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In 2017, Quebec’s Auditor General reported several major issues regarding government-funded French as a second language (FSL) courses, especially those intended for adult students with limited or interrupted formal education (SLIFE). To this day, no official framework or program exists for this specific population, a situation that the government of Quebec wishes to resolve. Our research team was thereby mandated by the Ministry of Immigration to conduct a large-scale multilingual study with the objective of gaining a better understanding of the realities and needs of the various stakeholders involved in low-literate FSL classes. We met 42 teachers, 24 French learning center directors, and 10 pedagogical advisors in individual interviews; we also led 107 group interviews with SLIFE in 26 languages, allowing us to meet 464 adult SLIFE enrolled in low-literate FSL classes from 11 regions of the province of Quebec, most of them being refugees. This article reports on the decision-making process in which we engaged to overcome the ethical and methodological challenges we faced at various stages of the data collection with SLIFE participants: recruitment, informed consent, confidentiality, interview protocol design, instrument piloting, data collection, and data translation and transcription. To make informed decisions, we had to turn to literature outside SLA (i.e., refugee research and translation/interpreting literature) for guidance. In this article we discuss the limitations and contributions of our research to guide researchers who will conduct studies with similar non-academic samples/populations.

The COVID-19 pandemic has affected many in-person laboratory courses across the world. The viral spreading model is complicated but parameters, such as its reproduction number, Rt, can be estimated with the susceptible, infectious, or recovered (SIR) model. COVID-19 data for many states and countries are widely available online. This provides an opportunity for the students to analyze its spreading kinetics remotely. Here, we reported a lab carried out online during the third week of the spring semester of 2021 to minimize social contacts. Due to the wide interest in developing online physical chemistry and analytical labs during the pandemic, we’d like to share this lab design. The method, technique, procedure, and grading are described in this report. The student participants were able to apply the kinetic techniques learned in physical chemistry to successfully analyze an ongoing real-world problem through a remote learning environment and prepare this report.

International audience; Mediterranean temporary pools are threatened ecosystems that host a unique plant community, mostly composed of annual species with large and long-lived seed banks. The longevity of their seed bank, the scarcity of their habitat, the small size of their populations and the low frequency of above-ground vegetation result in a low probability of detection of these species. The discovery of new populations of such rare species are thus important for our understanding of the ecology of the temporary pool ecosystem. Lythrum thesioides M.Bieb., 1808 is a very rare annual species of temporary pools and river banks which was thought to be extinct in the South of France until 1998. Here, we review the distribution of the species and report the recent discovery of a population during a targeted search combining historical data on wetland occurrence on a particular geological substrate. We present new information on its autecology, pollen morphology and the karyotype. Only three populations are currently known worldwide for Lythrum thesioides, and only one of these has favorable management conditions. Thus, we outline new conservation perspectives in the context of a targeted search project and the conservation management of one population.

The goal of the study was to evaluate the effect of the machining conditions on the sulfide stress cracking (SSC) resistance of carbon steel. The paper presents the results obtained on two different carbon steel grades machined in conditions generating different surface residual stresses and correlates the stress state with the SSC resistance determined according to NACE TM0177 method A.

Resume Nous rapportons le suivi sur plusieurs annees d’un enfant IMC au langage d’apparence deviant. Le pronostic a ete radicalement modifie lorsque, en equipe, il a ete possible de soulever une hypothese physiopathologique mettant en cause les consequences d’un trouble de la motricite intrabuccale sur le developpement cognitif et, en particulier, celui de la reconnaissance de phonemes bien differencies. Ce type de presentation de deviance du langage n’est pas decrit comme tel dans la litterature sur le langage de l’enfant ; la terminologie que nous avons retenue pour l’expliciter au decours d’une evolution totalement resolutive, est celle de « trouble de l’integration phonetique ». Nous avancons une optique d’observation collegiale dynamique, dont l’interactivite a evite de figer le diagnostic dans un tableau trop vaste de « retard mental » ou « syndrome dysharmonique » evoque chez ce jeune enfant IMC. Cette approche nous a ouvert l’esprit a un mode d’expression du trouble moteur, le plus souvent probablement vite gomme par les stimulations d’un environnement habituel et qui est une forme de trouble de l’integration sensorielle. Il nous parait important de ne pas oublier que l’atteinte motrice peut aboutir, dans certaines circonstances, a empecher l’enfant de decrypter des informations capitales pour sa comprehension du monde environnant.

