North Canadian Research Articles

Millennial-aged pyrogenic carbon in high-latitude mineral soils

Wildfires in the Arctic are producing pyrogenic carbon as product of incomplete biomass combustion. The storage and distribution of pyrogenic carbon in soils is poorly known, especially in carbon rich permafrost-affected mineral soils. Here, we extracted pyrogenic carbon in mineral soils from eleven forest sites across the North Canadian permafrost regions by hydrogen pyrolysis. We found pyrogenic carbon with millennial-scale ages that were older in continuous (1960–12,690 calibrated years before present) than in discontinuous (510–3560 calibrated years before present) permafrost-affected soils. In all cases, pyrogenic carbon showed longer residence times compared to bulk soil organic carbon. The proportions of pyrogenic carbon on total soil organic carbon were consistent at 6.9 ± 0.5% of total soil organic carbon. Thus, pyrogenic carbon forms a significant component of the total soil organic carbon and climatic as well as soil factors control the long residence times of pyrogenic carbon in vulnerable high-latitude forest mineral soils.

Framework for design and optimization of a retrofitted light industrial space with a renewable energy-assisted hydroponics facility in a rural northern canadian community

The purpose of this study is to develop a design framework for retrofitting a light industrial building with a hybrid renewable energy-assisted hydroponics farming system for production of fresh food in rural north Canadian communities. This design protocol is targeted at facilities in rural areas of northern Canada, which could benefit from better access to fresh food, especially given the harsh climate as well as the long and limited transport routes. The process includes 1) a review of the existing building; 2) estimation of design loads for system sizing, such as temperature and humidity control, adequate lighting, airborne carbon, and water; 3) multi-objective genetic algorithm optimization of the hybrid renewable energy system for minimal operating cost and emissions; and 4) comparison of costs and greenhouse (GHG) emissions of the proposed farming operation with the traditional food supply chain. To demonstrate the proposed methodology, a case study building in a rural community in Alberta, Canada was evaluated for retrofit. The results showed that the GHG emissions generated from local hydroponic lettuce production, aided by a hybrid renewable energy system (HRES), are three times greater than those emitted by transporting an equivalent quantity of food from southern California, USA. On the other hand, the life cycle cost showed that the cost to produce lettuce from the case study facility is comparable to the price of lettuce available from traditional import, which shows a promising potential to provide fresh and cost-competitive food in the community, among other qualitative benefits gained from this empowering opportunity.

Feasibility of PV Integrated Microgrids in Remote North Canadian Communities.

In this paper a methodology for a transition away from a fossil fuel dependency to clean energy in remote communities in northern Canada is presented. Both technical and non-technical obstacles associated with such a transition to clean energy are outlined. A proposal on how to possibly overcome these obstacles is also presented. The technical aspect of this work includes a case study on one of the communities in northern Manitoba, Canada. The case study is supported by simulations, using the software tool PSCADTM/EMTDCTM. The simulation result illustrates how the control system coordinates various parts of a microgrid and reduces annual diesel consumption.

Concrete block structural masonry beam shear design: theoretical and experimental analysis and recommendations to the brazilian standards

Abstract Beams are subject a flexure and shear, with the last as the theme of this research. The purpose of this paper is to analyze specifications for the shear design of concrete block structural masonry beams, based on an extensive literature review and experimental tests here reported. From this scope, specifications for revision of Brazilian standardization are suggested. In the theoretical part, literature review from both national and international researchers were considered and the specifications of Brazilian standards, in addition to North American, Australian, Canadian and European, ABNT NBR 15961-1/2011, ABNT NBR 6118/2014TMS 402/2016, AS3700/2001, CSA S304/2014 and EuroCode6.1/2001, respectively. To analyze and validate the specifications of the literature, an experimental program was carried out assessing ten concrete block masonry beams results tested mainly to shear loads. Two-course high beams with three vertical load positions (position a/d) and two transverse reinforcement rates were tested. The specifications from the Brazilian and European standards led to considerably higher results than the experimental results, while those presented in the standards TMS 402/2016, AS3700/2001, CSA S304/2014 and NBR6118/2014 lead to results close to those obtained experimentally. As a conclusion, it can be noted that the rupture pattern is similar to that expected for reinforced concrete beams, the cracks were conditioned by the position of the loading point and by the mortar joints positions, the increase in the transverse reinforcement ratio led to an increase in the shear force. Results indicate that the consideration of apparent increase in shear strength by the ratio M ⁄ (V∙d) is not consistent. Eliminating this recommendation, considering the masonry shear strength equal to 0.35 MPa, limiting the stirrups tension to 0.90 of fyk and considering the contribution of the longitudinal reinforcement, it was possible to estimate the shear value at the rupture of each beam between 73% to 106% of the values verified in the tests.

