1,966 research outputs found
World country and industry relationships in equity returns,
No full textForthcoming in Edwin Elton and Martin Gruber, eds., International capital markets.Bibliography: l. [26]by Donald R. Lessard
Probing the relationship between electromagnetic ion cyclotron waves and plasmaspheric plumes near geosynchronous orbit
No full textPlasmaspheric plumes created during disturbed geomagnetic conditions have been suggested as a major cause of increased occurrences of electromagnetic ion cyclotron (EMIC) waves at these times. We have catalogued occurrences of strong Pc1 EMIC waves from 1996 through 2003 at three automated geophysical observatories operated by the British Antarctic Survey at auroral zone latitudes in Antarctica (L = 6.28, 7.68, and 8.07) and have compared them to the occurrence of plasmaspheric plumes in space, using simultaneous data from the Magnetospheric Plasma Analyzer on the Los Alamos National Laboratory 1990-095 spacecraft, in geosynchronous orbit at the same magnetic longitude. A superposed epoch analysis of these data was conducted for several categories of disturbed geomagnetic conditions, including magnetic storms, high-speed streams, and storm sudden commencements. We found only a weak correspondence between the occurrence of strong Pc1 waves observed on the ground and either plasmaspheric plumes or intervals of extended plasmasphere at geosynchronous orbit before, during, or after the onset of any of these categories. Strong Pc1 activity peaked near or slightly after local noon during all storm phases, consistent with equatorial observations by the Active Magnetospheric Particle Tracer Explorers/Charge Composition Explorer satellite at these L shells. The highest Pc1 occurrence probability was at or 1-2 days before storm onset and during the late recovery phase. Occurrence was lowest during the early recovery phase, consistent with the decrease in solar wind pressure often seen at this time. The peak at onset is consistent with earlier observations of waves in the outer magnetosphere stimulated by sudden impulses and magnetospheric compressions
Hydrolyse basique des carboxamides secondaires N-méthylés fonctionnalisés en présence d'hypochlorite de sodium
No full textRoland Côté et Jean Lessard ont établi que les carboxamides secondaires N-méthylés s'hydrolysent bien en acides correspondants en présence d'hypochlorite de sodium alcalin. Dans le travail qui est présenté ici, nous nous sommes essentiellement attachés à étudier l'action de l'hypochlorite de sodium alcalin sur les carboxamides secondaires N-méthylés fonctionnalisés, afin de mieux saisir la portée de cette méthode d'hydrolyse en synthèse, sa sélectivité et l'utilisation du groupe amide secondaire comme groupe protecteur. Dans ce but, nous avons synthétisé un certain nombre de carboxamides secondaires N-méthylés fonctionnalisés, aliphatiques et aromatiques, contenant en plus du groupe amide secondaire un autre groupement fonctionnel: alcool, cétone, éther, ester, double liaison Ces substrats furent ensuite soumis à l'action de l'hypochlorite de sodium additionné d'hydroxyde de sodium, à la température de la pièce, en absence de lumière, sous une agitation vigoureuse
Lessard Claude & Meirieu Philippe (dir.). L’obligation de résultats en éducation. Évolutions, perspectives et enjeux internationaux
No full textLe livre coordonné par Claude Lessard et Philippe Meirieu est une réédition d’une publication, suite à un colloque organisé en automne 2000 à Montréal, dans le cadre des entretiens Jacques Cartier. Il n’a rien perdu de son intérêt et de son actualité. Car, comme écrit Claude Lessard, en introduction à l’ouvrage, l’« obligation de résultats », ou la « redevabilité » ou encore la « reddition des comptes », est bien un mode de régulation de l’éducation à l’échelle internationale. Il correspond à..
Microchrysa wrightae Lessard & Woodley 2020, sp. nov.
