Trente ans et mille personnes diplômées en 2007 : l’enseignement de la common law en français à l’Université d’Ottawa

À l’approche du 30e anniversaire du programme de common law en français, quatre chercheuses et chercheurs ont entrepris de dresser le bilan des investissements sur le plan des études de common law en fran­çais et du rayonnement subséquent des juristes ainsi formés sur la scène canadienne. L’objet était de mesurer les effets que ces juristes ont eus sur la profession juridique, dans les communautés de langue offi­cielle en situation minoritaire et, plus généralement, sur l’accès à la justice en français. Ce texte présente les résultats de cette recherche en insistant sur le profil des personnes diplômées, sur leur contribution à l’essor des services juridiques en français, enfin sur le rôle du gouverne­ment et du programme dans la vitalité des communautés de langues officielles. Malgré les obstacles qui persistent, les personnes diplômées de ce programme jouent indéniablement un grand rôle auprès des franco­phones qui cherchent à se prévaloir de leurs droits à des services juridiques dans leur langue.With the advent of the French Common Law Program’s 30th anniversary, four researchers undertook an appraisal study of the investments with regards to common law training in French, and the subsequent influence of these graduates nationally. The objective was to evaluate the impact of the Program’s graduates on the legal profession, on official language minority communities and overall, on access to justice in French. This article presents the results of this study with an emphasis on the profile of graduates, their contribution to the expansion of legal services in French, and the government and Program’s role in the vitality of official language communities. Despite enduring obstacles, French Program graduates do undeniably assist Francophones at great length in availing themselves of their right to legal services in their own language

Resistance to quambalaria shoot blight and myrtle rust in Corymbia calophylla seedlings

Abstract Corymbia calophylla (marri), an endemic keystone tree species in southwest Western Australia, is increasingly impacted by the introduced basidiomycete smut Quambalaria pitereka. The basidiomycete rust Austropuccinia psidii (myrtle rust), an invasive pathogen recently introduced to Eastern Australia, is expected to spread to the southwest of Western Australia eventually. Austropuccinia psidii has similar epidemiology to Q. pitereka, and there is concern that C. calophylla may be susceptible. Preliminary pathogenicity tests showed significant differences in aggressiveness between twelve Q. pitereka isolates, and there was evidence of interactions between isolates and C. calophylla provenances. Seedlings from 59 open-pollinated families from 11 provenances covering the natural range of marri were screened for resistance to Q. pitereka and A. psidii under controlled glasshouse conditions. Resistance of seedlings within provenances to Q. pitereka and A. psidii differed significantly. There was no significant correlation between resistance to Q. pitereka and resistance to A. psidii. Seedlings of provenances from wetter regions were more resistant to both pathogens, but the correlation coefficients were insignificant. Seedlings of four families in three provenances (Serpentine, Chidlow, and Kingston) showed 100% resistance to Q. pitereka. Narrow-sense heritability estimates were 0.07 for quambalaria shoot blight resistance and 0.34 for myrtle rust resistance. The results indicate the potential to use selected families/individuals resistant to Q. pitereka and A. psidii for tree improvement programs and adaptive management strategies

Towards a best practice methodology for the detection of Phytophthora species in soils

The genus Phytophthora contains species that are major pathogens worldwide, affecting a multitude of plant species across agriculture, horticulture, forestry, and natural ecosystems. Here, we concentrate on those species that are dispersed through soil and water, attacking the roots of the plants, causing them to rot and die. The intention of this study was to compare the soil baiting protocol developed by the Centre for Phytophthora Science and Management (CPSM) with two other baiting methods used in Australia. The aim was to demonstrate the effectiveness of each protocol for soil baiting Phytophthora species in different substrates. Three experiments were conducted: the first to test the sensitivity of each method to detect Phytophthora cinnamomi, the second to test the effect of substrate type (sand or loam), and the third to test the detection of species (P. cinnamomi, P. multivora, or P. pseudocryptogea). The specificity of different plant species baits was compared within and between the methods. Substrate type influenced isolation in all methods; however, the CPSM method was superior regardless of substrate, albeit slower than one of the other methods for one substrate. Comparing bait species between the three methods, Quercus ilex was the most attractive bait for P. cinnamomi, particularly in the CPSM method. The choice of protocol affected the isolation associated with each bait type. Overall, the multiple bait system used by CPSM was shown to provide the most sensitive and reliable detection of Phytophthora species from soil samples.info:eu-repo/semantics/publishedVersio

