont été étudiés pour évaluer l’effet sur l’aptitude au compactage, sur la résistance à l’orniérage, sur la résistance aux basses températures (TSRST) et sur le module complexe (E*). Les différents dosages en bitume sont basés sur différents apports théoriques en bitume des particules des bardeaux. Cette étude a permis de cibler une formulation optimale pour les deux types d’enrobé bitumineux testés. Les résultats montrent que pour les enrobés de type ESG-10, l’apport envisageable du bitume des bardeaux d’asphalte de postconsommation serait de l’ordre de 20 % alors que dans le cas des enrobés de type GB-20, aucune réduction de la teneur en bitume d’ajout ne peut être envisagée pour le moment lorsque 5 % de particules de bardeaux sont incorporées à la formulation de l’enrobé. Dans ce cas-ci, des essais supplémentaires de modules complexes sont recommandées afin d’obtenir des résultats significatifs qui permettront de déterminer si une réduction de la teneur en bitume d’ajout ne serait pas favorable

When a collective outcome triggers a rare individual event: a mode of metastatic process in a cell population

A model of early metastatic process is based on the role of the protein PAI-1, which at high enough extracellular concentration promotes the transition of cancer cells to a state prone to migration. This transition is described at the single cell level as a bi-stable switch associated with a subcritical bifurcation. In a multilevel reaction-diffusion scenario, the microenvironment of the tumor is modified by the proliferating cell population so as to push the concentration of PAI-1 above the bifurcation threshold. The formulation in terms of partial differential equations fails to capture spatio-temporal heterogeneity. Cellular-automata and agent-based simulations of cell populations support the hypothesis that a randomly localized accumulation of PAI-1 can arise and trigger the escape of a few isolated cells. Far away from the primary tumor, these cells experience a reverse transition back to a proliferative state and could generate a secondary tumor. The proposed role of PAI-1 in controlling this metastatic cycle is candidate to explain its role in the progression of cancer

Human pregnancy complicated by Chlamydia psittaci acquired from goat, a new zaonotic infection ?

Nous rapportons le cas d’une femme dont la grossesse s’est spontané ment interrompue à 32 semaines d’aménorrhée en raison d’une infection très sévère par Chlamydia psittaci. Cette infection est secondaire à un contact avec un troupeau de chèvres. Neuf cas d’infection materno-fœtale par Chlamydia psittaci d’origine animale sont décrits dans la littérature, il s’agit toujours d’une contamination par les brebis atteintes de chlamydiose abortive. La chèvre peut également être infectée par ce germe, mais la trans mission à la femme enceinte de la chlamydiose abortive caprine n’a pas été décrit jusqu’à présent.A case of chlamydial infection in pregnant woman is described. This infection was contracted from goat. The woman, who had contact with caprine abortion, spontaneously delivered a stillborn infant in the 32nd week of pregnancy. She developed dessiminated intravascular coagulation post partum with acute renal failure and pulmonary oedema. Nine cases of chlamydial infections in pregnant women have been reported in literature, in all cases, the infection was contracted from ewes suffering from enzootic abortion. Such an infection acquired from goat have not been previously described

Biomodélisation / Biological modelling Modéliser les interactions moléculaires par la théorie des réseaux de jeux

Abstract Modelling molecular interactions with game networks' theory. We present a method to model biological systems, the theory of games networks. It extends game theory by multiplying the number of games, and by allowing agents to play several games simultaneously. Some important notions of biological systems, such as locality of interactions and modularity, can then be modelled. Abridged English version Introduction The study of molecular networks by 'high-throughput' techniques is based on coupling in-silico modelling and experimental validation. This interdisciplinary ap-* Auteur correspondant. Adresse e-mail : [email protected] (F. Delaplace). proach leads us to revisit the model-experimentation cycle by integrating computing for the formulation of assumptions. The interaction, resulting from the need to treat automatically a large amount of biological data, gives rise to new problems focused on the conception of computational frameworks for biological modelling. Hence, the question is to correctly interpret data by these formal models, in accordance with methods, biological observations, and possible therapeutic applications. The interpretation may lead to a better under-1631-0691/$ -see front matte