No full text<i>Microchrysa wrightae</i> Lessard & Woodley, sp. nov. <p>http://zoobank.org/NomenclaturalActs/ C3A3DED4-14DB-4E3E-8920-4866B5B1939C</p> <p>Figs 5, 6</p> <p> <b>Holotype</b> ♂, “Ingham, Qld. / Light Trap / 15 Mar. 1961 / K.I. Harley ”; “ HOLOTYPE ♂ / <i>Microchrysa wrightae /</i> Lessard & Woodley, 2020 ” ANIC 29-037422. The specimen is in excellent condition. <b>Paratypes</b> 13♀♀ [ANIC 29- 037423, 29-059047 to 29-059057, 29-059077], same data as holotype: “ PARATYPE ♀ / <i>Microchrysa wrightae /</i> Lessard & Woodley, 2020 ”; ANIC 29-059047, 29-059048 and 29-059052 collected 21 Mar.; ANIC 29-059049 and 29-059057 collected by R. Straatman on 20 and 27 Apr., respectively. 16♂♂ [ANIC 29-059032 to 29-059046, 29-037462], same data as holotype: “ PARATYPE ♂ / <i>Microchrysa wrightae</i> / Lessard & Woodley, 2020 ”; ANIC 29-059039 collected 5–12 Feb. 1963; ANIC 29-059040 and 29-059042 collected 21 Mar.; ANIC 29-059046 collected 27 Apr. by R. Straatman.</p> <p> <b>Other material examined:</b> Qld: 1♂ [ANIC 29-059058], 1♀ [ANIC 29-059059], 17.17S 145.34E, Curtain Fig, Feb 1988, D. C. F. Rentz; 1♂ [ANIC 29-059060], 2♀♀ [ANIC 29-059061, 29-059062], Mt. Bartle Frere (East Base), 80 ft, 25 Apr. 1955, Norris & Common; 1♂ [AMS K.453229], Whitfield Range, near Cairns, 3 April 1975, M. S. Moulds; 3♂♂ [ANIC 29- 059065, 29-059066, 29-059068], Ayr, 12-10-1950, E. F. Riek; 1♂ [ANIC 29-059067], same data as previous, 11-10-1950; 1♀ [ANIC 29-059070], same data as previous, 4-9-1950; 1♀ [ANIC 29-059072], same data as previous, 12-10-1950; 2♀♀ [ANIC 29-059069, 29-059071], Ayr, 30.ix.1960, R. Hughes; 3♂♂ [AMS K.453218–K.453220], 2♀♀ [AMS K.453216, K.453217], 15.50S 145.20E, 3 km N of Bloomfield, 21 Sep 1992, at light, P. Zborowski & L Miller; 1♂ [ANIC 29-059073], 3 mls W of Mossman, 13 Mar 1964, I. F. B. Common & M. S. Upton; 1♀ [AMS K.453224], Windsor Tableland, NW of Mossman, 810 m, 16°12'51"S 145°0.4'09"E, 4 Jan 1994, site 1, G. & A. Daniels, R. Eastwood mv lamp; D. H. Colless, at light: 1♀ [ANIC 29-059063], 15.04S 145.145.07E, Mt Webb Nat Pk, 29 Apr 1981; 1♀ [ANIC 29-059064], 15.03S 145.09E, 3 km NE of Mt Webb, 1 May 1981; 1♂ [ANIC 29-059074], 12 km SE of Daintree, 22 Nov 1981; 2♂♂ [ANIC 29-059075, 29-059076], 17.20S 145.31E, Wongabel State Forest, nrAtherton, 18 Nov. 1981; 2♂♂ [ANIC 29-059078, 29-059079], 15.50S 145.20E, Gap Ck, 5 km ESE Mt Finnigan, 14 May 1981; 1♂ [ANIC 29-059080], 15.29S 145.16E, Mt Cook Nat Park, 10 May 1981; 1♂ [ANIC 29-059082], 16.30S 145.00E, McLeod R., 14 km W by N of Mt. Carbine, 23 Nov 1981; 1♀ [ANIC 29-059081], 15.49S 145.14E, Little Forks Annan River, 18 Oct 1980, D. H. Colless, Malaise trap.</p> <p> <b>Diagnosis</b>. A small (length 5.0– 5.5 mm) species, with metallic golden or purplish green thorax, pale yellow legs with a dark brown marking on the apical half of the hind tibiae, and antennae and palpi yellow in males, darker brown in females. This species can be distinguished from <i>M. flaviventris</i> by the abdomen without green colouration in males (tergite 5 with green colouration in <i>M. flaviventris</i>), and both sexes with anterior portion of discal cell between <i>r-m</i> and <i> M 1</i> well developed and distinctly visible (faint in <i>M. flaviventris</i>; Woodley 2009), and hind femora entirely yellow (marked with dark brown apically in <i>M. flaviventris</i>), and the male terminalia with the posterior margin of the synsternite with a bilobed process with the lobes narrowly separated (deeply emarginate in <i>M. flaviventris</i>; Nagatomi 1975: fig. 4B).</p> <p> <b>Description</b>. <i>Male.