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[Excerpt] Upon reading Benjamin Lefebvre’s introduction to the second volume of his L.M. Montgomery Reader, which appears to catalogue nearly every major piece of scholarly criticism about Montgomery, one is immediately struck by the meticulous and exhaustive nature of the archival research that went into the creation of this three-volume series.

[Extract] In this reader of previously uncollected materials, Benjamin Lefebvre sheds new light on L.M. Montgomery, a figure described by Irene Gammel as 'Canada's most enigmatic literary icon' (p. 5). In this first volume Lefebvre gathers eighty pieces ranging in date from the publication of Anne of Green Gables in 1908 until shortly after Montgomery's death in 1942. These materials include essays and letters written by Montgomery herself for various newspapers and periodicals, as well as a large collection of interviews and author profiles written about her that were published throughout her career. Many of these articles are hard to locate and largely inaccessible to the general public and scholarly community, ensuring that much of the content of this reader will be new even to long-standing Montgomery scholars and enthusiasts. Continuing in this vein, the second volume in this series, titled A Critical Heritage, will focus on reprinting 'milestones (p. 6) in Montgomery scholarship; the third, titled A Legacy in Review, will compile book reviews on Montgomery's work from newspapers, magazines and journals.

The only available tabletop electron storage rings are the machines from the MIRRORCLE series. The electrons are accelerated in a microtron and injected into the storage ring. During its circulation, each electron passes through a tiny target many times, emitting a photon beam. Both the spectrum and the angular distribution of the radiation depend on the material, the thickness and the shape of the target. In this paper measured angular distributions of the radiation from several different targets in the magnetic field of the 20 MeV storage ring MIRRORCLE-20SX are presented. The detector comprises a 3 mm × 3 mm × 8.5 µm plastic scintillator (PS) coupled to a photomultiplier by a bundle of optical fibers. The output of the photomultiplier is digitized by an IF converter. This detector is sensitive mostly to soft X-ray radiation, and its PS is moved by a mechanical system in a plane perpendicular to the radiation axis. The measured angular distributions for Mo and Sn targets contain an annulus which is attributed to transition radiation. The angular distributions for Al, carbon nanotube and diamond-like carbon (DLC) targets show some suppression of the radiation along the magnetic field. This is the first evidence of observation of the angular distribution of synchrotron Cherenkov radiation, which represents Cherenkov radiation in a magnetic field. The power radiated from the DLC target is estimated.

The effect of twist and solvent densification on the internal structure of carbon nanotube yarns was revealed using focused ion beam milling and related to yarn strength through tensile testing. Denser carbon nanotube yarns with smaller diameters were produced either through solvent densification or with increasing twist densities from 5 to ∼15 turns/mm, but led to only minor improvement in yarn tenacity. At twist densities greater than ∼15 turns/mm, a core-sheath structure developed and was correlated with a decline in strength. The implications of bonding between the nanotubes in the twisted yarn are briefly considered. These results have implications for the future development of high strength carbon nanotube yarn.

The efficacy with which a range of nanotubes could reinforce a high density polyethylene (HDPE) matrix was investigated, in relation to nanotube diameter, purity, functionalization, alignment and nanotube bulk density. Composites were prepared by melt blending multiwall carbon nanotubes (MWNTs) with high density polyethylene (HDPE), followed by the injection molding of tensile specimens. At a 5 wt% loading, the most effective nanotubes were those of large diameter, received in an aligned form with low bulk density, producing a 66% increase in elastic modulus and a 69% improvement in yield stress. This was contradictory to theoretical mechanics calculations that predicted an increasing degree of reinforcement for nanotubes of reduced diameter. This difference was explained by the higher degree of dispersion observed in the composites with MWNTs of greater diameter.

The effect of reversing the direction of rotation of workers on the swift of a worsted card was studied in a trial that included processing to top. Experimental conditions studied were worker draft (three levels), doffer draft (two levels), and wool type (two levels). Production rate was held constant throughout at values typical for worsted carding, ~1 gsm production fiber density on the swift and standard topmaking procedures were used after carding. The results showed that the only effect of reversing the direction of rotation identified was increased fiber breakage and noil at the lowest opening roller draft (0.4 %). A tracer fiber study failed to identify any effect of the direction of worker rotation on the fiber structure of the card web. The reason for the increased fiber breakage with reversed direction of rotation at very low draft was thought to be the increased loading in the nip due to the trailing ends of the fibers. The implications of reversing worker rotation for roller carding in general are briefly considered.