Impact of Eastern redcedar encroachment on stream discharge in the North Canadian River basin

Eastern redcedar (<i>Juniperus virginiana</i> L.) is a woody plant that is rapidly encroaching into the grasslands of states located in the US Great Plains. There is some concern that redcedar will adversely impact stream discharge in these water-limited areas through increased transpiration and canopy interception in comparison to that of grasslands. We conducted a modeling study in the central reach of the North Canadian River basin between Lake Canton and Lake Overholser, located in central Oklahoma. The North Canadian River supplies about 25% of Oklahoma City9s water supply. After model calibration, we simulated redcedar encroachment into the study area9s grasslands in 10% increments to assess impact on stream discharge. We also performed simulations that represented complete removal of redcedar from the study area. Our simulations suggested that if all grasslands in the study area were replaced by redcedar, the simulated reduction in stream discharge would equal 112% of current municipal water demand and 89% of the projected 2060 demand. However, a more realistic conversion of 20% of grassland to redcedar would, according to our simulations, reduce stream discharge by an amount of water equivalent to ≈ 27% of the current water demand, or ≈ 21% of the projected 2060 demand. Our model simulations suggest that encroachment of redcedar into grasslands could have a detrimental effect on stream discharge, which could impact water availability on populations further downstream.

Regional characteristics of sea ice thickness in Canadian shelf and Arctic Archipelago measured by Ground Penetrating Radar

Ground Penetrating Radar (GPR) measurements of sea ice thickness including undeformed ice and ridged ice were carried out in the central north Canadian Archipelago in spring 2010. Results have shown a significant spatial heterogeneity of sea ice thickness across the shelf. The undeformed multi-year fast ice of (2.05±0.09) m thick was investigated southern inshore zone of Borden island located at middle of the observational section, which was the observed maximum thickness in the field work. The less thick sea ice was sampled across a flaw lead with the thicknesses of (1.05±0.11) m for the pack ice and (1.24±0.13) m for the fast ice. At the northernmost spot of the section, the undeformed multi-year pack ice was (1.54±0.22) m thick with a ridged ice of 2.5 to 3 m, comparing to the multi-year fast ice with the thickness of (1.67±0.16) m at the southernmost station in the Prince Gustaf Adolf Sea.

Interacting effects of discharge and channel morphology on transport of semibuoyant fish eggs in large, altered river systems.

Habitat fragmentation and flow regulation are significant factors related to the decline and extinction of freshwater biota. Pelagic-broadcast spawning cyprinids require moving water and some length of unfragmented stream to complete their life cycle. However, it is unknown how discharge and habitat features interact at multiple spatial scales to alter the transport of semi-buoyant fish eggs. Our objective was to assess the relationship between downstream drift of semi-buoyant egg surrogates (gellan beads) and discharge and habitat complexity. We quantified transport time of a known quantity of beads using 2–3 sampling devices at each of seven locations on the North Canadian and Canadian rivers. Transport time was assessed based on median capture time (time at which 50% of beads were captured) and sampling period (time period when 2.5% and 97.5% of beads were captured). Habitat complexity was assessed by calculating width∶depth ratios at each site, and several habitat metrics determined using analyses of aerial photographs. Median time of egg capture was negatively correlated to site discharge. The temporal extent of the sampling period at each site was negatively correlated to both site discharge and habitat-patch dispersion. Our results highlight the role of discharge in driving transport times, but also indicate that higher dispersion of habitat patches relates to increased retention of beads within the river. These results could be used to target restoration activities or prioritize water use to create and maintain habitat complexity within large, fragmented river systems.

