Interfertility between Armillaria cepistipes and A. sinapina

Des études ont rapporté que des lignées européennes d'Armillaria cepistipes étaient interfertiles avec trois lignées américaines d'Armillaria désignées par les termes espèce biologique nord-américaine (NABS) V (A sinapina), NABS X et NABS XI. Une telle interfertilité entre les espèces soulève des doutes au sujet de l'utilisation de binômes latins distincts pour des espèces pouvant se reproduire. Cette interfertilité a été ré-examinée en mettant 24 isolats haploïdes d'A cepistipes européen en présence de 23 isolats 6'A. sinapina d'Amérique du Nord et d'Asie. Les appariements individuels ont été effectués de façon indépendante au moins une fois à l'Université Laval (Canada) et à NNRA Clermont-Ferrand (France). Des 420 appariements interspécifiques effectués à l'Université Laval, deux étaient positifs et sept étaient ambigus, pour un total de 2,1 % de tous les appariements. Des 506 appariements effectués à Clermont-Ferrand, 10 étaient positifs et 24 étaient ambigus pour un total de 6,7 % des appariements. Les différences dans les résultats de ces appariements peuvent être expliquées par les températures d'incubation, ainsi que par les différents types et concentrations d'extrait de malt utilisés dans chaque laboratoire. Les bas niveaux d'interfertilité trouvés entre A cepistipes et A. sinapina peuvent résulter de l'absence de barrières génétiques habituellement présentes entre des espèces sympatriques. Ce bas niveau d'interfertilité reflète des différences entre la morphologie, la répartition et les habitats des deux espèces d'Armillaria, et appuie la conservation de dénominations d'espèces distinctes.European strains of Armillaria cepistipes were reported to be interfertile with strains from three American Armillaria species known as North American Biological Species (NABS) V (A sinapina), NABS X and NABS XI. Such interfertility between species raises some doubts about using different Latin binomials for species capable of mating. This interfertility was reinvestigated by mating 24 haploid isolates of European A cepistipes with 23 isolates of A sinapinafrom North America and Asia. Individual pairings were independently performed at least once at Universite Laval, Canada and at INRA Clermont-Ferrand, France. From the 420 interspecific pairings performed at Laval, two were positive and seven were ambiguous for a total of 2.1% of all the pairings. From the 506 pairings made at Clermont-Ferrand, 10 were positive and 24 were ambiguous for a total of 6.7%. The differences in the pairing results may be explained by incubation temperatures, and the different types and concentrations of malt extract used at each laboratory. The low levels of interfertility found between A. cepistipes and A. sinapina may result from the absence of genetic barriers that are usually present between sympatric species. This low level of interfertility reflects differences in morphology, distribution, and habitat for these two species of Armillaria and this supports the retention of different species denominations

Validation of a blubber-based endocrine pregnancy test for humpback whales

Baleen whales have few identifiable external indicators of pregnancy state, making it challenging to study essential aspects of their biology and population dynamics. Pregnancy status in other marine mammals has been determined by measuring progesterone concentrations from a variety of sample matrices, but logistical constraints have limited such studies in free-swimming baleen whales. We use an extensive blubber sample archive and associated calving history data to retrospectively identify samples that correspond to pregnant females and develop a progesterone-based pregnancy test for humpback whales. The lowest pregnant blubber progesterone concentration was 54.97 ng g−1, and the mean for the known-pregnant group was 198.74 ± 180.65 ng g−1. Conversely, females known to be below the minimum age of sexual maturity (juvenile females) had an overall low mean progesterone concentration (0.59 ± 0.25 ng g−1), well below the known-pregnant range. Of the mature females that did not return with a calf (n = 11), three fell within the known-pregnant range (320.79 ± 209.34 ng g−1), while the levels for the remaining eight were two orders of magnitude below the lowest known-pregnant level (1.63 ± 1.15 ng g−1). The proportion of females that did not return with a calf but had values similar to known-pregnant females are consistent with rates of calf mortality, but other potential explanations were considered. Our findings support a validated blubber endocrine assignment of pregnancy corroborated with field life history information, a first for any baleen whale species. The progesterone values we measured were similar to those found in different pregnancy states of other cetaceans and support using blubber biopsy samples for assigning pregnancy in humpback whales. This method can be applied to existing archives or new samples to better study life history and population demography broadly across species and populations