A parametric model of fiber transfer to a doffer, based on the geometry of the system and physical models of fiber transfer, was developed to describe the efficiency with which doffers collect fiber from the high-speed carding roller. Doffer speed, normalized to that of the cylinder, was adopted as the variable and parameters, such as wire height, pitch, width, and fiber-layer thickness on the cylinder, were introduced to describe the process of fiber transfer. The equation for doffer efficiency developed by this procedure was tested by fitting it to data on hauteur and noil from a worsted-carding trial employing a range of drafts and production rates. The calculated efficiency of the doffer for these trials was found to lie in the range 0.15—0.25. The effects of changes in the dimensions of the card wire and layer thickness were predicted by changing the values of the parameters.

Noil is waste fiber generated during combing of staple fiber, the level of which is generally a concern due to the associated economic loss. Strategies to reduce noil have not developed because there has not been a reliable, comprehensive, and accurate method of measurement in a combing plant. We describe here a new method for the continuous, automatic monitoring of the total noil without any interference with operator procedures or production. The noil monitoring system was installed on eight combs in a commercial topmaking plant and tested for 24 hours a day for six months. The data obtained from this trial revealed important performance details of the combing operation, such as noil level and noil production, linear density of the prepared and combed slivers, the number of slivers in the feed, production rate of each comb, the feed rate to each comb, machine operating speed, run-time and down-time for each comb, and comb process efficiencies. The data confirmed that this system could be used as a tool for improving management and control of combing.

Two centuries of hunting, agriculture and economic development have caused declining biodiversity and ecological integrity in the prairie ecozone of southern Saskatchewan. The environmental revolution that started in the 1970s brought a renewed vision to protect remaining wildlife and its habitat, and restore keystone mammals. NGOs and government agencies are acting as partners in this vision, and have been increasingly successful in working cooperatively with land-users such as ranchers, farmers and the water and energy industries. New conservation areas and new initiatives to reintroduce extirpated animals and their habitat offer hope to those who wish to see a new balance between prairie inhabitants and wild nature. However, conservation is not an exact science, and 'fashions' and 'agendas' exist, with inevitable debates about priorities. The article assesses the successes and limitations of these conservation initiatives in the Saskatchewan prairies, and draws conclusions relevant to nature conservati...

Carbon nanotubes (CNTs) have a range of useful properties, such as high strength and modulus, high electrical and thermal conductivities, are stable at relatively high and low temperatures, and because of a low density, the specific properties are even better. For these reasons, CNTs are of great technological interest, however, difficulties in assembling the trillions of nanotubes into macro-sized objects without the use of binders has retarded the growth of practical applications. The work presented outlines efforts to develop a solid-state process for nanotube assembly that promises to eliminate the requirement to use binders and capture the inherent properties of nanotubes. These processes include spinning CNT forests into yarns having toughness and high electrical conductivity, and drawing the forests to form webs with gravimetric strengths higher than high tensile steel plate. Both yarns and webs have high electrical conductivities and can be used for emission of light by incandescence.

Individual carbon nanotubes are like minute bits of string, and many trillions of these invisible strings must be assembled to make useful macroscopic articles. We demonstrated such assembly at rates above 7 meters per minute by cooperatively rotating carbon nanotubes in vertically oriented nanotube arrays (forests) and made 5-centimeter-wide, meter-long transparent sheets. These self-supporting nanotube sheets are initially formed as a highly anisotropic electronically conducting aerogel that can be densified into strong sheets that are as thin as 50 nanometers. The measured gravimetric strength of orthogonally oriented sheet arrays exceeds that of sheets of high-strength steel. These nanotube sheets have been used in laboratory demonstrations for the microwave bonding of plastics and for making transparent, highly elastomeric electrodes; planar sources of polarized broad-band radiation; conducting appliqués; and flexible organic light-emitting diodes.