LINK between Degeneration and Regeneration of Human Intervertebral Discs

Back pain affects a large portion of the population across all ages and intervertebral disc (IVD) degeneration is its most implicated common cause. Presently, there are no established treatments to prevent, stop, or even retard disc degeneration, and surgery is often the offered option. Previous studies have shown that Link N can act as a growth factor and stimulate the synthesis of proteoglycans and collagens in bovine IVD in vitro and in intact human IVDs ex vivo, as well as increase disc height in a rabbit model of disc degeneration. However, the sequences in Link N involved in modulating cellular activity are not well understood. To determine if disc cells can proteolytically process Link N, human disc cells in monolayer were exposed to native Link N over a 48-hour period and mass spectrometric analysis revealed that a peptide spanning residues 1 to 8 was generated in the presence of AF cells but not NP cells. Link N 1-8 significantly induced proteoglycan production in the presence of IL-1β in both NP and AF cells, confirming that the biological effect is maintained in the first eight amino acids of the peptide and indicating that the effect is sustained in an inflammatory environment. Thus Link N 1-8 could be a promising candidate for biologically induced disc repair, and the identification of such a stable specific peptide may facilitate the design of compounds to promote disc repair and provide alternatives to surgical intervention for early stage disc degeneration. Acknowledgments The authors thank Ms. Areej Khabut for her assistance with mass spectrometry. This work would not have been possible without funding from the Faculty of Medicine McGill University, AO Spine, North American Spine Society and Canadian Institutes of Health Research. We also thank Transplant Quebec for coordinating the retrieval of human lumbar spines through their organ donation program. Lastly, we thank The Crafoord Foundation and the Inga-Britt &amp; Arne Lundberg Foundation for funding the mass spectrometers used in this study. Disclosure of Interest None declared

FIELD SCALE MODELING TO ESTIMATE PHOSPHORUS AND SEDIMENT LOAD REDUCTIONS USING A NEWLY DEVELOPED GRAPHICAL USER INTERFACE FOR SOIL AND WATER ASSESSMENT TOOL

Streams throughout the North Canadian River watershed in northwest Oklahoma, USA have elevated levels of nutrients and sediment. Soil and Water Assessment Tool (SWAT) was used to identify areas that likely contributed disproportionate amounts of Phosphorus (P) and sediment to Lake Overholser, the receiving reservoir at the watershed outlet. These sites were then targeted by the Oklahoma Conservation Commission (OCC) to implement conservation practices, such as conservation tillage and pasture planting as part of a US Environmental Protection Agency Section 319(h) project. Conservation practices were implemented on 238 fields. The objective of this project was to evaluate conservation practice effectiveness on these fields using the Texas Best Management Evaluation Tool (TBET), a simplified Graphic User Interface (GUI) for SWAT developed for field-scale application. TBET was applied on each field to predict the effects of conservation practice implementation on P and sediment loads. These predictions were used to evaluate the implementation cost (per kg of pollutant) associated with these reductions. Overall the implemented practices were predicted to reduce P loads to Lake Overholser by nine percent. The ‘riparian exclusion’ and ‘riparian exclusion with buffer’ practices provided the greatest reduction in P load while ‘conservation tillage’ and ‘converting wheat to bermuda grass’ produced the largest reduction in sediment load. The most cost efficient practices were ‘converting wheat to bermuda grass’ or ‘native range’ and ‘riparian exclusion’. This project demonstrates the importance of conservation practice selection and evaluation prior to implementation in order to optimize cost share funds. In addition, this information may lead to the implementation of more cost effective practices and an improvement in the overall effectiveness of water quality programs.

C. North American and Canadian literatures and cultures

C. North American and Canadian literatures and cultures

Comparison of Aquifer Sustainability Under Groundwater Administrations in Oklahoma and Texas1

Mittelstet, Aaron R., Michael D. Smolen, Garey A. Fox, and Damian C. Adams, 2011. Comparison of Aquifer Sustainability Under Groundwater Administrations in Oklahoma and Texas. Journal of the American Water Resources Association (JAWRA) 1-8. DOI: 10.1111/j.1752-1688.2011.00524.x Abstract: We compared two approaches to administration of groundwater law on a hydrologic model of the North Canadian River, an alluvial aquifer in northwestern Oklahoma. Oklahoma limits pumping rates to retain 50% aquifer saturated thickness after 20 years of groundwater use. The Texas Panhandle Groundwater Conservation District’s (GCD) rules limit pumping to a rate that consumes no more than 50% of saturated thickness in 50 years, with reevaluation and readjustment of permits every 5 years. Using a hydrologic model (MODFLOW), we simulated river-groundwater interaction and aquifer dynamics under increasing levels of “development” (i.e., increasing groundwater withdrawals). Oklahoma’s approach initially would limit groundwater extraction more than the GCD approach, but the GCD approach would be more protective in the long run. Under Oklahoma rules more than half of aquifer storage would be depleted when development reaches 65%. Reevaluation of permits under the Texas Panhandle GCD approach would severely limit pumping as the 50% level is approached. Both Oklahoma and Texas Panhandle GCD approaches would deplete alluvial base flow at approximately 10% development. Results suggest periodic review of permits could protect aquifer storage and river base flow. Modeling total aquifer storage is more sensitive to recharge rate and aquifer hydraulic conductivity than to specific yield, while river leakage is most sensitive to aquifer hydraulic conductivity followed by specific yield.

