Large-scale effects of subglacial meltwater flow in the southern Slave Province, Northwest Territories, Canada

2000 ◽  
Vol 37 (1) ◽  
pp. 81-93 ◽  
Author(s):  
V N Rampton
Keyword(s):  
Northwest Territories ◽  
High Velocity ◽  
Large Scale ◽  
High Pressures ◽  
Scale Effects ◽  
Dispersal Patterns ◽  
Slave Province ◽  
Glaciofluvial Deposits ◽  
Gravel Bars ◽  
Subglacial Meltwater

Broad corridors in the southern Slave Province of the Northwest Territories are marked by meltwater-scoured bedrock, irregular and transverse gravel ridges, gravel bars, crag and tail features (tails formed of gravel), drumlins, boulder lags, potholes, plunge pools, meltwater-sculpted slopes (in some cases defining till plateaus), and eskers. Most of the above features can either be attributed to the subglacial erosion of till by high-velocity, turbulent meltwater under high pressures and (or) meltwater transport and deposition of the eroded material. Potholes, plunge pools, and meltwater-sculpted slopes developed in unconsolidated deposits have received little attention in the literature, although they are the equivalent of similar features in bedrock that have had their origin attributed to subglacial meltwater erosion. In the case of inverted plunge pools, eroded materials, including boulders, have been transported upwards by meltwater some tens of metres during their formation. Features and deposits owing their origin to subglacial meltwater can lead to complex dispersal patterns of minerals and metals contained within both till and glaciofluvial deposits.

Late Glacial landforms of Wollaston Peninsula, Victoria Island, Northwest Territories: product of ice-marginal retreat, surge, and mass stagnation

1988 ◽  
Vol 25 (2) ◽  
pp. 262-279 ◽  
Author(s):  
David R. Sharpe
Keyword(s):  
Northwest Territories ◽  
Large Scale ◽  
Regional Scale ◽  
Late Glacial ◽  
Ground Moraine ◽  
Ice Conditions ◽  
Late Wisconsinan ◽  
Victoria Island ◽  
Glacial Landforms ◽  
Subglacial Meltwater

An analysis of glacial landforms on a regional scale leads to an interpretation of the dynamics of Late Wisconsinan glaciation on Wollaston Peninsula, Victoria Island, Northwest Territories. The glacial record is dominated by four adjacent belts of landforms: (I) ground moraine (till plains and ice-marginal drainage features), (II) hummocky moraine, (III) lateral and shear moraine, and (IV) streamlined landforms. The landform belts are considered as representing four distinct glacial ice conditions or regimes: (1) ice-margin retreat during extending flow of thin, active ice; (2) marginal ice stagnation following compressional flow; (3) a surging ice margin producing massive shear moraines; and (4) large-scale flooding and mass ice stagnation following a surge. These landform belts were arranged in zones by topographically controlled glacial dynamics, the latter two defining a former ice stream.Glaciological inferences can be extended by examining the sediments and processes that produced each landform set. Ground-moraine sediments were produced mainly subglacially from melt out or lodgment of glacial debris. Hummocky moraine resulted from debris flow and meltwater deposition controlled by ice, from resedimentation by sediment gravity flow, and from slump. Compressional shearing stacked thick deposits of drift prior to resedimentation. Simple lateral or end moraines may comprise interbedded sediment gravity flows deposited at static ice margins. Deformed lateral moraines resulted from intense marginal compressive flow that sheared and stacked thick, coarse sediment ridges or plates. This lateral shearing may be attributed to streaming or large ice surges. Drumlin exposures showed undeformed, interbedded, stratified sediments that appear to have accumulated in a subglacial cavity; there is no deformation related to high subglacial stress. Subglacial meltwater floods may have followed glacier surge. The greatly extended and thinner ice mass produced by the surge melted in place as clean (debris-free) ice.

Viability of Azure IoT Hub for Processing High Velocity Large Scale IoT Data

2021 ◽  
Author(s):  
Wajdi H. Halabi ◽  
Daniel N. Smith ◽  
John C. Hill ◽  
Jason W. Anderson ◽  
Ken E. Kennedy ◽  
...  
Keyword(s):  
High Velocity ◽  
Large Scale

scholarly journals A non-targeted LC–MS metabolic profiling of pregnancy: longitudinal evidence from healthy and pre-eclamptic pregnancies

Metabolomics ◽  
2021 ◽  
Vol 17 (2) ◽  
Author(s):  
Tiina Jääskeläinen ◽  
◽  
Olli Kärkkäinen ◽  
Jenna Jokkala ◽  
Anton Klåvus ◽  
...  
Keyword(s):  
Large Scale ◽  
Scale Effects ◽  
Late Pregnancy ◽  
Metabolite Profile ◽  
Adverse Outcomes ◽  
Liquid Chromatography Mass Spectrometry ◽  
Targeted Metabolomics ◽  
Serum Samples ◽  
Healthy Women ◽  
Maternal Metabolism