Anthropogenic disturbance impacts mycorrhizal communities and abiotic soil properties : implications for an endemic forest disease

In forest ecosystems, habitat fragmentation negatively impacts stand structure and biodiversity; the resulting fragmented patches of forest have distinct, disturbed edge habitats that experience different environmental conditions than the interiors of the fragments. In southwest Western Australia, there is a large-scale decline of the keystone tree species Corymbia calophylla following fragmentation and land use change. These changes have altered stand structure and increased their susceptibility to an endemic fungal pathogen, Quambalaria coyrecup, which causes chronic canker disease especially along disturbed forest habitats. However, the impacts of fragmentation on belowground processes in this system are not well-understood.We examined the effects of fragmentation on abiotic soil properties and ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungal communities, and whether these belowground changes were drivers of disease incidence. We collected soil from 17 sites across the distribution range of C. calophylla. Soils were collected across a gradient from disturbed, diseased areas to undisturbed, disease-free areas.We analysed soil nutrients and grew C. calophylla plants as a bioassay host. Plants were harvested and roots collected after 6 months of growth. DNA was extracted fromthe roots, amplified using fungal specific primers and sequenced using Illumina MiSeq. Concentrations of key soil nutrients such as nitrogen, phosphorus and potassium were much higher along the disturbed, diseased edges in comparison to undisturbed areas. Disturbance altered the community composition of ECM and AM fungi; however, only ECM fungal communities had lower rarefied richness and diversity along the disturbed, diseased areas compared to undisturbed areas. Accounting for effects of disturbance, ECM fungal diversity and leaf litter depth were highly correlated with increased disease incidence in C. calophylla. In the face of global change, increased virulence of an endemic pathogen has emerged in this Mediterranean-type forest.The Holsworth Wildlife Research Endowment, the Australasian Mycological Society and the Australian Research Council Linkage LP120200581.https://www.frontiersin.org/journals/forests-and-global-change#am2022BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Anthropogenic disturbance impacts stand structure and susceptibility of an iconic tree species to an endemic canker pathogen

Forest ecosystems characterised by higher tree species diversity have been linked to a reduced susceptibility to pathogens. Conversely, endemic pathogens contribute to forest ecosystem dynamics and process. In the face of global change, however, negative impacts arising from more frequent and severe forest disturbances are increasingly observed. An increase in the susceptibility of Corymbia calophylla, a keystone tree species of southwest Western Australia, to cankers caused by the endemic fungus Quambalaria coyrecup, has emerged in recent decades. Landscape scale assessment of disease incidence has implicated the predisposing role of anthropogenic disturbance, indicating a need for this to be examined at a finer resolution. We assessed the effects of anthropogenic disturbance on the incidence of canker disease caused by Q. coyrecup across a disturbance gradient at 17 forest sites. In addition, we determined the impact of disturbance on tree community composition and stand level structural traits including stem density and stand basal area, and investigated the role of these factors as drivers of canker presence. Canker incidence and associated mortality of C. calophylla increased with anthropogenic disturbance. Disturbed edges showed significantly different overstorey composition from the forest transects. Total stem density increased with increasing disturbance, and disturbed edges contained greater numbers of C. calophylla stems compared to forest transects. There was a much increased basal area of C. calophylla on disturbed edges. Regardless of transect position, an increased incidence of canker resulted on sites with increased C. calophylla basal area. Lastly, increased tree species diversity (as measured by species richness) was associated with decreased canker incidence. We demonstrate that anthropogenic disturbance has altered stand structure and led to an increased susceptibility of C. calophylla to Q. coyrecup, resulting in high disease incidence and mortality of trees on disturbed road edges. Our results highlight the complexity of addressing tree health issues in the presence of multiple global change factors.The Australian Research Council (Linkage Project 120200581) and conducted within the Western Australian State Centre of Excellence for Climate Change Woodland and Forest Health, which is a partnership between private industry, community groups, universities and the Government of Western Australia.http://www.elsevier.com/locate/foreco2019-10-01hj2018Forestry and Agricultural Biotechnology Institute (FABI)Microbiology and Plant Patholog