The fatigue resistance of car components such as crankshafts or diesel injection rails is mainly related to fatigue at geometrical singularities. Its understanding requires the simulations of the different steps of the industrial process resulting in residual stresses generation and their evolutions in service. First concerning crankshaft fatigue damage, a complete analytical model of residual stresses generation and shakedown in fatigue is presented. Then a fatigue criterion is established and validated for this application. Finally, for the high pressure diesel injection rail, this approach can be generalized to the holes intersection singularities.

The GFAC (French Association for residual stress analysis) decided in 2007 to work on external reference samples for residual stress analysis by X-ray diffraction as defined in the XPA 09-285 and EN 15305-2009 standards. Seven materials are studied: ferritic steel, martensitic steel, aluminium alloy, titanium alloy, 2 types of Nickel-Chromium alloy and tungsten thin layers deposited on silicon wafers. The purpose of this external round robin campaign is threefold: (i) to give possibilities for each laboratory involved in the campaign test to obtain external reference samples for each material tested, (ii) to validate a common procedure for qualification of external samples and (iii) to commercialise validated external reference samples through the GFAC association. A common approach of X-Ray diffraction parameters, samples geometry and standard procedure has been chosen and adopted by each laboratory involved in these tests. No indication in terms of residual stress calculation method is given; the choice of the method (centroid, middle point, maximum of peak, fitting…) is the choice of the laboratory according to their X-ray diffraction set-ups, softwares and experience. Once all samples are analysed, values given by each laboratory are compared and analysed.

ASCOMETAL produces alloy steels used for spring (leaf or coil), where the weak fatigue points are on the surface which is reinforced by shot-peening. So, the fatigue optimization with the steel grade needs a perfect knowledge of the material answer after shot-peening. For that reason, an analytical model has been developed where low cycle fatigue behaviour and all the usual process parameters are integrated (especially the impact position, and the covering-rate). Moreover, through a Monte-Carlos approach, the model permits to analyse the effect of scattering elements like impact speeds, ball sizes, or material fatigue behaviour. With this model several key process parameters have been analysed and validated with residual stress profiles evaluated by X-ray diffraction. So, for spring leaf, the effect of an applied load during shot-peening or shakedown during bending fatigue is described.

Cultural theory maintains that four worldviews—egalitarianism, individualism, hierarchicalism, and fatalism—can be used to describe people and societies. We examine survey measures of two of those worldviews—egalitarianism and individualism—to understand their relationship with belief systems. Contrary to what one might expect based on the cultural theory literature, we find that people with low levels of political knowledge seem not to have coherent worldviews regarding these issues. In contrast, people with high levels of political knowledge respond to egalitarianism and individualism questions as if they were opposite ends of a single, liberal-conservative continuum, rather than two of four distinct worldviews. We conclude that cultural theory researchers should take account of the influence of political knowledge whenever they investigate worldviews.