Abstract Introduction Maternal metabolism changes substantially during pregnancy. However, few studies have used metabolomics technologies to characterize changes across gestation. Objectives and methods We applied liquid chromatography–mass spectrometry (LC–MS) based non-targeted metabolomics to determine whether the metabolic profile of serum differs throughout the pregnancy between pre-eclamptic and healthy women in the FINNPEC (Finnish Genetics of Preeclampsia Consortium) Study. Serum samples were available from early and late pregnancy. Results Progression of pregnancy had large-scale effects to the serum metabolite profile. Altogether 50 identified metabolites increased and 49 metabolites decreased when samples of early pregnancy were compared to samples of late pregnancy. The metabolic signatures of pregnancy were largely shared in pre-eclamptic and healthy women, only urea, monoacylglyceride 18:1 and glycerophosphocholine were identified to be increased in the pre-eclamptic women when compared to healthy controls. Conclusions Our study highlights the need of large-scale longitudinal metabolomic studies in non-complicated pregnancies before more detailed understanding of metabolism in adverse outcomes could be provided. Our findings are one of the first steps for a broader metabolic understanding of the physiological changes caused by pregnancy per se.

scholarly journals Glucose-Limited Fed-Batch Cultivation Strategy to Mimic Large-Scale Effects in Escherichia coli Linked to Accumulation of Non-Canonical Branched-Chain Amino Acids by Combination of Pyruvate Pulses and Dissolved Oxygen Limitation

2021 ◽  
Vol 9 (6) ◽  
pp. 1110
Author(s):  
Ángel Córcoles García ◽  
Peter Hauptmann ◽  
Peter Neubauer
Keyword(s):  
Amino Acids ◽  
Dissolved Oxygen ◽  
Large Scale ◽  
Scale Effects ◽  
Branched Chain Amino Acids ◽  
Oxygen Limitation ◽  
Fed Batch ◽  
Fermentation Products ◽  
Cultivation Strategy ◽  
Branched Chain

Insufficient mixing in large-scale bioreactors provokes gradient zones of substrate, dissolved oxygen (DO), pH, and other parameters. E. coli responds to a high glucose, low oxygen feeding zone with the accumulation of mixed acid fermentation products, especially formate, but also with the synthesis of non-canonical amino acids, such as norvaline, norleucine and β-methylnorleucine. These amino acids can be mis-incorporated into recombinant products, which causes a problem for pharmaceutical production whose solution is not trivial. While these effects can also be observed in scale down bioreactor systems, these are challenging to operate. Especially the high-throughput screening of clone libraries is not easy, as fed-batch cultivations would need to be controlled via repeated glucose pulses with simultaneous oxygen limitation, as has been demonstrated in well controlled robotic systems. Here we show that not only glucose pulses in combination with oxygen limitation can provoke the synthesis of these non-canonical branched-chain amino acids (ncBCAA), but also that pyruvate pulses produce the same effect. Therefore, we combined the enzyme-based glucose delivery method Enbase® in a PALL24 mini-bioreactor system and combined repeated pyruvate pulses with simultaneous reduction of the aeration rate. These cultivation conditions produced an increase in the non-canonical branched chain amino acids norvaline and norleucine in both the intracellular soluble protein and inclusion body fractions with mini-proinsulin as an example product, and this effect was verified in a 15 L stirred tank bioreactor (STR). To our opinion this cultivation strategy is easy to apply for the screening of strain libraries under standard laboratory conditions if no complex robotic and well controlled parallel cultivation devices are available.

Grabbing Life by the Ballot: Creating an Effective Ballot through Design

2020 ◽  
Author(s):  
Katharine McCoy
Keyword(s):  
Product Design ◽  
Design Process ◽  
Large Scale ◽  
Scale Effects ◽  
The World ◽  
Ballot Design ◽  
The Government ◽  
Democratic Elections ◽  
Effective Design ◽  
Undergraduate Thesis

This presentation, reflecting a politics undergraduate thesis, will explore the design process behind the ballots that voters use in democratic elections around the world. Ballots are an inherently political objects, and in many cases, the most direct line of communication a citizen has to the government of their country. As such, the design of the ballot affects the legitimacy of higher level electoral and democratic institutions. This project argues that by co-opting the language of product design, a universal ballot design process would make more efficient ballots across the globe.   Product design starts with a brainstorming stage that explores at the user, the goal of the object, and the context of its use to create an effective design. By applying these observations to the process of designing a ballot, each electoral commission can produce a more effective ballot. Currently there is no standardization for ballot design other than ensuring that electoral commissions tried to make it “friendly.” By examining cases of bad ballot design, it is possible to see what element of the design process was missed or misused to create a process that corrects for these mistakes. This project examines poorly designed ballots in Florida, Scotland, and Colombia to explore the large-scale effects these small design choices make, and how to fix them. 