A first record of Pestalotiopsis clavispora in Argan mass cutting propagation: Prevalence, prevention and consequences for plant production

A trial involving the mass propagation of Argania spinosa cuttings was established following two protocols: in mini-bouturathèques without mist and in a greenhouse under mist. Symptoms of petiole necrosis, foliar yellowing and abundant black acervuli were observed under both protocols. These symptoms were responsible for a 90% mortality rate in the mini-bouturathèques while under the mist treatment premature fatal necrosis of the apical buds resulted in 100% mortality. The disease’s causal agent, Pestalotiopsis clavispora, was identified on the basis of its morphological characteristics and by molecular analysis. Alternating weekly treatments of systemic and contact fungicides resulted in a 41% success rate in controlling this pathogen, described for the first time on argan cuttings.Deux approches différentes de bouturage de masse d’Argania spinosa ont été utilisées. La première consistait à enraciner les boutures dans des mini-bouturathèques sans brumisation, tandis que la deuxième consistait à utiliser une serre dotée d’un brumisateur. Des symptômes de nécrose des pétioles et de jaunissement des feuilles ainsi qu’une production abondante d’acervules noires ont été observés dans les deux protocoles. Dans les mini-bouturathèques, ces symptômes ont entraîné un taux de mortalité de 90 % des boutures, alors que sous brumisateur la nécrose précoce et fatale des bourgeons apicaux a engendré 100 % de mortalité. L’agent causal de la maladie, Pestalotiopsis clavispora, décrit pour la première fois sur les boutures d’arganier, a été identifié à partir de ses caractères morphologiques et par analyse moléculaire. Un traitement hebdomadaire à base de fongicide systémique et de fongicide de contact utilisés en alternance a permis de maîtriser cet agent pathogène avec un taux de réussite de 41 %

Examining the Skill Gap in Fashion Education

This research explores the importance of sewing skills within HE fashion education. Recent literature has identified significant discussion concerning a graduate skills gap at the onset of employment. Some industry specialists fear that educators are not doing enough to promote the technical side of fashion. As a consequence, there are concerns of a widening gap in the uptake of technical job roles within the fashion sector. This research investigates potential reasons why students might not make these career choices, focusing mainly on the teaching of construction skills through the development of a resource tool to enhance the curriculum to bridge this recognised gap. To contextualise the development of this project, literature has examined key areas of interest. These include studies relating to skill gaps, manufacture and production techniques as well as the relationship between technical skill and career interests. This research has applied a variety of methodologies, which have explored the skills required for fundamental sewing processes, the value of sewing from educational and industry perspectives and issues relating to the recognised skills gap and career choices. Methods have included object-based study, interviews with manufacturers and a focus group with second year BA (Hons) fashion design students undertaking pattern cutting and manufacture sessions. To evaluate the effectiveness of the resource tool of stitch and garment finishing techniques, questionnaires, observations and examinations were conducted with undergraduate students undertaking sewing sessions. This research has revealed that the resource tool was successful in engaging students with garment construction techniques, and that this was most beneficial when used in conjunction with other methods. During testing it was apparent that students preferred to work more creatively, using inventiveness over memory of previously taught sewing skills when producing samples. Interestingly, the research has also highlighted two distinctions; that further technical knowledge in sewing appears to, in some instances, have limited the creativity of students’ fashion design outcomes when advancing from a foundation to intermediate level of study. However, there is also evidence to suggest that further engagement with sewing had a positive influence on their understanding of garment construction informing feasible design. There appears to be minimal evidence that links strong sewing skill with the ambition to choose careers in the manufacturing sector. The conclusions from this research, including the testing results from the resource tool, support the development of a technical curriculum within the BA curriculum, and the development of a qualification level prior to BA