Variation in the lengths of restriction fragments (RFLPs) of the whole chloroplast DNA molecule was studied in 174 populations of Quercus ilex L. sampled over the entire distribution of this evergreen and mainly Mediterranean oak species. By using five endonucleases, 323 distinct fragments were obtained. From the 29 and 17 cpDNA changes identified as site and length mutations, respectively, 25 distinct chlorotypes were distinguished, mapped and treated cladistically with a parsimony analysis, using as an outgroup Q. alnifolia Poech, a closely related evergreen oak species endemic to Cyprus where Q. ilex does not grow. The predominant role of Q. ilex as maternal parent in hybridization with other species was reflected by the occurrence of a single very specific lineage of related chlorotypes, the most ancestral and recent ones being located in the southeastern and in the northwestern parts of the species’ geographical distribution, respectively. The lineage was constituted of two clusters of chlorotypes observed in the ‘ilex’ morphotyped populations of the Balkan and Italian Peninsulas (including the contiguous French Riviera), respectively. A third cluster was divided into two subclusters identified in the ‘rotundifolia’ morphotyped populations of North Africa, and of Iberia and the adjacent French regions, respectively. Postglacial colonization probably started from three distinct southerly refugia located in each of the three European peninsulas, and a contact area between the Italian and the Iberian migration routes was identified in the Rhone valley (France). Chlorotypes identical or related to those of the Iberian cluster were identified in the populations from Catalonia and the French Languedoc region, which showed intermediate morphotypes, and in the French Atlantic populations which possessed the ‘ilex’ morphotype, suggesting the occurrence of adaptive morphological changes in the northern part of the species’ distribution.

Nimbyism (‘Not in My Backyard’ opinions) and environmentalism are distinct concepts, but are easily confounded in practice. Do people object to proposed developments because they are environmentalists or because the developments are too close to where they live? This question is addressed using data from two public opinion surveys of Californians regarding their attitudes toward oil drilling. Our surveys allow examination of both environmentalism and Nimby effects among people who live within view of offshore oil platforms, among people who live in the same region, and among people who live quite far away. We find strong evidence that environmentalism influences attitudes, but no evidence of nimbyism – despite the fact that many respondents live in an area that is reputed to be a centre of anti-oil, Nimby behaviour. This suggests that nimbyism might be a pattern of political activism, rather than of public opinion.

International audience; A new species of Orobanche was discovered in the Calanques National Park near Marseille, where it seems to be endemic. Its exclusive host, Staehelina dubia (Asteraceae), was never mentioned before as a host for Orobanchaceae. The new species is described here and named Orobanche staehelinae. The diagnostic characters are given in comparison with possible related species (O. kochii, O. leptantha, O. loscosii, O. canescens and O. santolinae). Its peculiar ecology (thermophilous screes, habitat of community interest) and conservation status (endangered, IUCN red list category) are presented.

In the new types of diesel motors, the crankshaft loads increase dramatically. For that reason, to satisfy the requirements and needs of its motorist’s customers, ASCOMETAL has developed a special bending fatigue test applied to “Baldwin” specimens reinforced by deep rolling. Such test is representative of the main in-service loads existing in crankshaft crankpin fillets (one of the weakest point of the component). Thus, using this test, the mechanisms leading to the increase of the fatigue resistance brought by the deep rolling treatment, could be identified. This reinforcement is mainly linked to crack arrest due to both a decrease of the in-depth stress concentration factor and to remaining compressive residual stresses induced by the deep rolling. In this paper, the experimental methods (in particular X-rays diffraction) used to characterize the stress fields generated by the deep rolling treatment are described first. The equations of equilibrium and compatibility of the particular toric symmetry of the crankshaft crankpin fillets have been used then to analyze the surface and in-depth stress profiles of the tested sample. This allowed characterizing the shake down and stress relaxation induced by fatigue. The crack propagation behaviour and the associated fracture limits were also defined.

The dimensions and quality of forged-steel components are significantly affected by the action of friction and wear. The thermal and mechanical operating conditions of hot forging tools provoke serious degradation, such as oxidative wear, thermal fatigue, plastic damage and mechanical cracking. This slowly causes the tools to lose their original geometry and thus they must be either reformed or discarded [1]. The knowledge and control of this damage is essential and must be taken into consideration, both in die design and in the choice of tool material and the type of surface conditioning. The degradation has direct effects on the lifespan of the tools, and consequently on the cost of the components. This paper deals with the sliding wear behaviour of 40CrMoV13 Steel against C35E in the 700 to 850 °C temperature range under ambient conditions. This steel is used frequently as hot forging die material. This study focuses on the effect of the test temperature and the role of the oxide scales. The purpose of these experiments was to obtain tribological data (friction coefficient, wear rate, etc.), in order to include it in numerical simulations of damage to hot forging tools for the purpose of optimizing the tools' lifespan.