New methods to spatially extend thermal response test assessments

Thermal response tests (TRTs), used to evaluate the subsurface thermal conductivity when designing ground source heat pump systems, are spatially limited to the vicinity of the borehole where a test is carried out. The subsurface is heterogeneous and the thermal conductivity assessment provided by a TRT is likely to vary beyond the tested borehole. New methods have, therefore, been developed to extend subsurface assessments at the building site and the urban district scales. The first method relies on temperature profiles measured at equilibrium in ground heat exchangers that are reproduced with inverse numerical simulations to infer the terrestrial heat flow and the subsurface thermal conductivity beyond a first TRT. Inversion of temperature profiles was verified at a pilot site in the Appalachians where TRTs had been performed and showed a thermal conductivity estimate within less than 10 % for both approaches. The second method is based on geostatistical simulations to map the distribution of the subsurface thermal conductivity in areas where several ground source heat pump installations are anticipated. A first mapping exercise was achieved to the north of Montreal in the St. Lawrence Lowlands with fours TRTs and ten laboratory measurements interpolated with sequential Gaussian simulations

Long-term soil warming decreases microbial phosphorus utilization by increasing abiotic phosphorus sorption and phosphorus losses

Phosphorus (P) is an essential and often limiting element that could play a crucial role in terrestrial ecosystem responses to climate warming. However, it has yet remained unclear how different P cycling processes are affected by warming. Here we investigate the response of soil P pools and P cycling processes in a mountain forest after 14 years of soil warming (+4 °C). Long-term warming decreased soil total P pools, likely due to higher outputs of P from soils by increasing net plant P uptake and downward transportation of colloidal and particulate P. Warming increased the sorption strength to more recalcitrant soil P fractions (absorbed to iron oxyhydroxides and clays), thereby further reducing bioavailable P in soil solution. As a response, soil microbes enhanced the production of acid phosphatase, though this was not sufficient to avoid decreases of soil bioavailable P and microbial biomass P (and biotic phosphate immobilization). This study therefore highlights how long-term soil warming triggers changes in biotic and abiotic soil P pools and processes, which can potentially aggravate the P constraints of the trees and soil microbes and thereby negatively affect the C sequestration potential of these forests

Long-term soil warming decreases microbial phosphorus utilization by increasing abiotic phosphorus sorption and phosphorus losses

Phosphorus (P) is an essential and often limiting element that could play a crucial role in terrestrial ecosystem responses to climate warming. However, it has yet remained unclear how different P cycling processes are affected by warming. Here we investigate the response of soil P pools and P cycling processes in a mountain forest after 14 years of soil warming (+4 °C). Long-term warming decreased soil total P pools, likely due to higher outputs of P from soils by increasing net plant P uptake and downward transportation of colloidal and particulate P. Warming increased the sorption strength to more recalcitrant soil P fractions (absorbed to iron oxyhydroxides and clays), thereby further reducing bioavailable P in soil solution. As a response, soil microbes enhanced the production of acid phosphatase, though this was not sufficient to avoid decreases of soil bioavailable P and microbial biomass P (and biotic phosphate immobilization). This study therefore highlights how long-term soil warming triggers changes in biotic and abiotic soil P pools and processes, which can potentially aggravate the P constraints of the trees and soil microbes and thereby negatively affect the C sequestration potential of these forests

Acercamiento a la familia Maceo-Grajales desde la óptica martiana

Introduction:Maceo-Grajales family is recognized in national history for their dedication to the struggle for the independence of Cuba and for the lead role in important episodes of patriotism, humanism, discipline and morality. Objective:to describe Maceo-Grajales family from the perspective of Jose Marti ideas. Method:a historical research based on the materialist-dialectical method was carried out. Analysis-synthesis, induction-deduction and historical-logical theoretical methods were used. At the empirical level, a documentary analysis of 16 bibliographic articles from different databases was carried out from December 2017 to February 2018. Conclusions:from the perspective of the Apostle, the high revolutionary intransigence, patriotism and courage inculcated in Maceo family, allowed to bring about capable liberators of sacrificing their lives to achieve a free Cuba.Introducción: la familia Maceo-Grajales es reconocida en la historia nacional por su consagración a la lucha por la independencia de Cuba y por protagonizar importantes episodios de patriotismo, humanismo, disciplina y moral.Objetivo: describir la familia Maceo–Grajales desde la óptica martiana.Método: se realizó una investigación histórica sustentada en el método materialista-dialéctico. Dentro del nivel teórico se emplearon métodos como el de análisis-síntesis, inducción-deducción e histórico-lógico. En el nivel empírico se realizó el análisis documental de 16 artículos bibliográficos procedentes de diferentes bases de datos, en el periodo de diciembre de 2017 a febrero de 2018.Conclusiones: desde la óptica del Apóstol, la elevada intransigencia revolucionaria, el patriotismo y la valentía inculcada en el seno familiar de los Maceo, permitió formar libertadores capaces de sacrificar su vida para lograr una Cuba libre