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A template for estimating uncertainties (unc.) of measured neutron-induced fission, (n,f), cross-sections (cs) is presented. This preliminary template not only lists all expected unc. sources but also supplies ranges of unc., estimates for correlations between unc. of the same and different experiments which can be used if the information is nonexistent. If this template is applied systematically when estimating experimental covariances for an evaluation, it may help in pinpointing missing unc. for individual datasets, identifying unreasonably low unc., and estimating correlations between different experimental datasets. Thus, a detailed unc. estimate – usually, a time-intensive procedure – can be undertaken more consistently and efficiently. As an example, it is shown that unc. and correlations of 239Pu(n,f) by Merla et al. [Proceedings of the Conference on Nuclear Data for Science and Technology 1991 Jülich (Springer-Verlag, Berlin, 1992) pp. 510–513], which are questionably low in the GMA database underlying the neutron cs standards evaluations, are distinctly larger at 14.7 MeV and more strongly correlated if this template is used for reestimating the associated covariances.

Root exudates play a key role in mediating plant-plant and plant-rhizomicrobiome interactions, including regulating biochemical/physiological aspects of plant-associated microorganisms, to enhance host plant growth and resilience. Root exudates can act as signals to reduce the competition from neighboring plants and recruiting/choreographing a wide range of diverse rhizomicrobiome members to make the host plant a good fit with its immediate environment. Root exudate production is a dynamic and key process, but there is a limited understanding of the metabolites or metabolic pathways involved in the inter-organismal communications facilitated by them. Given the well-known symbiotic relationships between plants and associated rhizomicrobiome members, adding root exudates to microbial isolation media may allow some of the large segments of rhizomicrobiome members that are not currently culturable to be grown in vitro. This will provide new insights into how root signals orchestrate associated microbes, will benefit agricultural production in the face of challenges posed by climate change, and will help to sustainably provide food for a growing global human population. [ABSTRACT FROM AUTHOR]

Agriculture has an important potential role in mitigating greenhouse gas emissions (GHG). However, practices that reduce C[O.sub.2] emissions from soils and increase the soil organic C level may stimulate [N.sub.2]O emissions. This is particularly critical in Quebec where heavy soils and a humid climate may limit the adoption of agricultural practices designed to mitigate GHG. The objective of this work was to study the effects of two tillage and N fertilization regimes on C[O.sub.2] and [N.sub.2]O fluxes and the seasonal variability in emissions of these gases, associated with corn (Zea mays L.) grown in southwestern Quebec. Different seasonal emission patterns of C[O.sub.2] and [N.sub.2]O were observed. Higher [N.sub.2]O fluxes occurred during the spring and were associated with precipitation events, while higher C[O.sub.2] flues occurred in mid-season and were related to temperature. Conventional tillage (CT) had greater peaks of C[O.sub.2] emissions than no-till (NT) only after disking in the spring. Once corn was established, differences between tillage systems were small. Peaks of [N.sub.2]O emission occurred in both systems (NT and CT) following N application. Plots receiving 180 kg N [ha.sup.-1] in both tillage systems had large peak of [N.sub.2]O emission rates during the wettest parts of the season. The CT and NT systems generally had similar cumulative C[O.sub.2] emissions but NT had higher cumulative [N.sub.2]O emissions than CT. Our findings suggests that changing from CT to NT under the heavy soil conditions of Quebec may increase GHG, mainly as result of the increase in [N.sub.2]O emission. This negative effect of NT could be reduced by avoiding fertilizing when precipitation is more intense. Abbreviations: CT, conventional tillage; GHG, greenhouse gas emissions; NT, no-till; WFPS, water-filled pore space.