</i> Length 5.0– 5.5 mm. <b>Head</b>. Eyes holoptic, contiguous about one-third the length of frons from vertex, with distinct demarcation of change in size of ommatidia just above antennae. Upper frons blackish, bare, lower frons diverging ventrally at margins, with a distinct linear impression, cuticular surface subshining, upper half pale brown, lower half black, hair-like setae relatively short, dense, golden; ocellar tubercle relatively bulging at each ocellus, ocelli almost in the shape of an equilateral triangle, slightly elongated anteriorly, black with reflections of green, hair-like setae relatively short, yellowish. Occiput not visible in lateral view, occipital plate relatively bare, with short, yellowish hair-like setae limited to lateral margins. Face wide, narrowly visible in profile, shining metallic green and gold, hair-like setae relatively short, dense, golden yellow. Antennae relatively s, scape+pedicel+flagellum about equal to length of head, scape about equal to length of pedicel, pedicel slightly expanded and curved gently apically on inner surface, both segments pale yellow, flagellum basal complex yellow, with small, irregular, circular presumably sensory pits, apical margin with short, golden hair-like setae, apical flagellomere yellowish brown, about 1.7 times as long as scape+pedicel. Palpi very short, yellow, with short, yellowish hair-like setae. Proboscis yellowish, with short, yellowish hair-like setae.</p> <p> <b>Thorax</b>. Scutum shining metallic golden green, occasionally with purplish reflections, with relatively short, dense, appressed, golden hair-like setae; scutellum slightly raised relative to scutum, same colour as scutum, with relatively short, dense, golden hair-like setae; mediotergite same colour as scutum, with a few moderately long, golden hair-like setae; pleura brownish with reflections of green to gold, with a prominent, narrow, whitish horizontal strip encompassing postpronotal lobe and upper margin of anepisternum, hair-like setae pale yellow to whitish. Legs with pale yellow coxae, femora, tibiae and tarsi, brown on apical half of hind tibiae, hair-like setae pale yellowish on all segments. Wings hyaline; cell <i> r 1</i> stained entirely pale yellow; <i> R 2+3</i> arising distal to <i>r-m,</i> exceeding length of discal cell; discal cell small, slightly elongate, about 1.3 times as long as wide; all medial veins terminating before reaching margin, <i> M 1</i> and <i> M 3</i> the weakest, both occasionally reduced to appendices or appearing as absent, <i> M 4</i> issued separately from discal cell by <i> dM 3+4</i> ; <i>CuA</i> relatively straight, curving at extreme end toward margin, petiole vein <i>CuA+CuP</i> short; alula large, slightly expanded and relatively pointed apically, surface without microtrichia; post-tegula yellowish, with yellowish hair-like setae; lower calypter with small straplike lobe present, hair-like setae dense, relatively long, pale golden yellow.</p> <p> <b>Abdomen</b>. Ovoid, about 1.2–1.4 times as long as wide, tergites 3–5 relatively quadrate, widest at tergite 5, cuticular surface pale yellow, contrasting with golden green thorax, hair-like setae short, dense, appressed, brown, becoming more yellow and erect at lateral margins, most obvious on tergites 2, 3 and apical margins of tergite 6. Sternites pale yellow, hair-like setae short, dense, appressed and entirely golden yellow. Terminalia yellowish brown: gonostyli semitriangular, relatively acutely pointed posterolaterally, with a depressed groove at centre, hair-like setae relatively long, dense, brownish; gonocoxites nearly quadrate, evenly tapered anteriorly, posterior margin of genital capsule emarginate with a pair of rounded sublateral processes separated by a deep, quite narrow emargination, gonocoxal apodemes relatively short, not reaching anterior margin, anteriorly pointed; epandrium relatively short, anterior margins blunt, rounded laterally, proctiger wider than long, semi-triangular, cerci longer than wide, rounded at tip, exceeding length of proctiger, hair-like setae long, dense, brownish.</p> <p> <i>Female.</i> Length 5.0– 5.5 mm. Similar to males, but slightly more bluish purple in colouration on the thorax and the abdomen, abdomen is concolorous with the scutum. Eyes with ommatidia of uniform size, with extremely sparse, short, whitish hair-like setae. Frons wide (index 1.4–1.5), with a strong medial impression, margins converging ventrally, shining metallic purplish to aqua blue, with relatively sparse, short, dull yellowish white setae, lower frons with a pale yellowish brown horizontal band. Occiput well developed, shining metallic purplish to aqua blue, dorsal half visible in lateral view. Antennae darker yellowish brown. Palpi dark brown. Abdomen with tergites blackish with strong reflections of green to purplish blue, concolorous with thorax, lateral hair-like setae whitish; sternites dark brown to black, with subtle bluish reflections, hair-like setae whitish.