Luring Lolita: The Age of Consent and the Burden of Responsibility for Online Luring

This article argues that sexual exploitation is the underlying harm that online luring offences should address, but that social anxieties about youth online sexuality have obscured this underlying harm. Through analyzing North American Internet safety materials and Canadian luring case law, the author finds that on the one hand risks of luring are generalized and on the other limited only to victims under the age of consent. The result is that very often older youth are made responsible for their own victimization, while younger ones are assumed to be victimized and hence denied avenues to sexual expression. By neglecting to analyze online interactions for the dynamics of exploitation, we do a disservice to older youths who are exploited while denying sexual autonomy to youth under the age of consent.

Evaluation of a Stream-Aquifer Analysis Test for Deriving Reach-Scale Streambed Conductance

Extracting groundwater from pumping wells located adjacent to streams can reduce streamflow, a result that is known as alluvial well depletion. Numerous analytical solutions have been developed for alluvial well depletion that vary in their mathematical complexity. Predicted drawdown by the analytical solutions can be matched to observed drawdown from a stream-aquifer analysis (SAA) test (i.e., a pumping test adjacent to a stream) to simultaneously estimate aquifer and streambed hydrologic parameters. However, only a few SAA tests have been documented in the literature and compared to field-measured streambed parameters. Therefore, the objective of this research was to perform an SAA test for the purpose of evaluating the ability of analytical solutions, when applied to the SAA test data, to estimate reach-scale streambed conductance. The SAA test was performed at a well site located adjacent to the North Canadian River in central Oklahoma. Observation wells were installed between the stream and the pumping well and were instrumented with automated water level loggers. The pumping well, located approximately 85 m from the North Canadian River, discharged at a constant rate (2180 m3 d-1) for 90 h. Predicted drawdown by an analytical solution was fit to the observed drawdown to inversely estimate the transmissivity (790 to 950 m2 d-1), specific yield (0.19 to 0.28), and streambed conductance (600 to 1500 m d-1), which was compared to values derived from in-stream measurements (i.e., grain-size analyses on streambed sediment samples and in-stream falling-head permeameter tests). Estimated streambed conductance from the in-stream measurements and the SAA test were both on the order of 1000 m d-1. The similarity in estimates supported the use of SAA tests to derive reach-scale streambed conductance. Both the SAA test and in-stream conductivity measurements suggested minimal streambed hydraulic resistance. Therefore, for this and other streams, simpler analytical solutions may be adequate to inversely estimate the aquifer and streambed hydrologic parameters.

Wissenschaft und Abenteuer in der Arktis

its beginning in 1868 German polar expeditions were focused on scientific exploration. History shows that around 1910 only well prepared and equipped expeditions were successful and could gain valuable experiences. The training expedition of the Bavarian officer Wilhelm Filchner who subsequently led the German Antarctic Expedition (1911–1912) was one of these. This is contrasted by the preliminary expedition to Nordaustlandet (Svalbard) of the west Prussian officer Herbert Schröder-Stranz. Other expeditions gave rise to longrangeinvestigations like the permanently occupied German Geophysical Observatory on Svalbard (1911–1914) established for the investigation of the upper air by aerological measurements to prepare a future exploration of the Arctic by airships.&#x0D; There was a long tradition for German scientific expeditions to Greenland, which is represented for instance by Alfred Wegener‘s meteorological programme to investigate the glacial anticyclone. The year 1930 was a fateful year for German polar research, when he died on the ice-cap and geologist Hans Kurt Erich Krueger vanished in the north Canadian archipelago. Both men represented science as well as adventure.&#x0D; International projects initiated or organised from the German side were always successful. Georg von Neumayer, director of the German Navy Observatory (Deutsche Seewarte), played an important role in organising the 1st International Polar Year (1882–1883) after the untimely death of Karl Weyprecht. Only extensive research without recognition of national borders would provide new scientific knowledge in meteorology and earth magnetics for weather forecast and shipping. After World War I economical ideas concerning the introductionof trans-arctic air traffic lead to the foundation of the International Society for the Exploration of the Arctic Regions by Means of Aircraft (Aeroarctic). In the meteorological planning of the first expedition with the airship LZ 127 “Graf Zeppelin” to the Russian Arctic, the results of the German Geophysical Observatory in Svalbard were used. This paper discusses the connections between science and adventure established through the German expeditions.