PRESIDENTIAL ADDRESSES TRADITIONALLY TAKE one of several forms.1 Some review the activities and achievements of the Association or Society over the period of office. This approach would not be difficult here, given the outstanding contributions which our great Association continues to make to the field in Canadian Studies. On the other hand, Presidents of Societies involved with Science or Technology may take the opportunity to present the results of their own latest researches within the discipline. Alternatively Presidential addresses might take a more philosophical and reflective view of the development of their particular subject over the President's career in it. There is clearly no single prescription, and indeed Presidents of bacs have often been Presidents of other Associations and Societies in their own specialist disciplines, and have usually adopted different styles when addressing different bodies. The present Address builds on some elements from each of these diverse approaches. The central concern is with Wilderness, which is a tangible natural entity, existing out there in the real world. It can be visited, and evokes in visitors a range of feelings from awe to fear. Yet wilderness is much more than this; it is also a perception, a concept, and an inspiration. Or rather, it forms a complex of perceptions, concepts and inspirations, and leads Warecki (2000) to note: 'Wilderness ideas are a tangle of unresolved contradictions.' The author's long-standing commitment to Canada has been through the discipline of geography, specifically in the sub-disciplines of physical geography (qua environmental studies/sciences) and natural resource studies. It is a journey which has visited the forests of Vancouver Island, the alpine meadows of Kananaskis, the prairie farms of Saskatchewan, the Northern tundras of Rankin Inlet, the Mackenzie Valley and Devon Island, and the farms of southern Ontario and Quebec. However, engagement over the years with annual conferences, colloquia, forums and visiting lectures on Canada, continue to reinforce the conviction that the strength of Canadian Studies lies in its multidisciplinary format. This is the attraction for both faculty and for students. The two academic institutions with which the writer is associated in Yorkshire, namely the University of Leeds and York St John College, both offer multidisciplinary courses on Canada which recruit very well. A major part of their appeal lies in the multidisciplinarity of the courses. Although both are convened by geographers and registered as geography courses, each covers material from history, literature and culture, as one would expect from their subtitle - Environment, People, Culture. Perceptions of Canada among non-Canadians have been polled recently among both faculty and students, including those who have completed the Canadian Studies course in the University of Leeds, and some who have not. The results are revealing of the major 'strengths' or positive values by which Canada is viewed by outsiders, and are shown in Figure 1. The three major images point to multiculturalism and the way in which Canadian society deals with it, to the environment and its beauty and conservation, and to Canada's role in the world. Thus environment and wilderness rank among the 'big issues'. Some readers will be disappointed that their own personal love ranks lower in the list, or not at all; the writer's predilection for Oscar Peterson and Angela Hewitt will be mirrored in many hearts and minds, but not unfortunately in the 'league tables'! What is wilderness? The cultural identity of Canada owes much to 'the wilderness.' It is a central theme in Canadian cinema, conservation, history, literature, livelihoods, music, painting and recreation. Popular images of wilderness abound on television screens, in newspaper supplements, and in travel brochures. Words to express such images might be: 'cold', 'forbidding', 'home of wild animals', 'magnificent sights', 'mysterious', and 'unknown'. …

Carbon nanotubes (CNTs) are of great technical interest because of their high strength (~37 GPa), good electrical conductivity, excellent thermal conductivity (3 000 W m-1K-1), and good thermal stability at both low and high temperatures. A difficulty has been absence of reliable methods of controlling assembly of the large numbers of CNTs required for practical applications. We have developed, in collaboration with our partners at the NanoTech Institute, University of Texas at Dallas, a solid-state process for spinning CNTs into yarns without the use of binders that usually degrade the electrical and thermal conductivities. The singles yarns were twisted together to give coarser (multi-stranded) stronger yarns that were knitted using a miniature 5-needle machine. Mechanical and electrical properties of the yarns and knitted tubes were assessed simultaneously using specially developed test equipment. Some specific applications under investigation include using the CNT yarns as incandescent and x-ray filaments, as electrodes for biomedical applications, and as composites with high toughness. Tests show the biocompatibility of the CNT yarns for selected cell lines is high.