Invariant vector fields and the prolongation method for supersymmetric quantum systems

The kinematical and dynamical symmetries of equations describing the time evolution of quantum systems like the supersymmetric harmonic oscillator in one space dimension and the interaction of a non-relativistic spin one-half particle in a constant magnetic field are reviewed from the point of view of the vector field prolongation method. Generators of supersymmetries are then introduced so that we get Lie superalgebras of symmetries and supersymmetries. This approach does not require the introduction of Grassmann valued differential equations but a specific matrix realization and the concept of dynamical symmetry. The Jaynes-Cummings model and supersymmetric generalizations are then studied. We show how it is closely related to the preceding models. Lie algebras of symmetries and supersymmetries are also obtained.Comment: 37 pages, 7 table

Structural complexity inferred from anisotropic resistivity: Example from airborne EM and compilation of historical resistivity/induced polarization data from the gold-rich Canadian Malartic district, Québec, Canada

This paper is © 2019 Society of Exploration Geophysicists. The posting is available free of charge and its use is subject to the SEG terms and conditions: https://seg.org/Terms-of-UseStructurally complex zones within orogenic terranes typically correspond to areas where there is interference between multiple fold generations and are known to be favorable pathways for fluid flow because of their higher permeability. In the Canadian Malartic district, gold anomalies have been linked with zones of structural complexity that have been quantified by outcrop bedding orientation measurements and calculation of bedding variance maps. In this work, historical apparent resistivity and induced polarization data in the Canadian Malartic district were reprocessed and combined with new surveys to create a compilation of inverted chargeability and resistivity, which were then interpreted together with airborne electromagnetics and outcrop structural data. The results indicate chargeability anomalies, up to five times the background value, associated with the sulfide mineral content in monzodioritic dikes that are thickened in folds and hydrothermally altered. Although the airborne apparent half-space resistivity is mostly sensitive to conductive surficial cover, the inverted ground resistivity method is sensitive to deeper structure and likely represents bedrock signal at depths greater than 25 m. Inverted ground resistivity exhibits strong anisotropy in areas of subvertical bedding, where measured resistivities can vary by up to a factor of two, over the same location, depending on whether the survey lines are perpendicular or parallel to the strike of bedding. This result is observed at scales of 50 cm up to 100 m. Analysis of inverted ground resistivity together with bedding variance indicates a strong correlation between structurally complex zones with high bedding variance and a decrease in resistivity at depths greater than 25 m. This suggests that in places where the presence of disseminated gold cannot be directly detected, or where the outcrop exposure is limited due to overburden cover, geophysical data may still succeed in identifying structural complexity zones that could potentially host mineralization.Natural Sciences and Engineering Research Council of Canada and the Canada Mining Innovation Council (NSERC-CMIC Mineral Exploration Footprints Project Contribution 178

Loss of ATRX in Chondrocytes Has Minimal Effects on Skeletal Development

BACKGROUND:Mutations in the human ATRX gene cause developmental defects, including skeletal deformities and dwarfism. ATRX encodes a chromatin remodeling protein, however the role of ATRX in skeletal development is currently unknown. METHODOLOGY/PRINCIPAL FINDINGS:We induced Atrx deletion in mouse cartilage using the Cre-loxP system, with Cre expression driven by the collagen II (Col2a1) promoter. Growth rate, body size and weight, and long bone length did not differ in Atrx(Col2cre) mice compared to control littermates. Histological analyses of the growth plate did not reveal any differences between control and mutant mice. Expression patterns of Sox9, a transcription factor required for cartilage morphogenesis, and p57, a marker of cell cycle arrest and hypertrophic chondrocyte differentiation, was unaffected. However, loss of ATRX in cartilage led to a delay in the ossification of the hips in some mice. We also observed hindlimb polydactily in one out of 61 mutants. CONCLUSIONS/SIGNIFICANCE:These findings indicate that ATRX is not directly required for development or growth of cartilage in the mouse, suggesting that the short stature in ATR-X patients is caused by defects in cartilage-extrinsic mechanisms