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The only Canadian inventory of natural source emissions of mercury (Hg) was prepared in 1981, but is now considered unreliable. As a result, the primary reference relied upon by Canadian regulators concerning the relative contribution of natural sources to environmental Hg contamination is a global inventory that was published in 1989. The relevance to Canada of a global inventory that included volcanic emissions is questionable. Therefore, a new inventory of natural Hg emissions in Canada was undertaken. Consistent with earlier inventories, natural Hg emission sources included wind erosion of soil, sea salt spray, forest and brush fires, biogenic Hg vapour emissions from terrestrial vegetation, and evasion of vapour from soil, ocean surfaces (within territorial limits) and lakes and rivers. Meteoritic dust was also considered. Recognizing the variability and uncertainty in available data, probabilistic methods were employed to derive mean estimates with 90% confidence limits. Estimated total annual natural source emissions of Hg in Canada averaged 1.1×106kg with lower and upper 90% confidence limits of 0.54 × 106and 2.3 × 106kg. Evasion of Hg vapour from terrestrial vegetation and evasion from soil predominated as natural sources of Hg in Canada; other sources were minor or insignificant. The estimated mean annual emission was approximately one third of that estimated in 1981. It was impossible with currently-available data to quantitatively differentiate natural emissions of Hg from those that are re-emitted following previous anthropogenic release and deposition. Therefore, the estimates provided herein include an unquantifiable contribution by re-emitted anthropogenic Hg.

A widely recognized biological characteristic of a healthy and sustainable environment is diversity—as with biology, so with geology. Regions characterized by the presence of different bedrock units, and different surficial materials in areas affected by recent (geologically speaking) glaciation, develop varied landscapes that support differing ecosystems. Examples of varied landscapes range from Alpine and Cordilleran mountains, through gentler landscapes of rolling hills, to the glacial plains of Northern Europe and North America, or similarly from the high Himalayas, through verdant foothills, across fertile plains to the desert of Sind. In the parts of the world characterized by stable geological platforms, where mountain building has not taken place for many hundreds of millions of years and there have been long periods of landscape development, peneplains are the eventual outcome. Their topography is gentle without mountains. High relief areas are largely limited to inselbergs or ravines and river valleys where, due to crustal uplift, modern rivers and streams are cutting down into and eroding the old land surfaces. Examples are the Brasilian Shield, central Australia and parts of central Africa, though in the latter young volcanoes lead to local mountainous terrain. These are the physical expressions of the underlying geology, but there is another changing characteristic that cannot be seen directly—the chemistry of the underlying rocks and sediments and the soils that lie upon them.

This chapter contains sections titled: Introduction Study area Sample design Sample preparation and chemical analysis Results and discussion Conclusions Acknowledgements References

The mammalian Pcdhg gene cluster encodes a family of 22 cell adhesion molecules, the gamma-Protocadherins (γ-Pcdhs), critical for neuronal survival and neural circuit formation. The extent to which isoform diversity-a γ-Pcdh hallmark-is required for their functions remains unclear. We used a CRISPR/Cas9 approach to reduce isoform diversity, targeting each Pcdhg variable exon with pooled sgRNAs to generate an allelic series of 26 mouse lines with 1 to 21 isoforms disrupted via discrete indels at guide sites and/or larger deletions/rearrangements. Analysis of 5 mutant lines indicates that postnatal viability and neuronal survival do not require isoform diversity. Surprisingly, given reports that it might not independently engage in trans-interactions, we find that γC4, encoded by Pcdhgc4, is the only critical isoform. Because the human orthologue is the only PCDHG gene constrained in humans, our results indicate a conserved γC4 function that likely involves distinct molecular mechanisms.