The non-destructive X-ray diffraction method is used to analyse carbo-nitrided steel layers after wear testing. These measurements are carried out on the two major phases of the material,i.e.the martensite and the retained austenite. Such measurements are particularly difficult for three reasons. First, strong gradients exist across the wear track. Second, the diffraction peaks obtained for the martensite are broadened, as a result of the overlap of different reflections of the tetragonal structure. Third, the studied material is multiphase. Its major phases are martensite and austenite, but it also contains carbide and nitride clusters, which lead to incoherent scattering of X-rays. A new quantitative phase analysis method is thus proposed to define the volume fractions of these different constituents of the material. This method accounts for the evolution of the background level during wear. A micro-mechanical model is then developed to process the diffraction peak positions obtained for the martensite and the retained austenite. This model defines the `true' stress and carbon content of both phases. It also allows separation of the reflections of the martensite. The true widths of the diffraction peaks, which characterize the plastic deformation, can thus be quantified. Results for wear-test specimens show a strong plastic deformation of the retained austenite during contact fatigue. This leads to a partial transformation of this phase into martensite. In the martensite, on the contrary, the plastic deformation remains low but the carbon content decreases. This is caused by a stress-induced precipitation of carbides.

The non-destructive X-ray diffraction method is usually employed to evaluate stress states at the near surface of materials. In specific zones with high-stress gradients parallel to the surface, like welding joins, areas affected by lasers, or ball-bearing raceways, the classical measurement method is not particularly well suited, as the irradiation spot covers regions of varying stress according to its size. This leads to inaccurate stress evaluations. A new X-ray diffraction measurement and data treatment method is therefore proposed. It is based on longitudinal step-by-step scanning in a fixed direction of the surface. As the acquired data results from the convolution of local diffraction peaks with the incident-beam intensity, an accurate model of the true two-dimensional intensity distribution inside the spot has been developed. Firstly, the true shape and size of the irradiation area is defined. The distribution of the intensity received by the sample surface is then computed. The true local strains and stresses along the scanning direction are finally determined from the acquired peaks using an optimization through a least-squares fitting by a nonlinear function.

L’objectif majeur de cette etude est de simuler le comportement en fatigue thermique d’un rouleau de coulee continue. Cette modelisation a necessite la mise en place d’un banc de simulation experimentale reproduisant les conditions reelles de fonctionnement. Le cylindre teste a ete revetu d’un acier inoxydable martensitique de nuance proche du X12Cr13, depose par torche plasma sur un acier de nuance 25CrMo4. L’evolution thermique du cylindre a ete enregistree en fonction du temps par des thermocouples implantes a differentes profondeurs et egalement par un pyrometre infrarouge pour les mesures de surface. Le champ thermique est ensuite calcule numeriquement par la resolution d’un probleme inverse ou sont optimises les parametres des lois de la thermique (flux thermique et coefficients de convection) en minimisant l’ecart entre la base experimentale et les resultats du calcul par elements finis. Suite a cette phase d’optimisation, un calcul mecanique anisotherme de la structure par la methode des elements finis est effectue en utilisant le chargement thermique optimise et la loi de comportement elastoviscoplastique des deux materiaux dont les parametres ont ete prealablement determines dans la gamme des temperatures de fonctionnement de l’outillage. Cette simulation numerique constitue un outil de choix technologiques, quant au type de revetement a utiliser et a son epaisseur optimale. Elle nous permet egalement de tester l’outillage dans des conditions de mise en service severes, notamment lors d’un ralentissement ou d’un arret du rouleau.

