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David Castonguay Julien Dufort-Gervais Caroline Ménard Manavi Chatterjee Rémi Quirion Bruno Bontempi Jay S. Schneider Amy F.T. Arnsten Angus C. Nairn Christopher M. Norris Guylaine Ferland Erwan Bézard Pierrette Gaudreau Paul J. Lombroso Jonathan Brouillette 《Current biology : CB》2018,28(7):1079-1089.e4
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Lacey J. Hilliard Mary H. Buckingham G. John Geldhof Patricia Gansert Caroline Stack Erin S. Gelgoot 《应用发育科学》2018,22(1):1-13
Video games have the potential to be contexts for moral learning. We investigated whether Quandary, a video game designed to promote ethical thinking and moral considerations for decision-making, would help promote positive skills such as perspective taking and empathy in adolescents. We examined the effect of playing Quandary on 131 middle school students on self-reported measures of moral thinking via mixed-method randomized control trials. In addition, we conducted qualitative analyses of one-on-one participant interviews and short-answer responses to capture experiences and reflections from playing Quandary, as well as the depth in which students across conditions responded to the interview questions. We found that short-term quantitative indicators did not show change across conditions; however, qualitative analyses revealed thematic responses that are consistent with the core components of the Quandary game, and that students in the Quandary condition showed a greater depth of response to interview questions. This work is a first step in exploring the potential for virtual game play on children’s social, emotional, and cognitive development. 相似文献
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Coupling Input‐Output Tables with Macro‐Life Cycle Assessment to Assess Worldwide Impacts of Biofuels Transport Policies 下载免费PDF全文
Audrey Somé Thomas Dandres Caroline Gaudreault Guillaume Majeau‐Bettez Richard Wood Réjean Samson 《Journal of Industrial Ecology》2018,22(4):643-655
Many countries see biofuels as a replacement to fossil fuels to mitigate climate change. Nevertheless, some concerns remain about the overall benefits of biofuels policies. More comprehensive tools seem required to evaluate indirect effects of biofuel policies. This article proposes a method to evaluate large‐scale biofuel policies that is based on life cycle assessment (LCA), environmental extensions of input‐output (I‐O) tables, and a general equilibrium model. The method enables the assessment of indirect environmental effects of biofuels policies, including land‐use changes (LUCs), in the context of economic and demographic growth. The method is illustrated with a case study involving two scenarios. The first one describes the evolution of the world economy from 2006 to 2020 under business as usual (BAU) conditions (including demographic and dietary preferences changes), and the second integrates biofuel policies in the United States and the European Union (EU). Results show that the biofuel scenario, originally designed to mitigate climate change, results in more greenhouse gas emissions when compared to the BAU scenario. This is mainly due to emissions associated with global LUCs. The case study shows that the method enables a broader consideration for environmental effects of biofuel policies than usual LCA: Global economic variations calculated by a general equilibrium economic model and LUC emissions can be evaluated. More work is needed, however, to include new biofuel production technologies and reduce the uncertainty of the method. 相似文献
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The effect of warmer winters on the demography of an outbreak insect is hidden by intraspecific competition 下载免费PDF全文
Devin W. Goodsman Guenchik Grosklos Brian H. Aukema Caroline Whitehouse Katherine P. Bleiker Nate G. McDowell Richard S. Middleton Chonggang Xu 《Global Change Biology》2018,24(8):3620-3628
Warmer climates are predicted to increase bark beetle outbreak frequency, severity, and range. Even in favorable climates, however, outbreaks can decelerate due to resource limitation, which necessitates the inclusion of competition for limited resources in analyses of climatic effects on populations. We evaluated several hypotheses of how climate impacts mountain pine beetle reproduction using an extensive 9‐year dataset, in which nearly 10,000 trees were sampled across a region of approximately 90,000 km2, that was recently invaded by the mountain pine beetle in Alberta, Canada. Our analysis supports the hypothesis of a positive effect of warmer winter temperatures on mountain pine beetle overwinter survival and provides evidence that the increasing trend in minimum winter temperatures over time in North America is an important driver of increased mountain pine beetle reproduction across the region. Although we demonstrate a consistent effect of warmer minimum winter temperatures on mountain pine beetle reproductive rates that is evident at the landscape and regional scales, this effect is overwhelmed by the effect of competition for resources within trees at the site level. Our results suggest that detection of the effects of a warming climate on bark beetle populations at small spatial scales may be difficult without accounting for negative density dependence due to competition for resources. 相似文献
