A Summary of gold fineness values from Alaska placer deposits

This report is the first in a series of publications by the Mineral Industry Research Laboratory and the Alaska Division of Geological and Geophysical Surveys under a special appropriation by the Alaska State Legislature to the School of Mineral Industry to conduct a "Mineral Appraisal of Interior Alaska Mining Districts".Funding for the report was supplimented by a grant under the Mining and Mineral Resources Research Institute, Office of Surface Mining, U.S. Department of Interior

MultiCellDS : a community-developed standard for curating microenvironment-dependent multicellular data

Exchanging and understanding scientific data and their context represents a significant barrier to advancing research, especially with respect to information siloing. Maintaining information provenance and providing data curation and quality control help overcome common concerns and barriers to the effective sharing of scientific data. To address these problems in and the unique challenges of multicellular systems, we assembled a panel composed of investigators from several disciplines to create the MultiCellular Data Standard (MultiCellDS) with a use-case driven development process. The standard includes (1) digital cell lines, which are analogous to traditional biological cell lines, to record metadata, cellular microenvironment, and cellular phenotype variables of a biological cell line, (2) digital snapshots to consistently record simulation, experimental, and clinical data for multicellular systems, and (3) collections that can logically group digital cell lines and snapshots. We have created a MultiCellular DataBase (MultiCellDB) to store digital snapshots and the 200+ digital cell lines we have generated. MultiCellDS, by having a fixed standard, enables discoverability, extensibility, maintainability, searchability, and sustainability of data, creating biological applicability and clinical utility that permits us to identify upcoming challenges to uplift biology and strategies and therapies for improving human health

MultiCellDS: a standard and a community for sharing multicellular data

Cell biology is increasingly focused on cellular heterogeneity and multicellular systems. To make the fullest use of experimental, clinical, and computational efforts, we need standardized data formats, community-curated "public data libraries", and tools to combine and analyze shared data. To address these needs, our multidisciplinary community created MultiCellDS (MultiCellular Data Standard): an extensible standard, a library of digital cell lines and tissue snapshots, and support software. With the help of experimentalists, clinicians, modelers, and data and library scientists, we can grow this seed into a community-owned ecosystem of shared data and tools, to the benefit of basic science, engineering, and human health

Cosmological Applications of Gravitational Lensing

The last decade has seen an enormous increase of activity in the field of gravitational lensing, mainly driven by improvements of observational capabilities. I will review the basics of gravitational lens theory, just enough to understand the rest of this contribution, and will then concentrate on several of the main applications in cosmology. Cluster lensing, and weak lensing, will constitute the main part of this review.Comment: 26 pages, including 2 figures (a third figure can be obtained from the author by request) gziped and uuencoded postscript file; to be published in Proceedings of the Laredo Advanced Summer School, Sept. 9

A Retrospective Study of Spatial and Temporal Recruitment Dynamics of Spruce in a Boreal Mixedwood Forest of BC

Understanding post fire white spruce recruitment and natural regeneration in mixed aspen spruce stands in the boreal forests of Northeast British Columbia has proved difficult. Proximity to seed source is generally considered to have one of the greatest influences on natural regeneration of these forests following disturbance by fire. In order to increase our understanding of the dynamics of recruitment following fire, we measured white spruce regeneration within a 59 year old aspen spruce stand in Northeast BC. One meter wide linear transects, 75 m in length, were established perpendicular to the forest edge seed source: three transects were oriented to the southeast and three were oriented to the west (into prevailing wind). The number of white spruce encountered along transects were counted at one meter intervals along each transect. Remnants and co-dominant spruce trees producing seed within a tree length distance (25m) of transects were identified to establish internal stand seed sources. No post fire internal spruce seed sources were detected near transects. White spruce regeneration declined with distance from the fire edge for both sampling orientations. Seedling recruitment was negatively correlated to the direction of the prevailing winds. This resulted in more spruce recruitment on the eastern edge of the stand than the western. However remnants of the original stand or germinant seedlings that maintained co-dominance in the regenerating stand may have contributed spruce seed resulting in internal recruitment. This would result in isolated internal patches of white spruce with densities similar to those found at the forest edge. White spruce seed sources external and internal to the regenerating spruce aspen stand contribute to observed stand dynamics and succession processes. The recruitment and regeneration of spruce in these stands determines the complex nature (species and structural), spatially and temporally, of mixed aspen white spruce stands in Northeast BC

Aftermath of Mountain Pine Beetle Outbreak in British Columbia: Stand Dynamics, Management Response and Ecosystem Resilience

The mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) has infested and killed millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm) forests in British Columbia, Canada, over the past decade. It is now spreading out of its native range into the Canadian boreal forest, with unknown social, economic and ecological consequences. This review explores the ramifications of the MPB epidemic with respect to mid-term timber supply, forest growth, structure and composition, vegetation diversity, forest fire, climate change, and ecosystem resilience. Research confirms that, in British Columbia, all of these variables are more significantly impacted when salvage logging is used as management response to the outbreak. We conclude that appropriate management in response to MPB is essential to ensuring ecologically resilient future forests and reliable mid-term timber supplies for affected human communities. We highlight knowledge gaps and avenues for research to advance our understanding in support of sustainable post-disturbance forest management policies in British Columbia and elsewhere.Other UBCNon UBCReviewedFacult