In gear industry, cyclic contact leads to a damage of the superficial layers and generates residual stresses onto the work-hardened surface. The study of this stress state allows to characterize some wear mechanisms. However many measurements carried out by X-ray diffractometry reveal high lateral stress gradients in the wear track perpendicular direction which perturb the results obtained by this technique. It is therefore necessary to develop a new measurement and data treatment strategy to determine the local stress state at a given point of the material. The method proposed in our paper is based on a step-by-step strain scanning along a fixed direction of the surface. The step size is selected in connection with the amplitude of the lateral stress gradients. At each step, the lattice strain measurement integrates the whole elementary diffraction peaks of the points belonging to the irradiated area. The acquired data result therefore from the convolution of these local peaks with the intensity of the incident beam. An accurate modeling of the true 2D-intensity distribution inside the spot has been developed for that purpose which accounts for the actual measurement conditions: shape and size of the X-ray tube focus, diameter of the incident beam collimator, diffraction angle and (o, ψ) measurement direction. It first defines the true shape and size of the irradiation area. The distribution of the intensity received by the sample surface is then computed. The true local strains and stresses along the scanning direction are finally determined from the acquired peaks using an optimization through a least squares smoothing requiring a non linear function.

The life cycle of Dendrobaena veneta was studied to assess the potential of breeding this species for the fish-bait market. Development, growth and reproduction were investigated by rearing worms at 10°, 15°, 20° or 25°C on horse manure or on aerobic paper sludge for 6 months. At 10°C, the maturity was slow with a long period of development (104 d) and a low cocoon production. Productivity at 25°C was better than at 20°C or 15°C. The effect of temperature on cocoon production differed according to the source of food; on paper sludge, cocoons were produced at the same rate at 20 or 25°C while on horse manure cocoon production was better at 25°C than at 20°C. Whatever temperature, cocoon production was significantly greater on paper sludge than on horse manure. On paper sludge, maturation of juveniles was faster and adult worms larger. Adults started to produce cocoons at a younger age and more cocoons were produced worm −1 and d −1 . These results showed that the life cycle of D. veneta may be influenced by the type of food and that horse manure is not the best substrate for breeding this species.

Many treatment options for AMD, like wetlands and anoxic limestone drains, are limited by acidity, metal loadings, flow rate or areal requirements so as to be inapplicable at many sites. In-situ bacterial sulfate reduction is proposed as a solution for certain settings. Requirements for successful in-situ bacterial sulfate reduction include dissolved sulfate, an organic substrate, permanent anaerobic conditions, a mixed culture of bacteria, appropriate nutrients, and a sufficient AMD contact time. These requirements can be provided within mine spoil by injection of waste organic matter into an extensive zone of saturated spoil. Laboratory experiments on cheese whey, lactate, non-degraded sawdust, partially degraded sawdust, pulped newspaper and mushroom compost have all yielded sulfate reduction, increased alkalinity and iron sulfide precipitate in AMD with pH < 4.0. The addition of a small amount of dolomite to the organic matter creates alkaline microenvironments that facilitate the initiation of sulfate reduction. The rates of sulfate reduction using cellulose materials are slow but the rate for milk products is much more rapid. A field test utilizing partially degraded sawdust is underway. A total of 11.3 tons of sawdust mixed with 5% dolomite, 5% sewage sludge and a mixed bacterial culture was successfully injected into 4more » drill holes in mine spoil as 13% w/v suspension, The spoil had enough coarse porosity for injection into the saturated subsurface at about 300 L/min, Data on in-situ SO{sub 4} reduction rates and water quality are being collected in preparation for a full remediation program at the site, which has an extensive zone of saturated spoil 10-20 m thick.« less

Allozymes at a maximum of eight loci were used to analyse the spatial patterns of genetic variation in 1942 holm oak trees (Quercus ilex L.) from 57 provenances distributed in the six main disjunct areas of the species distribution area. Polymorphism and genetic diversity were high except in the six marginal populations growing in various locations under unfavourable climatic conditions. Ten per cent of the total genetic diversity (Ht = 0.262) was accounted for by among-population variation. In this long-lived species, the effect of geographical discontinuities on gene flow restriction was shown by the occurrence of: (i) numerous rare alleles limited to a single disjunct region; and (ii) allele frequency variation among the disjunct regions for four alleles. This result was obtained by comparing spatial autocorrelograms from the 57 populations of the entire distribution area and from the 31 populations of the Mediterranean continental region which constitutes the largest continuous area in that distribution. Life history traits (e.g. long life span and high outcrossing rate) and past changes in climate and geographical continuity are assumed to be the main factors responsible for the present genetic variation patterns observed in the species.

