Rôle des microorganismes sur la spéciation du Cu, Zn et Al dans la rhizosphère de sols forestiers

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Datos para la validación del cuestionario de Conductas Problemáticas del Asma de Creer et al.(1989) en una muestra española.

Se estudió la fiabilidad y validez del Cuestionario de Conductas Problemáticas del Asma con población asmática infanto-juvenil y el resultado obtenido es que sí que es un instrumento fiable y válido para detectar problemas conductuales asociados al asma en niños y jóvenes afectados de esta enfermedad.

Algunas consideraciones sobre el sencillo ejercicio propuesto por D. Gil et al. en un artículo reciente de esta revista.

Consideraciones que pueden resultar de utilidad sobre el 'sencillo ejercicio', tanto en el propio planteamiento, como en la resolución detallada. Se ha tratado de poner en evidencia lo rico y sencillo que resulta el análisis de este ejercicio, una vez familiarizados con el formalismo, en contraste con la complejidad, confusión y artificialidad, que siempre generan las simplificaciones apriorísticas; todo ello, mediante el estudio aparentemente simple de un movimiento; aspecto no trivial, el del estudio en movimiento, que está en el origen de la propia Física, desde los griegos. Para concluir, se expone la respuesta a estas consideraciones de J. Félix Fuertes, ya que el sencillo ejercicio no fue propuesto por los autores, sino que fue extraído de un texto de EGB.

Autoconcepto : evaluación y mejora en los alumnos de Ciclo Medio de EGB a través de un programa de intervención.

Siete hipótesis: el autoconcepto es un constructo multifacético de cuatro dimensiones no académicas y tres académicas. Existe un acuerdo estudiante-profesor en cuanto a la valoración del autoconcepto del alumno, aquellos alumnos que experimenten un programa para la mejora de su autoconcepto -académico o no académico- obtendrán una puntuación mayor, positiva y estadísticamente significativa, en relación con los alumnos de su misma clase que no hayan recibido tratamiento. Muestra general: 2069 alumnos y 65 profesores de tercero, cuarto y quinto de EGB. Muestra programa de intervención: 167 alumnos y 33 profesores de tercero, cuarto y quinto de EGB. Investigación de tipo cuasi-experimental sobre una muestra de alumnos, que busca clarificar: la estructura interna del autoconcepto, mediante análisis factorial aplicado a cuatro escalas de autoconcepto no académico, 3 escalas de autoconcepto académico y tres medidas totales y examinar su estructura externa, mediante matrices de correlación sobre 4 variables independientes. La variable dependiente es el autoconcepto y las independientes son: valoración inferida del profesor sobre el autoconcepto del alumno, logro y rendimiento académico, habilidad académica, edad y programa de intervención para la mejora del autoconcepto. Así se constata la validez del instrumento, los cambios en el autoconcepto, se realiza una evaluación continua de la intervención y se analizan los resultados. Adaptación del 'Self Description Questionnarire' -SDQ- publicado por Marsh, Parker y Smith -1983-. Valoración inferida del profesor sobre el autoconcepto del alumno -Marsh ET AL. -1983-. Test de lectura de Pérez González -1976-. Calificaciones académicas. Instrumentos utilizados por los profesores durante el programa de intervención para la mejora del autoconcepto. Programa informático SPSS. Análisis para la exploración de la estructura interna del autoconcepto: análisis factorial de primer orden y de orden superior. Análisis para la exploración de la estructura externa del autoconcepto: matrices multirasgo-multimétodos. Matrices de correlación 'R' de Pearson. Prueba 'T' de Wilcoxon.. El autoconcepto es multifacético. Sus dimensiones se organizan entre sí de manera jerárquica. Existe un acuerdo moderado entre diferentes facetas del autoconcepto de los alumnos y las valoraciones inferidas de sus profesores. Los indicadores académicos están significativamente correlacionados con dimensiones académicas del autoconcepto y no correlacionados con dimensiones no académicas. La intervención dirigida a los aspectos académicos del autoconcepto ha resultado significativa en todos los cursos. En relación con la intervención dirigida a los aspectos no académicos se han confirmado las hipótesis en cuarto de EGB, no así en tercero y en quinto de EGB. Fuerte apoyo para el modelo teórico de autoconcepto de Shavelson et al. -1976-. El SDQ representa un excelente instrumento para la medida del autoconcepto en alumnos de tercero, cuarto y quinto de EGB.