</p> <p> <b>Distribution</b>. Northern Qld (Fig. 2).</p> <p> <b>Etymology</b>. This specific name is in honour of Susan Wright, Collection Manager of Entomology, QM, for assistance and access to the collection.</p> <p> <b>Remarks</b>. At least four undescribed species of <i>Microchrysa</i> are known in collections from: <i>(a)</i> Pine Creek and Curtain Fig, Qld [ANIC 29-059299 to 29-059301]; <i>(b)</i> Townsville to Brisbane, Qld [7♂♂ ANIC 29-059289, 29-059290, 29- 059291, 29-059292, 29-059293, 29-059295, 29-059298; 3♀♀ ANIC 29-059291, 29-059294, 29-059295; 1♀ AMS K.453226, 3♂♂ AMS K.453230–K.453232; 1♀ USNM; 2♂♂ QM] and Carnarvon Golf Club, NSW [9♀♀ AMS K.478683–K.478691]; <i>(c)</i> Davies Creek, Qld, [N.E. Woodley Collection donated to USNM]; and <i>(d)</i> Kutini-Payamu (Iron Range) National Park [AMS K.453227, K.453225]. Material is also known from Berry Springs, Larrakeyah, Casuarina Point, Black Point, and Rimbija Islands, NT, that superficially resemble <i>M. wrightae</i>.</p> <p> Although little is known regarding the biology of the Australian sargine fauna, this genus appears to be associated with vegetation, based on collection labels of specimens belonging to three undescribed species: two specimens from Brisbane (AMS K.453231, K.453232) were collected from leaves of <i>Physallis peruviana</i> (Solanaceae); a series of females from Carnarvon Golf Club, NSW (AMS K.478683–K.478691) were collected from a woodchip pile, and; a female from Snake Bay (presumably NT; ANIC 29-059096) and male from Melville Island (NT, ANIC 29-059101) were collected from the native shrub <i>Opilia amentacea</i> (Opiliaceae).</p>Published as part of <i>Lessard, Bryan D., Yeates, David K. & Woodley, Norman E., 2020, Review of Australian Sarginae Soldier Fly Genera (Diptera: Stratiomyidae), with First Records of Cephalochrysa, Formosargus and Microchrysa, pp. 23-43 in Records of the Australian Museum 72 (2)</i> on pages 30-33, DOI: 10.3853/j.2201-4349.72.2020.1683, <a href="http://zenodo.org/record/4654320">http://zenodo.org/record/4654320</a>
Des approches sociologiques de la formation des maîtres
No full textClaude Lessard describes four sociological approaches of teacher training. These approaches attribute more or less importance to training in the development of the professional identity of teachers.
- The symbolic-interactionist approach.
- The structural-fonctionalist approach.
- The marxist approach.
- The approach in terms of field.
The author invites us not to consider those four approaches as exclusive but rather to replace them on a continuum going from the actors and their links with the training system to the training system itself and its relations with the educational system and society.
If the sociology of teacher training wants to be something more than a plurality of perspectives, it has nowadays to search for its own coherence.Claude Lessard nous propose quatre approches sociologiques de la formation des maîtres, approches qui accordent plus ou moins d'importance à la formation dans la constitution de l'identité professionnelle des maîtres.
- L'approche symboliste-interactionniste.
- L 'approche structuro-fonctionnaliste.
- L'approche marxiste.
- L 'approche en terme de champ.
L 'auteur nous invite à ne pas considérer ces quatre approches comme exclusives mais à les replacer dans un continuum allant des acteurs et de leurs rapports au système de formation, à ce système de formation et à ses rapports avec le système éducatif et la société.
Si la sociologie de la formation des maîtres veut être autre chose qu'une pluralité de perspectives, elle doit aujourd'hui rechercher sa propre cohérence.Lessard Claude, Lahaye Louise, Tardif Maurice. Des approches sociologiques de la formation des maîtres. In: Recherche & Formation, N°4, 1988. Les professions de l'éducation : recherches et pratiques en formation. pp. 51-66
Metal toxicity assessment in soils using enzymatic activity: Can water be used as a surrogate buffer?