A method for the extraction of ctDNA from isolated chloroplast was developed. This method is simple and adapted particularly to broad-leaved trees, including sclerophyllous species with high phenolic and polysaccharide contents. This method includes two major steps: first, chloroplasts are isolated in non-aqueous solutions to avoid oxidation and phenolic problems; second, ctDNA is extracted from the chloroplasts using aqueous solutions and specific methods to provide highly purified ctDNA.

Reclamation efforts on Abandoned Mine Lands, by the Pennsylvania Department of Environmental Resources (PA DER) and by mining companies, have resulted in vast improvements in the conditions of these sites. However, little work has been done to evaluate and document the success of individual reclamation techniques and to adopt techniques that have the highest success at reducing erosion and improving water quality. Working with the Bureau of Abandoned Mine Reclamation, PA DER, The Pennsylvania State University developed an evaluation system called the Reclamation Success Evaluation System or RSES. This system evaluates the success of individual reclamation efforts by looking at three main criteria: (1) Surface Water Quality, (2) Extent of Erosion, and (3) Success of the Vegetative Cover. In order to test the field implementation of the RSES, and to aid in the development of the evaluation system, it was used to evaluate reclamation efforts in a drainage basin in central PA. This site, the Montgome...

For its outstanding piezoelectric coefficients, thin-film sol-gel Pb(Zr0.52,Ti0.48)O3 (PZT) has been widely studied over the past few decades. In particular, the impact of Zr/Ti ratio control on e31,eff coefficient has been investigated at low fields. Yet, when it comes to actuation, PZT films are used with electric fields higher than the coercive field. In this paper, the influence of Zr/Ti gradient reduction on e31,eff coefficient is investigated in actuating conditions, ie under high fields.

This paper reports on the optimization of electrodes design for sol-gel Pb(Zr0.52, Ti0.48)O3 (PZT) thin-film actuatedmembranes. PZT can be used in many actuator applications such as micro mirror, RF MEMS, inkjet or loudspeaker due to its strong piezoelectric properties. We aim to design membrane-based actuators with the optimum electrode dimensions allowing the largest membrane displacement under a given actuation voltage. We present in this paper measurement results, in good agreement with the finite element modeling, proving that an actuator area between 50 and 60% of the membrane area exhibits the highest deflection. © 2012 Published by Elsevier Ltd.

Our study examines how individuals decide which scientific claims and experts to believe when faced with competing claims regarding a policy issue. Using an experiment in a public opinion survey, we test the source content and credibility hypotheses to assess how much confidence people have in reports about scientific studies of the safety of offshore oil drilling along the California coast. The results show that message content has a substantial impact. People tend to accept reports of scientific studies that support their values and prior beliefs, but not studies that contradict them. Previous studies have shown that core values influence message acceptance. We find that core values and prior beliefs have independent effects on message acceptance. We also find that the sources of the claims make little difference. Finally, the public leans toward believing reports that oil drilling is riskier than previously believed.

Ce travail a porte sur un revetement base cobalt, depose par torche plasma et destine a augmenter la duree de vie de cylindres de laminoir soumis a des degradations dues a la fatigue thermique. La microstructure du depot a ete etudiee a l'aide de methodes classiques d'investigation : microscopie optique et electronique, diffractometrie X, avant et apres sollicitation en fatigue thermique. Le mode de deformation du revetement en fatigue thermique a pu etre identifie : la transformation martensitique. Par ailleurs, un autre type d'analyse, la diffraction neutronique, a permis de mettre en evidence que le revetement presentait une importante texture cristallographique ; il apparait donc que ce parametre est a prendre en compte dans ce type d'etude, car il est de nature a influer sur la tenue et le comportement mecanique d'un tel revetement subissant des sollicitations purement thermiques, mais aussi mecaniques.