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Multi‐model comparison highlights consistency in predicted effect of warming on a semi‐arid shrub 下载免费PDF全文
Katherine M. Renwick Caroline Curtis Andrew R. Kleinhesselink Daniel Schlaepfer Bethany A. Bradley Cameron L. Aldridge Benjamin Poulter Peter B. Adler 《Global Change Biology》2018,24(1):424-438
A number of modeling approaches have been developed to predict the impacts of climate change on species distributions, performance, and abundance. The stronger the agreement from models that represent different processes and are based on distinct and independent sources of information, the greater the confidence we can have in their predictions. Evaluating the level of confidence is particularly important when predictions are used to guide conservation or restoration decisions. We used a multi‐model approach to predict climate change impacts on big sagebrush (Artemisia tridentata), the dominant plant species on roughly 43 million hectares in the western United States and a key resource for many endemic wildlife species. To evaluate the climate sensitivity of A. tridentata, we developed four predictive models, two based on empirically derived spatial and temporal relationships, and two that applied mechanistic approaches to simulate sagebrush recruitment and growth. This approach enabled us to produce an aggregate index of climate change vulnerability and uncertainty based on the level of agreement between models. Despite large differences in model structure, predictions of sagebrush response to climate change were largely consistent. Performance, as measured by change in cover, growth, or recruitment, was predicted to decrease at the warmest sites, but increase throughout the cooler portions of sagebrush's range. A sensitivity analysis indicated that sagebrush performance responds more strongly to changes in temperature than precipitation. Most of the uncertainty in model predictions reflected variation among the ecological models, raising questions about the reliability of forecasts based on a single modeling approach. Our results highlight the value of a multi‐model approach in forecasting climate change impacts and uncertainties and should help land managers to maximize the value of conservation investments. 相似文献
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Differential roles of glucosinolates and camalexin at different stages of Agrobacterium‐mediated transformation 下载免费PDF全文
Po‐Yuan Shih Shu‐Jen Chou Caroline Müller Barbara Ann Halkier Rosalia Deeken Erh‐Min Lai 《Molecular Plant Pathology》2018,19(8):1956-1970
Agrobacterium tumefaciens is the causal agent of crown gall disease in a wide range of plants via a unique interkingdom DNA transfer from bacterial cells into the plant genome. Agrobacterium tumefaciens is capable of transferring its T‐DNA into different plant parts at different developmental stages for transient and stable transformation. However, the plant genes and mechanisms involved in these transformation processes are not well understood. We used Arabidopsis thaliana Col‐0 seedlings to reveal the gene expression profiles at early time points during Agrobacterium infection. Common and differentially expressed genes were found in shoots and roots. A gene ontology analysis showed that the glucosinolate (GS) biosynthesis pathway was an enriched common response. Strikingly, several genes involved in indole glucosinolate (iGS) modification and the camalexin biosynthesis pathway were up‐regulated, whereas genes in aliphatic glucosinolate (aGS) biosynthesis were generally down‐regulated, on Agrobacterium infection. Thus, we evaluated the impacts of GSs and camalexin during different stages of Agrobacterium‐mediated transformation combining Arabidopsis mutant studies, metabolite profiling and exogenous applications of various GS hydrolysis products or camalexin. The results suggest that the iGS hydrolysis pathway plays an inhibitory role on transformation efficiency in Arabidopsis seedlings at the early infection stage. Later in the Agrobacterium infection process, the accumulation of camalexin is a key factor inhibiting tumour development on Arabidopsis inflorescence stalks. In conclusion, this study reveals the differential roles of GSs and camalexin at different stages of Agrobacterium‐mediated transformation and provides new insights into crown gall disease control and improvement of plant transformation. 相似文献