74 research outputs found
Attracting and retaining science students
"La prĂ©sente recherche a Ă©tĂ© subventionnĂ©e par le ministĂšre de l'Ăducation, du Loisir et du Sport dans le cadre du Programme d'aide Ă la recherche sur l'enseignement et l'apprentissage (PAREA)"Titre de l'Ă©cran-titre (visionnĂ© le 15 mars 2010)Ăgalement disponible en format papier.Bibliogr
L'Ă©cart entre les sexes dans les Ă©tudes en sciences : une question de style cognitif et non d'aptitude cognitive
Comme toile de fond, cet article avance que le nombre infĂ©rieur des femmes, comparativement Ă celui des hommes, qui choisissent de poursuivre des Ă©tudes en sciences, en technologie, en gĂ©nie et en mathĂ©matiques (STGM) serait plus imputable Ă un Ă©cart dans les styles cognitifs plutĂŽt qu'aux aptitudes cognitives. Ă partir d'un sous-ensemble de rĂ©sultats tirĂ©s dâune Ă©tude PAREA, qui examinait plusieurs facteurs (dont la culture, lâaptitude cognitive et le soutien du professeur) pouvant influer sur le choix dâune carriĂšre en STGM et portant sur des Ă©tudiants quĂ©bĂ©cois et suĂ©dois, les auteurs dĂ©montrent comment les styles cognitifs influent sur le succĂšs et la persĂ©vĂ©rance des Ă©tudiants. Ils suggĂšrent aussi des mĂ©thodes pour que les professeurs utilisent les rĂ©sultats de l'Ă©tude afin dâamĂ©liorer la rĂ©ussite de leurs Ă©tudiants et indiquent que leurs conclusions peuvent avoir des rĂ©percussions non seulement sur lâenseignement des STGM, mais aussi dans des domaines tels que la psychologie, la mĂ©thodologie quantitative, lâĂ©conomie et le programme Techniques dâĂ©ducation Ă lâenfance
Just computer aided instruction is not enough combining webwork with in-class interactive sessions increases achievement and perseverance of social science calculus students /
Titre de l'Ă©cran-titre (visionnĂ© le 24 nov. 2008).Ăgalement disponible en format papier.Bibliogr
The puzzling reliability of the Force Concept Inventory
The Force Concept Inventory (FCI) has influenced the development of many research-based pedagogies. However, no data exists on the FCIâs internal consistency or test-retest reliability. The FCI was administered twice to one hundred students during the first week of classes in an electricity and magnetism course with no review of mechanics between test administrations. High KuderâRichardson reliability coefficient values, which estimate the average correlation of scores obtained on all possible halves of the test, suggest strong internal consistency. However, 31% of the responses changed from test to retest, suggesting weak reliability for individual questions. A chi-square analysis shows that change in responses was neither consistent nor completely random. The puzzling conclusion is that although individual FCI responses are not reliable, the FCI total score is highly reliable
Discovery of a Gas-Rich Companion to the Extremely Metal-Poor Galaxy DDO 68
We present HI spectral-line imaging of the extremely metal-poor galaxy DDO
68. This system has a nebular oxygen abundance of only 3% Z, making
it one of the most metal-deficient galaxies known in the local volume.
Surprisingly, DDO 68 is a relatively massive and luminous galaxy for its metal
content, making it a significant outlier in the mass-metallicity and
luminosity-metallicity relationships. The origin of such a low oxygen abundance
in DDO 68 presents a challenge for models of the chemical evolution of
galaxies. One possible solution to this problem is the infall of pristine
neutral gas, potentially initiated during a gravitational interaction. Using
archival HI spectral-line imaging obtained with the Karl G. Jansky Very Large
Array, we have discovered a previously unknown companion of DDO 68. This
low-mass (M 2.810 M), recently
star-forming (SFR 1.410 M yr,
SFR 710 M yr) companion has
the same systemic velocity as DDO 68 (V 506 km s; D
12.740.27 Mpc) and is located at a projected distance of 42 kpc. New HI
maps obtained with the 100m Robert C. Byrd Green Bank Telescope provide
evidence that DDO 68 and this companion are gravitationally interacting at the
present time. Low surface brightness HI gas forms a bridge between these
objects.Comment: Accepted for publication in the Astrophysical Journal Letter
Scaling up socio-technological pedagogies what does it take to develop students' learning and teachers, expertise in innovative environments ? /
La prĂ©sente recherche a Ă©tĂ© subventionnĂ©e par le ministĂšre de l'Ăducation, du Loisir et du Sport dans le cadre du Programme d'aide Ă la recherche sur l'enseignement et l'apprentissage (PAREA)PA-2009-005Ăgalement disponible en version papier.Titre de l'Ă©cran-titre (visionnĂ© le 24 nov. 2011
Wood traits explain microbial but not termiteâdriven decay in Australian tropical rainforest and savanna
1. Variation in decay rates across woody species is a key uncertainty in predicting the fate of carbon stored in deadwood, especially in the tropics. Quantifying the relative contributions of biotic decay agents, particularly microbes and termites, under different climates and across species with diverse wood traits could help explain this variation.
2. To fill this knowledge gap, we deployed woody stems from 16 plant species native to either rainforest (n = 10) or savanna (n = 6) in northeast Australia, with and without termite access. For comparison, we also deployed standardized, non-native pine blocks at both sites. We hypothesized that termites would increase rates of deadwood decay under conditions that limit microbial activity. Specifically, termite contributions to wood decay should be greater under dry conditions and in wood species with traits that constrain microbial decomposers.
3. Termite discovery of stems was surprisingly low with only 17.6% and 22.6% of accessible native stems discovered in the rainforest and savanna respectively. Contrary to our hypothesis, stems discovered by termites decomposed faster only in the rainforest. Termites discovered and decayed pine blocks at higher rates than native stems in both the rainforest and savanna. 4. We found significant variation in termite discovery and microbial decay rates across native wood species within the same site. Although wood traits explained 85% of the variation in microbial decay, they did not explain termite-driven decay. For stems undiscovered by termites, decay rates were greater in species with higher wood nutrient concentrations and syringyl:guiacyl lignin ratios but lower carbon concentrations and wood densities.
5. Synthesis. Ecosystem-scale predictions of deadwood turnover and carbon storage should account for the impact of wood traits on decomposer communities. In tropical Australia, termite-driven decay was lower than expected for native wood on the ground. Even if termites are present, they may not always increase decomposition rates of fallen native wood in tropical forests. Our study shows how the drivers of wood decay differ between Australian tropical rainforest and savanna; further research should test whether such differences apply world-wide
- âŠ