The use of a laser beam for surface alloying with carbide powder injection gives thick coatings (750–800 μm) without defects such as porosity and cracks. A precise correlation between the treatment parameters and the phenomena induced during the laser-material interaction is established. Optimum treatment conditions are found and applied to laser alloying of 4140 and high speed M2 tool steels with tungsten carbide injection. The laser surface treated zones, for both steels, are strongly alloyed and present a very fine microstructure with various morphologies and very high average values of the microhardness (900 HV 50 gf and 1200 HV 50 gf) compared with those of the substrates (300 HV 50 gf and 250 HV 50 gf respectively). Friction and wear tests (using a plane-ring experimental device), revealed that the laser surface coatings on both steels present wear resistances considerably higher than that of a conventional plasma-sprayed coating.

There are a large number of variables that must be taken into account for the development of a dragline mine plan. This is especially true for mining in mountainous terrain, where the geology and topography may be complex. As a result, the manual mine planning process can be very tedious and time consuming An interactive computer package was developed in order to aid the engineer with dragline mine planning on a PC based system. This package employs recent advances in 3D computer graphics and 3D geologic modelling to help with the visualization of the mine plan and to speed up the planning process One of the main difficulty with the development of mine planning software for microcomputers is due to the limited amount of available RAM (Random Access Memory). This, in turn, affects the speed of information retrieval from the database and the speed of data processing. A compact geologic and mine model and an efficient database were developed to overcome these limitations. These components where then...

• Background and Aims In the last decades, the geographical location of the centre of origin of Quercus suber (cork oak), a strictly western Mediterranean oak species, has been the subject of controversy. • Methods RFLP variation over the whole chloroplast DNA molecule and PCR–RFLPs over seven specific cpDNA fragments were analysed phylogeographically to reconstruct the evolutionary history of cork oak. • Key Results Nine chlorotypes of the ‘suber’ cpDNA lineage were identified throughout the species range. Using closely related Mediterranean oak species as outgroup, the chlorotypes showed a clear phylogeographical pattern of three groups corresponding to potential glacial refuges in Italy, North Africa and Iberia. The most ancestral and recent groups were observed in populations located in the eastern and western parts of the species range, respectively. Several unrelated chlorotypes of the ‘ilex’ cpDNA lineage were also identified in specific western areas. • Conclusions The results support a Middle-Eastern or a central Mediterranean origin for cork oak with subsequent westward colonization during the Tertiary Period, and suggest that the ‘ilex’ chlorotype variation does not reflect entirely cytoplasmic introgression by Q. ilex but originated partly in Q. suber.

Butyltins (BTs) were determined in sediment, zooplankton, benthic fish and invertebrates in the St. Lawrence Estuary and its mixing zone with the Gulf of St. Lawrence (Canada) in an attempt to assess sources and fate of these compounds in a large ecosystem before the enforcement of the world-wide ban of TBT-based antifouling paints. All BTs (MBT, DBT and TBT) were found along the studied area (450 km) where the traffic of large vessels occurs around the year. Concentrations of total butyltins (BTs) in surface sediment were below 6 ng Sn g −1 d.w. Total BTs concentrations found in zooplankton samples at the mouth of the Saguenay Fjord were the highest (793 ng Sn g −1 d.w.), indicating the influence of the Fjord on the St. Lawrence contamination. Although a relatively low contamination level was measured in sediment, total BTs concentrations ranged from 9 to 489 ng Sn g −1 d.w. for benthic organisms. Biota-sediment accumulation factors (BSAFs), calculated on the basis of the organic carbon content in the sediment (concentrations normalized to 1% Corg), ranged from 0.9 to 98.3, and are an indicator of an important source of BTs from the Saguenay Fjord particulate matter. This may be explained by the fact that when TBT is released in a large and deep well stratified coastal environment, it could bind to the suspended particulate matter and then be taken in charge by water column organisms and may be mostly metabolised before it reaches bottom sediment. Sediment is not considered as the main contributor to the contamination of fish and invertebrates. It is expected that any reduction of direct inputs of TBT from ship hulls in a near future should result in a rapid reduction of butyltins in the St. Lawrence ecosystem.