Auctions as Multifunctional Systems in the Rhine Valley, Germany, in the Nineteenth Century

Introduction In investigating a social phenomenon of recent centuries it is often worthwhile to glance at today's version of the same event. In relation to auctions, taking stock of North American and Canadian public sales in rural areas may provide a starting point for such an examination: In the predominantly rural area of Pennsylvania, the public sale is one of the few regularly attended traditional social events. It is an event of economic and cultural value: economically it provides an opportunity for purchasing cheap, used household and farm items; it also serves a similar function of social interaction, as do the Grange, camp meetings, county fairs and family reunions (Marsh and Aspinall 1971, 133). Attending at auction sales is a favourite pastime for many Prince Edward Islanders, especially for residents of eastern Prince County. Islanders regard their auctioneers as entertainers and expect to have fun at an auction sale (Thurgood 1994, 103). Are auctions, then, social events with both economic and cultural values, and an appealing form of entertainment? Could this kind of perspective enable us to reach a better understanding of nineteenth-century auctions in the Rhine Valley, Germany? Since auctions have been, and still are, a very complex and multifuncfional phenomenon, it is necessary to study them on different levels. In the following discussion some of the results of a research project conducted by Hildegard Mannheims and Peter Oberem under the author's supervision at the University of Munster, Germany, between 1998 and 2001, are presented (Mannheims and Oberem 2003). The aim of the project was to demonstrate the special importance of auctions as multifuncfional systems within the context of social, economic and urban history, as well as the history of mentality. On the basis of the historical background of the Province of the Rhine in the nineteenth century and its special system of justice, the so-called Rhineland Law, the research focus was concentrated on two regions--the city of Bonn with its rural hinterland, and the agricultural region of Lindlar (Oberbergland). The main sources used in the research were the records of moveable property auctions, committed to writing by notaries on the basis of French models, between 1815 (the first year of the Prussian Rhineland Province) and 1900 (the introduction of the new Civil Code). The database was created from the one hundred and three auction records from the urban and country district of Bonn, and the one hundred and thirty-six auction records from the Magistrate's Court in Lindlar. As these notarial data precisely document how second-hand moveable goods changed hands, there is plenty of information concerning the prior ownership of the items offered for sale, the reasons why they were being sold and the auction conditions. Every lot contained the name of the object offered for sale, the name of the person who had made the highest bid (forename, surname, profession and place of residence) and the auction price. The professions of the prior owners recorded in the data represented a broad spectrum of occupations, and included priests, entrepreneurs, officers, academics, pensioners, merchants, craftsmen of the city of Bonn, farmers, factory workers, craftsmen, grocers, and the local upper class consisting of civil servants, inn-keepers and mayors in the region of Lindlar. The research programme was strongly influenced by inventory studies carried out in the late 1970s, in the department of Volkskunde/European Ethnology at the University of Munster (Mohrmann 1990; 1993; 2003). The objects themselves were seen as the pivotal link in the research enterprise, and questions considered to be of central importance for the conduct and analysis of the research data were those such as: What second-hand goods were offered at town and country auctions in Bonn and Lindlar in the nineteenth century? …

Discourse Quotatives in Australian English: Adolescents Performing Voices

This paper examines the discourse quotatives of Australian English (AE) found in sociolinguistic interviews with adolescents. The investigation focuses on a description of the types and linguistic conditioning of the discourse quotatives and a documentation of the discourse meanings and contexts of their realization. Results indicate that the innovation be + like is located in the discourse quotative system of AE but faces opposition from go, say and the null/zero (Mathis & Yule 1994) form. A comparative analysis of AE with North American, Canadian and British English shows that go and null/zero discourse quotatives are prominent in the data, realized with minimal tense variation, i.e. the Historical Present (HP) dominates. Further, the trajectory of be + like in the AE data confounds the typical accessibility pattern for grammatical person. The form has a relatively limited distribution but appears to be grammaticalized for the third person. Analysis of the discourse context highlights the saliency of oppositional experiences, i.e. 'me and them' tales including voices expressing solidarity with the teller's position. The HP successfully captures both meanings--the enduring ongoing voices of 'others' and the chorus of support from their peers. These meanings effectively exclude the innovation be + like. The AE adolescents appear to be embracing the be + like innovation but its implementation in the system is constrained by the discourse role of the voices, expression of solidarity and the continuing 'other', and the propinquity of null/zero forms.