Corporations with attractive core business prospects focus their attention on those core businesses and away from ICVs they may be pursuing, thus influencing how those ICVs are treated from a corporate parenting perspective and, in turn, how well they perform. Using data collected from 145 ICVs operating in 72 corporate parents, this research reveals that corporations with more attractive core businesses grant greater planning autonomy to their ICVs’ managers, and planning autonomy contributes to ICV performance. Additional results reveal the moderating effects within our structural model of venture manager experience and the similarity of the ICV’s product to those of other businesses within the corporation. Considered collectively, this research demonstrates why corporations that “need” their ICVs to be successful – because of poor prospects in their core businesses – are most likely to mismanage them. Unattractive core business prospects can be viewed as justifying corporate managers’ involvement in the direct management of their firms’ ICVs. However, venture planning autonomy is needed to avoid placing undue expectations on ICVs as the “saviors” of corporate performance. By extension, this need for autonomy is also anticipated to apply to other entrepreneurial contexts where experimentation and learning are significant concerns (e.g., business incubators, corporate venture capital investments, new venture divisions).Plain English SummaryThis research demonstrates how and why corporations that have attractive core business operations are most likely to be good corporate parents to their internal corporate ventures (ICVs), and vice versa. In a sense, when it comes to internal corporate venturing, “the rich corporations get richer, and the poor corporations get poorer.” Parent corporations with more attractive core business prospects were found to grant greater planning autonomy to the managers of their ICVs, and autonomy is needed to give ICV managers the discretion and flexibility they need when navigating their ventures though unchartered business territory. Overall, this research demonstrates the importance of corporate managers (1) granting ICV managers autonomy in planning their venture operations, (2) being willing to consider engaging in internal corporate venturing even though their firms’ existing, core business operations may be attractive (i.e., before these ICVs “need” to be successful), and (3) not putting too much pressure on ICVs to “perform,” and avoiding meddling in the management of those ventures, when prospects in the corporation’s core business are unattractive. We argue that autonomy is likely efficacious in most entrepreneurial contexts where experimentation and learning are significant concerns (e.g., business incubators, corporate venture capital investments, new venture divisions).

Numerous bark- and wood-infesting insects have been introduced to new countries by international trade where some have caused severe environmental and economic damage. Wood packaging material (WPM), such as pallets, is one of the high risk pathways for the introduction of wood pests. International recognition of this risk resulted in adoption of International Standards for Phytosanitary Measures No. 15 (ISPM15) in 2002, which provides treatment standards for WPM used in international trade. ISPM15 was originally developed by members of the International Plant Protection Convention to \"practically eliminate\" the risk of international transport of most bark and wood pests via WPM. The United States (US) implemented ISPM15 in three phases during 2005-2006. We compared pest interception rates of WPM inspected at US ports before and after US implementation of ISPM15 using the US Department of Agriculture AQIM (Agriculture Quarantine Inspection Monitoring) database. Analyses of records from 2003-2009 indicated that WPM infestation rates declined 36-52% following ISPM15 implementation, with results varying in statistical significance depending on the selected starting parameters. Power analyses of the AQIM data indicated there was at least a 95% chance of detecting a statistically significant reduction in infestation rates if they dropped by 90% post-ISPM15, but the probability fell as the impact of ISPM15 lessened. We discuss several factors that could have reduced the apparent impact of ISPM15 on lowering WPM infestation levels, and suggest ways that ISPM15 could be improved. The paucity of international interception data impeded our ability to conduct more thorough analyses of the impact of ISPM15, and demonstrates the need for well-planned sampling programs before and after implementation of major phytosanitary policies so that their effectiveness can be assessed. We also present summary data for bark- and wood-boring insects intercepted on WPM at US ports during 1984-2008.

The Heisenberg uncertainty principle states that the position of an object cannot be known with infinite precision, as the momentum of the object would then be totally uncertain. This momentum uncertainty then leads to position uncertainty in future measurements. When continuously measuring the position of an object, this quantum effect, known as back-action, limits the achievable precision1,2. In audio-band, interferometer-type gravitational-wave detectors, this back-action effect manifests as quantum radiation pressure noise (QRPN) and will ultimately (but does not yet) limit sensitivity3. Here, we present the use of a quantum engineered state of light to directly manipulate this quantum back-action in a system where it dominates the sensitivity in the 10–50 kHz range. We observe a reduction of 1.2 dB in the quantum back-action noise. This experiment is a crucial step in realizing QRPN reduction for future interferometric gravitational-wave detectors and improving their sensitivity.

Theory and research typically suggest that internal corporate (ICV) venture managers should be granted the freedom needed to manage their new business initiatives as they choose, with little or no interference from senior levels of corporate management. The current research investigates the relationship between venture planning autonomy and venture performance, arguing that this relationship is affected by the types (i.e., goal related or value proposition related) and levels (low-to-high) of strategic evolution occurring in the ICV. Data collected from 145 ICVs operating in 72 corporations indicate that venture planning autonomy is most positively related to venture performance when those ICVs’ goals remain stable over the course of venture operations, but the value propositions of those ICVs are evolving.