Reply to "Mega-highstand or megatsunami? Discussion of McMurtry et al. "Elevated marine deposits in Bermuda record a late Quaternary megatsunami": Sed. Geol. 200 (2007) 155-165" by Paul J. Hearty and Storrs L. Olson

Our recent paper [McMurtry, G.M., Tappin, D.R., Sedwick, P.N., Wilkinson, I., Fietzkc, J. and Sellwood, B., 2007a. Elevated marine deposits in Bermuda record a late Quaternary megatsunami. Sedimentary Geol. 200, 155-165.] critically re-examined elevated marine deposits in Bermuda, and concluded that their geological setting, sedimentary relations, micropetrography and microfaunal assemblages were inconsistent with sustained intertidal deposition. Instead, we hypothesized that these deposits were the result of a large tsunami that impacted the Bermuda island platform during the mid-Pleistocene. Hearty and Olson [Hearty, P.J., and Olson, S.L., in press. Mega-highstand or megatsunami? Discussion of McMurtry et al. "Elevated marine deposits in Bermuda record a late Quaternary megatsunami": Sedimentary Geology, 200, 155-165, 2007 (Aug. 07). Sedimentary Geol. 200, 155-165.] in their response, attempt to refute our conclusions and claim the deposits to be the result of a +21 m eustatic sea level highstand during marine isotope stage (MIS) 11. In our reply we answer the issues raised by Hearty and Olson [Hearty, P.J., and Olson, S.L., in press. Mega-highstand or megatsunami? Discussion of McMurtry et al. "Elevated marine deposits in Bermuda record a late Quaternary megatsunami": Sedimentary Geology, 200, 155-165, 2007 (Aug. 07). Sedimentary Geol. 200,155-165.] and conclude that the Bermuda deposits do not provide unequivocal evidence of a prolonged +21 m eustatic sea level highstand. Rather, the sediments are more likely the result of a past megatsunami in the North Atlantic basin. (c) 2008 Elsevier B.V. All rights reserved.

Evaluation of cacao (Theobroma cacao L.) clones against seven Colombian isolates of Moniliophthora roreri (Cif.) Evans et al., representing four major genetic groupings of the pathogen in cacao

Artificial pod inoculation was used to compare the relative aggressiveness of seven Colombian isolates of Moniliophthora roreri (the causal agent of moniliasis or frosty pod disease), representing four major genetic groupings of the pathogen in cacao (cocoa), when applied to five diverse cacao genotypes (ICS-1, ICS-95, TSH-565, SCC-61 and CAP-34) at La Suiza Experimental Farm, Santander Department, Colombia. The following variables were evaluated 9 weeks after inoculation of 2- to 3-month-old pods with spore suspensions (1.2 x 10(5) spores mL(-1)): (i) disease incidence (DI); (ii) external severity (ES); and (iii) internal severity (IS). IS was found to be of greatest value in classifying the reaction of the host genotype against M. roreri. Genetic variation reported between isolates and cacao genotypes was not matched by similar diversity in their aggressiveness. All isolates were generally highly aggressive against most cacao genotypes, with only two isolates showing reduced IS and ES reactions. There was considerable variation between clones in the IS and ES scores, but one cultivated clone (ICS-95) displayed a significant level of resistance against all seven isolates. This clone may be useful in cacao breeding initiatives for resistance to moniliasis of cacao.