Phylogeography of the plains killifish, Fundulus zebrinus.

Drainage systems of the Great Plains and western Gulf Slope underwent substantial changes through diversions and stream captures during the Pleistocene, either as the result of the glacial advances or through independent geologic processes. The distributions of a variety of fishes that range across west-central North America, such as the plains killifish (Fundulus zebrinus), are thought to be the product of this Pleistocene influence. We examined the geographic pattern of genetic variation in F. zebrinus using three allozyme loci (n = 793), mitochondrial DNA restriction fragment length polymorphisms (RFLPs, n = 352), and sequencing of the mitochondrial cytochrome oxidase I (COI, n = 23) in an attempt to understand the roles of dispersal and vicariance. The phylogeographic patterns were concordant between the allozyme and mitochondrial data with the exception of the population in the North Canadian River. The populations fell into three geographic assemblages, which we designated as northern, central, and southern. A large phylogenetic break (average Roger's D = 0.702; average sequence divergence in RFLPs = 4.6%; average sequence divergence in COI = 5.5%) separated the northern/central and southern assemblages. The northern region was likely colonized sometime during the mid-Pleistocene. Fish in the Brazos and Pecos Rivers probably reached these drainages through stream captures of the Red River. The large phylogenetic break between the northern/central and southern clades supports previous attempts to recognize two species of plains killifish: F. zebrinus and F. kansae.

PHYLOGEOGRAPHY OF THE PLAINS KILLIFISH, FUNDULUS ZEBRINUS

Drainage systems of the Great Plains and western Gulf Slope underwent substantial changes through diversions and stream captures during the Pleistocene, either as the result of the glacial advances or through independent geologic processes. The distributions of a variety of fishes that range across west-central North America, such as the plains killifish (Fundulus zebrinus), are thought to be the product of this Pleistocene influence. We examined the geographic pattern of genetic variation in F. zebrinus using three allozyme loci (n = 793), mitochondrial DNA restriction fragment length polymorphisms (RFLPs, n = 352), and sequencing of the mitochondrial cytochrome oxidase I (COI, n = 23) in an attempt to understand the roles of dispersal and vicariance. The phylogeographic patterns were concordant between the allozyme and mitochondrial data with the exception of the population in the North Canadian River. The populations fell into three geographic assemblages, which we designated as northern, central, and southern. A large phylogenetic break (average Roger's D = 0.702; average sequence divergence in RFLPs = 4.6%; average sequence divergence in COI = 5.5%) separated the northern/central and southern assemblages. The northern region was likely colonized sometime during the mid-Pleistocene. Fish in the Brazos and Pecos Rivers probably reached these drainages through stream captures of the Red River. The large phylogenetic break between the northern/central and southern clades supports previous attempts to recognize two species of plains killifish: F. zebrinus and F. kansae.

Re-embedding, Japanese Investment and the Restructuring Buyer‐Supplier Relations in the Canadian Automotive Components Industry During the 1990s

