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Heavy crude oil transportation over land is increasing, yet the ecological impacts of spills, particularly of diluted bitumen, in freshwater environments remain poorly understood. We simulated spills of diluted bitumen in 1400 L land-based mesocosms containing water and sediments from a boreal, oligotrophic lake and monitored the response of natural planktonic communities over 11 days. Most species of phytoplankton (chrysophytes and dinoflagellates) and zooplankton (copepods and cladocerans) were sensitive to oil, exhibiting >70% overall abundance reductions in response to the spills. Declines in nano- and microphytoplankton were short-lived and began to recover after the oil sank, whereas picophytoplankton and zooplankton populations remained depressed at the end of the experiment. In contrast, oil spills stimulated bacteria known to degrade hydrocarbons, especially Alphaproteobacteria, whereas Gammaprotobacteria(a common marine oil spill bacterial class) increased less. This is the first experiment to examine the effects of diluted bitumen in a multitrophic freshwater community. Si le transport terrestre de petrole brut lourd est a la hausse, la comprehension des impacts ecologiques de deversements, particulierement de bitume dilue, dans les milieux d'eau douce demeure limitee. Nous avons simule des deversements de bitume dilue dans des mesocosmes terrestres de 1400 L contenant de l'eau et des sediments d'un lac oligotrophe boreal et surveille les reactions de communautes de plancton naturelles sur une periode de 11 jours. La plupart des especes de phytoplancton (chrysophytes et dinoflagelles) et de zooplancton (copepodes et cladoceres) etaient sensibles a la presence de petrole, presentant des baisses d'abondance globale de >70 % en reaction aux deversements. Les baisses etaient de courte duree en ce qui concerne le nanophytoplancton et le microphytoplancton, et ils commencaient a se remettre une fois le petrole coule au fond, alors que les populations de picophytoplancton et de zooplancton demeuraient reduites a la fin de l'experience. En comparaison, les deversements de petrole stimulaient les bacteries connues pour degrader les hydrocarbures, particulierement les alphaproteobacteries, alors que l'abondance de gammaprotobacteries (une classe repandue de bacteries associees aux deversements de petrole en mer) n'augmentait pas autant. Il s'agit de la premiere experience a examiner les effets du bitume dilue dans une communaute d'eau douce multitrophique. [Traduit par la Redaction], Introduction Heavy crude oils are complex mixtures of organic components and carry additional contaminants, including sulfur, and metals (vanadium, nickel, iron) (Martinez-Palou et al. 2011; ECCC 2013; Lee et al. [...]

This study examines the correlates of creative potential in preschool children, with a focus on children's social behavior. Ninety-four preschool-aged children, their mothers, and teachers participated in the study. Mothers completed a questionnaire measure of children's shyness, and teachers reported on children's levels of shyness, prosocial behavior, and aggression. Children completed Torrance's Thinking Creatively in Action and Movement. Results indicated that imagination was predicted by lower levels of shyness and greater prosocial behavior, whereas divergent thinking was predicted by older child age and teacher ratings of aggression. Implications for promoting young children's creative potential in the classroom are discussed.

The COVID-19 pandemic arrived with significant hardship. The secondary impacts of the pandemic and our response with respect to pediatric mental health has been a subject of significant discussion in the lay public, media, and decision-maker groups. The initiatives to control SARS-CoV-2 have become politicized. A narrative emerged early that strategies to mitigate the spread of the virus were harming children’s mental health. Position statements from professional organizations in Canada have been used to support this claim. The aim of this commentary is to provide a reanalysis of some of the data and research methodology used to support these position statements. Some of the direct claims such as “online learning is harmful,” should be supported by a strong evidence base with significant consensus that speaks directly to causality. We find that the quality of the studies and the heterogeneity of the results does not support the strength of the unequivocal claims made by these position statements. In a sample of the current literature examining the issue, we find that outcomes range from improvements to deteriorations. Earlier studies relying on cross-sectional surveys typically have shown stronger negative effects than longitudinal cohort studies, which often have also shown groups of children experiencing no changes to measured mental health characteristics or groups that have experienced improvements. We argue it is imperative that policymakers use the highest quality evidence in making the best decisions. We as professionals must avoid discussing only one side of heterogeneous evidence. [ABSTRACT FROM AUTHOR]

Telling and dramatizing stories is an increasingly popular addition to the preschool curriculum, largely due to the attention this activity has received through the writings of Vivian Paley (Bad guys don't have birthdays: fantasy play at four. The University of Chicago Press, Chicago, 1988; The boy who would be a helicopter: the uses of storytelling in the kindergarten. Harvard University Press, Cambridge, MA, 1990; A child's work: the importance of fantasy play. The University of Chicago Press, Chicago, 2004). While the writings of Paley and others (Cooper, When stories come to school: telling, writing, and performing stories in the early childhood classroom. Teachers & Writers Collaborative, New York, 1993; Engel 1999) focus on the social and cognitive outcomes children experience as a result of storytelling, less has been written about the process of writing and dramatizing stories with young children. This article discusses procedures and considerations that enhance storytelling with preschool children, including effective prompts for encouraging children's creativity, potential trouble spots such as aggression in stories, and ways that storytelling can enhance home-school relationships.