scholarly journals Fungarium specimens: a largely untapped source in global change biology and beyond

2018 ◽  
Vol 374 (1763) ◽  
pp. 20170392 ◽  
Author(s):  
Carrie Andrew ◽  
Jeffrey Diez ◽  
Timothy Y. James ◽  
Håvard Kauserud
Keyword(s):  
Global Change ◽  
Dna Sequences ◽  
Large Scale ◽  
Dna Analysis ◽  
Sampling Location ◽  
Sources Of Information ◽  
Dispersal Patterns ◽  
Global Change Biology ◽  
Richness Patterns ◽  
Collection Date

For several hundred years, millions of fungal sporocarps have been collected and deposited in worldwide collections (fungaria) to support fungal taxonomy. Owing to large-scale digitization programs, metadata associated with the records are now becoming publicly available, including information on taxonomy, sampling location, collection date and habitat/substrate information. This metadata, as well as data extracted from the physical fungarium specimens themselves, such as DNA sequences and biochemical characteristics, provide a rich source of information not only for taxonomy but also for other lines of biological inquiry. Here, we highlight and discuss how this information can be used to investigate emerging topics in fungal global change biology and beyond. Fungarium data are a prime source of knowledge on fungal distributions and richness patterns, and for assessing red-listed and invasive species. Information on collection dates has been used to investigate shifts in fungal distributions as well as phenology of sporocarp emergence in response to climate change. In addition to providing material for taxonomy and systematics, DNA sequences derived from the physical specimens provide information about fungal demography, dispersal patterns, and are emerging as a source of genomic data. As DNA analysis technologies develop further, the importance of fungarium specimens as easily accessible sources of information will likely continue to grow. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the Anthropocene’.

scholarly journals Why the Slave Province, Northwest Territories, got a little bigger

2000 ◽  
Author(s):  
W Bleeker ◽  
R Stern ◽  
K Sircombe
Keyword(s):  
Northwest Territories ◽  
Slave Province

scholarly journals A Review of the Canada Petroleum Resources Act and the Canada Oil and Gas Operations Act as the Legal Framework for Future Development in the Northwest Territories

2002 ◽  
Vol 40 (1) ◽  
pp. 83
Author(s):  
Raymond E. Quesnel
Keyword(s):  
Northwest Territories ◽  
Large Scale ◽  
Oil And Gas ◽  
East Coast ◽  
Historical Analysis ◽  
Legal Framework ◽  
Tenure System ◽  
Petroleum Resources ◽  
Legislative Framework ◽  
Oil And Gas Operations

This article examines the current core legislation that governs oil and gas activity in Canada's North. While there has been increased industry interest in the Northwest Territories, there has thus far been a lack of actual oil and gas projects against which to measure the efficacy of the current regime in the context of northern development. An historical analysis of the legislative developments indicates that the northern regime formed the basis for the legislative framework now governing east coast megaprojects. The author evaluates the current basis on which rights are granted and recorded, the tenure system, the royalty regime, and the project approval process. He concludes that, while the northern regime is suitable for large scale developments, it may require certain changes to accommodate smaller, more conventional projects likely to be undertaken.

scholarly journals Large-scale integrated subglacial drainage around the former Keewatin Ice Divide, Canada reveals interaction between distributed and channelised systems

2020 ◽  
Author(s):  
Emma L. M. Lewington ◽  
Stephen J. Livingstone ◽  
Chris D. Clark ◽  
Andrew J. Sole ◽  
Robert D. Storrar
Keyword(s):  
Spatial Distribution ◽  
Dynamic Response ◽  
Large Scale ◽  
Water Pressure ◽  
Pressure Fluctuations ◽  
Drainage System ◽  
Different Types ◽  
Form Part ◽  
Subglacial Meltwater ◽  
Subglacial Drainage

Abstract. We identify and map traces of subglacial meltwater drainage around the former Keewatin Ice Divide, Canada from ArcticDEM data. Meltwater tracks, tunnel valleys and esker splays exhibit several key similarities, including width, spacing, their association with eskers and transitions to and from different types, which together suggest they form part of an integrated drainage signature. We collectively term these features 'meltwater corridors' and propose a new model for their formation, based on observations from contemporary ice masses, of pressure fluctuations surrounding a central conduit. We suggest that eskers record the imprint of a central conduit and meltwater corridors the interaction with the surrounding distributed drainage system. The widespread aerial coverage of meltwater corridors (5–36 % of the bed) provides constraints on the extent of basal uncoupling induced by basal water pressure fluctuations and variations in spatial distribution and evolution of the subglacial drainage system, which will modulate the ice dynamic response.

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