No full textEcotoxicological tests based on soil enzyme activity are widely used to assess the terrestrial ecotoxicology of metals in soils. However, several standard enzymatic methods use buffers that may alter the chemical pseudoequilibrium of soils and affect metal speciation, and, in turn, the metal effects on enzymes and enzyme kinetics. Researchers have suggested the use of H2O as a solvent rather than chemical buffers, but opponents are concerned about pH fluctuations during incubation and the resulting difficulty in comparing enzymatic studies. Enzyme assays were conducted on 10 pairs of Zn-contaminated soils to evaluate 1) the buffer effect on Zn lability 2) the pH fluctuation during enzymatic assays conducted in water and 3) the comparison of enzymatic results obtained using chemical buffers versus water. Four standard enzymatic methods covering the major biogeochemical cycles were targeted: arylsulfatase (acetate pH 5.8), urease (borate pH 10), acid phosphatase (modified universal buffer pH 6.5) and protease (THAM pH 8.1). Furthermore, deionized water was tested in parallel as a surrogate solvent for these four methods. With the exception of the acetate buffer, the tested solvents did not significantly change the labile Zn concentration in the soil samples. The pH slightly fluctuated by +0.57 pH unit, corresponding to the intrinsic variability of soils. Enzymatic methods using buffers showed similar results compared to those using water, except for urease. These observations suggest that enzymatic methods setting alkaline conditions should be used with caution and that H2O could be used as surrogate solvent in this context
Which genes are best indicators for lesion age determination on the pig carcass? A preliminary study.
No full textAssessing the age of lesions on the carcass may help determine the time of their infliction and identify the causes. This study aimed at identifying which genes are the best indicators of lesion age on the pig carcass. Five identical lesions were inflicted at the same time on the shoulders of 10 pigs (100± 20 kg) using a piglet’s lower jaw. Five biopsies on each pig were performed at 1, 4, 8, 24 and 48h after injury (1 biopsy per lesion). Intact skin was the control. Local anaesthetic and analgesics were used to reduce pain. To assess the effect of slaughter and carcass treatment on gene expression, 5 of the 10 pigs were slaughtered 24h after the infliction of two lesions in the hams. Biopsies were taken before and after slaughter (BS and AS, respectively), and after carcass singeing. The qPCR method was used to quantify the expression of 98 genes involved in wound healing, using the 2^(-CT) method. Since carcass handling induced a degradation of the RNA, only samples taken before carcass dehairing were used. Genes that were not differently expressed between BS and AS were first tested on 5 pigs in all lesion age categories. Fourteen selected genes were then tested on all pigs. Statistical analyses were performed using the PROCMIXED procedure of SAS. Eight genes (CCL2, COX2, IL2, IL6, IL8, MMP1, SERPINE1, TIMP1) presented different expression patterns by the age of the lesion (P<0.05). In particular, COX2 appears to be a useful indicator of lesions of 1h (1h=6.2 [3.2-12.1], 4h=1.4 [0.7-2.6], 8h=1.7 [0.9-3.4], 24h=1.6 [0.8-3.1], 48h=1.1 [0.6-2.2]; P<0.01), and MMP1 of 4-8h (1h=1.9 [0.7-5.5], 4h=35.6 [12.4-102.3],8h=19.2 [6.7-55.3], 24h=4.0 [1.4-11.4], 48h=1.3 [0.4-3.6]; P<0.001). Based on their different expression by age of lesion, the identified genes may be used in larger-scale studies to validate on-field methods for this assessment
La réduction électrochimique de N-haloamides dans l'acetonitrile
No full textLa réduction électrochimique des N-haloamides dans l'acétonitrile conduit au bris de la liaison azote-halogène et fait intervenir un transfert biélectronique. La réduction des N-haloamides primaires amène la formation de l'amide correspondant et de l'anion (base conjuguée) du N-haloamide selon un mécanisme d'échange de protons de type "père et fils". La réduction des N-haloamides secondaires génère l'anion d'amide qui peut être piégé par différents agents alkylants. Des essais de piégeage du radical amidyl intermédiaire qui résulterait de l'insertion d'un premier électron ont été négatifs, ce qui montre que l'introduction du deuxième électron est très rapide. Le comportement électrochimique des N-haloamides secondaires (coulométries variables et inférieures aux valeurs attendues, phénomènes de surface, etc.) présente un parallèle avec celui de différents halogénures organiques. Les N-fluorouréthanes sont beaucoup plus difficiles à réduire que les autres N-haloamides. Ils sont également très réactifs en milieu basique. Cette grande réactivité est mise en évidence par la formation du carbéthoxynitrène résultant de l'élimination a de l'ion fluorure à partir de l'anion (base conjuguée) du N-fluoro uréthane
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