RUTHERFORD T. D.(2000) Re - embedding, Japanese investment and the restructuring buyer - supplier relations in the Canadian automotive components industry during the 1990s, Reg. Studies 34, 739-751. In this paper, I draw on the developing embeddedness literature in economic geography and consider the impact of Japanese automotive transplants on the Canadian automotive components sector. Following SAKO, 1992, I argue that Japanese firms are seeking to 're - embed' their obligational contractual relations (OCR) supply operations in North America. While this has had a significant impact on North American assemblers and Canadian suppliers, strong elements of the more price - focused and adversarial arm's length contractual relations (ACR) system remain. Although Japanese assemblers share greater non - price information with suppliers and have encouraged greater supplier collaboration, Canadian firms primarily supply low value - added components. Smaller production runs and the sourcing of sophisticated components from Japan and kieretsu operations in the US mean that dense, localized supplier networks are less likely to develop in Canada than in Japan or the US. Attempts to develop greater sectoral and labour management collaboration by Canadian suppliers over product development and training have also been limited. RUTHERFORD T. D. (2000) Enchâssement, investissement direct japonais et restructuration du rapport acheteur- fournisseur au sein de l'industrie des équipementiers canadiens dans les années 1990, Reg. Studies 34, 739-751. Cet article cherche à puiser dans les ouvrages naissants de la géographie économique à propos de la notion d'enchâssement et à examiner l'impact de l'investissement direct japonais dans l'automobile sur les équipementiers canadiens. D'après SAKO, 1992, on affirme que les entreprises japonaises cherchent à 'ré-enchâsser' leurs engagements contractuels (appelés Obligational Contract Relations; OCR) en tant que fournisseurs en Amérique du Nord. Alors que cela a eu un impact non-négligeable sur les usines de montage nordaméricaines et sur les fournisseurs canadiens, il reste d'importants éléments d'un système sans lien de dépendance (appellé Arm's Length Contract; ACR) qui porte plutôt sur le prix et qui s'avère plus antagoniste. Bien que les usines de montage japonaises partagent avec les fournisseurs plus d'information ne portant pas sur les prix et ont encouragé plus de collaboration entre les fournisseurs, les entreprises canadiennes fournissent essentiellement des pièces dont la valeur ajoutée s'annonce faible. Vu les séries plus petites et l'acquisition des pièces plus sophistiquées à partir du Japon et des opérations de kieretsu aux Etats-Unis, il y a peu de chances que d'importants réseaux de fournisseurs, établis sur le plan local, aillent se développer au Canada plutôt qu'au Japon ou aux Etats-Unis. Les mesures prises en faveur d'une collaboration plus étroite dans le domaine du management du secteur et de l'emploi par rapport au développement de produits et à la formation, s'avèrent aussi très limitées. RUTHERFORD T. D. (2000) Wiedereinbettung, japanische Investierungen und die Umstrukturierung von Käufer- Zulieferbeziehungen in der kanadischen Automotivkomponentenindustrie der neunziger Jahre, Reg. Studies 34, 739- 751. Dieser Aufsatz stützt sich die in der Wirtschaftsgeographie in Entwicklung begriffenen Einbettungsliteratur, und betrachtet die Auswirkung japanischer automotiver Verpflanzungen auf den Sektor kanadischer Automotivkomponenten. In Anlehnung an SAKO, 1992, wird die Behauptung aufgestellt, daß japanische Firmen versuchen, ihre durch kontraktlich festgelegte Beziehungen (Obligational Contract Relations (OCR)) eingerichteten Lieferunternehmen in Nordamerika 'wieder einzubetten'. Obschon dies sich beträchtlich auf nordamerikanische Montage- und kanadische Lieferfirmen ausgewirkt hat, blieben starke Elemente des preisbewußten und gegnerischen, auf Abstand bestehenden (Arm's Length Contract (ACR)) Systems bestehen. Obwohl japanische Montagefirmen mehr nichtpreisbezogenen Informationsaustausch mit Lieferanten pflegen, und mehr Zusammenarbeit unter Lieferanten empfehlen, liefern kanadische Firmen in erster Linie Komponenten mit geringem Mehrwert. Kleinere Produktionsserien und der Bezug hochentwickelter Komponenten aus Japan, sowie kieretsu Arbeitsvorgänge in den USA bedeuten, daß dichte, örtlich gebundene Lieferantennetzwerke sich eher in Japan oder den USA als in Kanada entwickeln. Versuche, durch Produktentwicklung mehr Zusammenarbeit kanadischer Lieferfirmen in der Abteilungsleitung und sonalleitung zu erreichen, war auch nur begrenzter Erfolg beschieden.

Equivalent dose distribution analysis of Holocene eolian and fluvial quartz sands from Central Oklahoma

Holocene quartz sands were collected from fluvial terrace deposits and eolian dune deposits adjacent to the North Canadian and Cimarron Rivers and their tributaries in Central Oklahoma. Single aliquot regenerative dose optically stimulated luminescence techniques were employed to generate equivalent dose (ED) distribution histograms for each sample. We hypothesize that the ED distributions are convolutions of the distribution arising from natural sedimentary processes, influenced primarily by the degree of solar resetting experienced by individual grains, and a distribution due to experimental error. An estimation of the experimental error distribution for each sample was made and this was then deconvolved from the experimentally measured ED distribution to reveal the ‘sedimentary process’ ED distribution. Objective methods for determining EDs, uncertainties, and confidence parameters from the deconvolved distributions are presented.