Theory and practice in value management: a reply to Ellis et al (2005)

The constructivist model of 'soft' value management (VM) is contrasted with the VM discourse appropriated by cost consultants who operate from within UK quantity surveying (QS) practices. The enactment of VM by cost consultants is shaped by the institutional context within which they operate and is not necessarily representative of VM practice per se. Opportunities to perform VM during the formative stages of design are further constrained by the positivistic rhetoric that such practitioners use to conceptualize and promote their services. The complex interplay between VM theory and practice is highlighted and analysed from a non-deterministic perspective. Codified models of 'best practice' are seen to be socially constructed and legitimized through human interaction in the context of interorganizational networks. Published methodologies are seen to inform practice in only a loose and indirect manner, with extensive scope for localized improvization. New insights into the relationship between VM theory and practice are derived from the dramaturgical metaphor. The social reality of VM is seen to be constituted through scripts and performances, both of which are continuously contested across organizational arenas. It is concluded that VM defies universal definition and is conceptualized and enacted differently across different localized contexts.

Reclassification of Bacteroides putredinis (Weinberg et al., 1937) in a New Genus Alistipes gen. nov., as Alistipes putredinis comb. nov., and description of Alistipes finegoldii sp nov., from human sources

During studies on the bacteriology of appendicitis in children, we often isolated from inflamed and non-inflamed tissue samples, an unusual bile-resistant pigment-producing strictly anaerobic gram-negative rod. Phenotypically this organism resembles members of Bacteroides fragilis group of species, as it is resistant to bile and exhibits a special-potency-disk pattern (resistance to vancomycin, kanamycin and colistin) typical for the B. fragilis group. However, the production of brown pigment on media containing haemolysed blood and a cellular fatty acid composition dominated by iso-C15:0, suggests that the organism most closely resembles species of the genus Porphyromonas. However, the unidentified organism differs from porphyromonads by being bile-resistant and by not producing butyrate as a metabolic end-product. Comparative 16S ribosomal RNA gene sequencing studies show the unidentified organism represents a distinct sub-line, associated with but distinct from, the miss-classified species Bacteroides putredinis. The clustering of the unidentified bacterium with Bacteroides putredinis was statistically significant, but they displayed >4% sequence divergence with each other. Chromosomal DNA-DNA pairing studies further confirmed the separateness of the unidentified bacterium and Bacteroides putredinis. Based on phenotypic and phylogenetic considerations, it is proposed that Bacteroides putredinis and the unidentified bacterium from human sources be classified in a new genus Alistipes, as Alistipes putredinis comb. nov. and Alistipes finegoldii sp. nov., respectively. The type strain of Alistipes finegoldii is CCUG 46020(T) (= AHN2437(T)).

Description of Enterococcus canis sp nov from dogs and reclassification of Enterococcus porcinus Teixeira et al. 2001 as a junior synonym of Enterococcus villorum Vancanneyt et al. 2001

Strains from anal swabs and chronic otitis externa in dogs were shown to be phylogenetically related to the Enterococcus faecium species group. They shared a number of phenotypic characteristics with these species, but they could be easily differentiated by biochemical reactions. In addition, the canine strains were unusual in their nearly complete failure to grow on sodium azide-containing enterococci-selective media and in their Voges-Proskauer reactions (usually negative). By using 16S rRNA sequencing and DNA-DNA hybridization of representative strains, as well as tDNA interspacer gene PCR and SDS-PAGE of whole-cell proteins, the group of canine strains was shown to constitute a novel enterococcal species. The name Enterococcus canis sp. nov. is proposed for this species, with LMG 12316(T) (= CCUG 46666(T)) as the type strain. Concurrently, the taxonomic situation and nomenclatural position of Enterococcus porcinus were investigated. As no phenotypic or genotypic differences were found between this species and Enterococcus villorum, the name E. porcinus is considered to be a junior synonym of E. villorum.