Pairing symmetry and long range pair potential in a weak coupling theory of superconductivity

We study the superconducting phase with two component order parameter scenario, such as, $d_{x^2-y^2} + e^{i\theta}s_{\alpha}$, where $\alpha = xy, x^2+y^2$. We show, that in absence of orthorhombocity, the usual $d_{x^2-y^2}$ does not mix with usual $s_{x^2+y^2}$ symmetry gap in an anisotropic band structure. But the $s_{xy}$ symmetry does mix with the usual d-wave for $\theta =0$. The d-wave symmetry with higher harmonics present in it also mixes with higher order extended $s$ wave symmetry. The required pair potential to obtain higher anisotropic $d_{x^2-y^2}$ and extended s-wave symmetries, is derived by considering longer ranged two-body attractive potential in the spirit of tight binding lattice. We demonstrate that the dominant pairing symmetry changes drastically from $d$ to $s$ like as the attractive pair potential is obtained from longer ranged interaction. More specifically, a typical length scale of interaction $\xi$, which could be even/odd multiples of lattice spacing leads to predominant $s/d$ wave symmetry. The role of long range interaction on pairing symmetry has further been emphasized by studying the typical interplay in the temperature dependencies of these higher order $d$ and $s$ wave pairing symmetries.Comment: Revtex 8 pages, 7 figures embeded in the text, To appear in PR

The Isotope Effect in d-Wave Superconductors

Based on recently proposed anti-ferromagnetic spin fluctuation exchange models for $d_{x^2-y^2}$-superconductors, we show that coupling to harmonic phonons {\it{cannot}} account for the observed isotope effect in the cuprate high-$T_c$ materials, whereas coupling to strongly anharmonic multiple-well lattice tunneling modes {\it{can}}. Our results thus point towards a strongly enhanced {\it{effective}} electron-phonon coupling and a possible break-down of Migdal-Eliashberg theory in the cuprates.Comment: 12 pages + 2 figures, Postscript files, all uuencoded Phys. Rev. Lett. (1995, to be published

Quambalaria shoot blight resistance in marri (Corymbia calophylla) : genetic parameters and correlations between growth rate and blight resistance

Quambalaria shoot blight (QSB) has emerged recently as a severe disease of Corymbia calophylla (marri). In this study, QSB damage and growth were assessed in Corymbia calophylla trees at 4 and 6 years of age in two common gardens consisting of 165 and 170 open-pollinated families representing 18 provenances across the species’ natural distribution. There were significant differences between provenances for all traits. The narrow-sense heritability for growth traits and QSB damage at both sites were low to moderate. The genetic correlation between QSB damage and growth traits was negative; fast-growing families were less damaged by QSB disease. Age-age genetic correlations for individual traits at four and six years were very strong, and the type-B (site–site) correlations were strongly positive for all traits. Provenances from cooler wetter regions showed higher resistance to QSB. The QSB incidence at 6 years was significantly correlated with environmental factors of the provenance’s origin. The QSB incidence at years four and six was not correlated with the QSB expression in 3-month-old seedlings. Based on these results, selection for resistance could be undertaken using 4-year-old trees. There is potential for a resistance breeding program to develop populations of marri genetically diverse and resistant to QSB.Open Access funding by CAUL and its Member Institutions. PhD scholarship between the Vietnamese Government and Murdoch University as well as the Australian Research Council Linkage Program.https://link.springer.com/journal/11295am2023Forestry and Agricultural Biotechnology Institute (FABI)BiochemistryGeneticsMicrobiology and Plant Patholog