Showing papers by "University of Alberta published in 1996"

Understanding Radical Organizational Change: Bringing Together the Old and the New Institutionalism

Abstract: The complexity of political, regulatory, and technological changes confronting most organizations has made radical organizational change and adaptation a central research issue. This article sets out a framework for understanding organizational changes from the perspective of neo-institutional theory. The principal theoretical issue addressed in the article is the interaction of organizational context and organizational action. The article examines the processes by which individual organizations retain, adopt, and discard templates for organizing, given the institutionalized nature of organizational fields.

Solvent microextraction into a single drop.

Abstract: An analytical technique is described which combines solvent extraction with gas chromatographic (GC) analysis in a simple and inexpensive apparatus involving very little solvent consumption. A small drop (8 μL) of a water-immiscible organic solvent, containing an internal standard, is located at the end of a Teflon rod which is immersed in a stirred aqueous sample solution. After the solution has been stirred for a prescribed period of time, the probe is withdrawn from the aqueous solution, and the organic phase is sampled with a microsyringe and injected into the GC for quantification. The observed rate of solvent extraction is in good agreement with a convective−diffusive kinetic model. Analytically, the relative standard deviation of the method is 1.7% for a 5.00-min extraction of the analyte 4-methylacetophenone into n-octane.

Cardiac Troponin T Levels for Risk Stratification in Acute Myocardial Ischemia

Abstract: Background The prognosis of patients hospitalized with acute myocardial ischemia is quite variable. We examined the value of serum levels of cardiac troponin T, serum creatine kinase MB (CK-MB) levels, and electrocardiographic abnormalities for risk stratification in patients with acute myocardial ischemia. Methods We studied 855 patients within 12 hours of the onset of symptoms. Cardiac troponin T levels, CK-MB levels, and electrocardiograms were analyzed in a blinded fashion at the core laboratory. We used logistic regression to assess the usefulness of base-line levels of cardiac troponin T and CK-MB and the electrocardiographic category assigned at admission — ST-segment elevation, ST-segment depression, T-wave inversion, or the presence of confounding factors that impair the detection of ischemia (bundle-branch block and paced rhythms) — in predicting outcome. Results On admission, 289 of 801 patients with base-line serum samples had elevated troponin T levels (>0.1 ng per milliliter). Mortality with...

A blinded, randomized clinical trial of mycophenolate mofetil for the prevention of acute rejection in cadaveric renal transplantation

Abstract: Mycopehenolate mofetil (MMF) is a powerful immunosuppressant that inhibits the proliferation of T and B lymphocytes by blocking the enzyme inosine monophosphate dehydrogenase. MMF has been shown to prevent acute graft rejection in animal experiments and may have an important role in clinical renal transplantation. We conducted a prospective, double-blind, multi-center trial to compare the efficacy and safety of MMF and azathioprine within standard immunosuppressive regimen for patients receiving a first or second cadaveric renal graft. A total of 503 patients were randomized to groups receiving MMF 3 g (n=164), MMF 2 g (n=173), or azathioprine (AZA) 100-150 mg (n=166) daily. All were treated simultaneously with equivalent doses of cyclosporine and oral corticosteroids and followed for 12 months. The primary endpoint was treatment failure, defined as the occurrence of biopsy-proven graft rejection, graft loss, patient death, or discontinuation of the study drug during the first 6 months after transplantation. Treatment failure occurred in 50.% of patients in the AZA group by 6 months after transplantation, compared with 34.8% in the MMF 3g group (P=0.0045) and 38.2 % in the MMF 2g group (P=0.0287). Biopsy-proven rejection occurred in 15.9% of patients in the MMF 3 g group and 19.7% in the MMF2 g group, compared with 35.5% in the AZA group. Rejection of histologic severity grade II or more developed in 6.1 %, 10.4% and 19.9% of patients in the MMF 3 g, MMF 2 g, and AZA groups, respectively. Patients receiving MMF required less frequent and less intensive treatment for acute rejection: 24.4% of patients on MMF 3 g and 31.0% on MMF 2 g were tested for acute rejection, compared with 47.5% on AZA. Only 4.9% on MMF 3 g and 8.8% on MMF 2 g required antilymphocyte antibodies for treatment of severe or steroid-resistant rejection, compared with 15.4% of the patients on AZA. At 1 year after transplantation, graft survival in the MMF groups was marginally superior to that in the AZA group, although this difference was not statistically significant. Gastrointestinal toxicity and tissue-invasive cytomegalovirus infection were more common in the MMF 3 g group. Noncutaneous malignancies occurred in six patients on MMF 3 g, three patients on MMF 2 g, and four patients on AZA. Lymphoproliferative disorders occurred in two patients per MMF group, compared with one patient receiving AZA. MMF appears to be an important advance in prophylaxis following renal transplantation. It is associated with a significantly lower rate of treatment failure compared with AZA during the first 6 months after renal transplantation and produces a clinically important reduction in the incidence, severity, and treatment of acute graft rejection. These differences persist throughout the first year of follow-up. Clinical benefit was greatest with a dose of MMF 3 g/day, but gastrointestinal effects, invasive cytomegalovirus infection, and malignancies were slightly more common at that dose. The appropriate dose may lie between 2 g and 3 g per day and may require individualization depending on clinical course or other factors.

Teachers' Professional Knowledge Landscapes: Teacher Stories––Stories of Teachers––School Stories––Stories of Schools

Abstract: G ary Fenstermacher, in The Knower and the Known: The Nature of Knowledge in Research on Teaching (1994), reviewed conceptions of knowledge in the literature of research on teaching. His philosophical interest was an epistemological one, an interest in how "notions of knowledge are used and analyzed in a number of research programs that study teachers and their teaching" (p. 3). Fenstermacher structured his review around four questions that he assumed facilitated his epistemological scrutiny: • What is known about effective teaching? • What do teachers know? • What knowledge is essential for teaching? • Who produces knowledge about teaching? The review is informative on the four questions and raises important epistemological issues. We have no quarrel with the way various bodies of work were classified by his use of the questions. We wish to point out that the success of the use of the questions in facilitating his inquiry rests on the acceptability of the questions in the literature of research on teaching. One way or another, these are the questions that govern this literature. It is those four questions that are in question for us in this paper. Though not stated as such, the review, and the work surveyed, implies that valid, reliable, knowledge on the four questions will make possible better educated teachers. This, of course, was not Fenstermacher's concern. However, it might seem that one could hardly deny this implication. Having reliable answers to these questions would surely do that. What alternative social justifications, after all, might be offered in defense of such research? But we think that answers to these questions are only partially capable of creating understandings that might justify the implication in its full-blown sense. We think the narrative context for the ongoing development and expression of teacher knowledge in schools is also of importance. In response to Fenstermacher's review, we would, therefore, like to raise a fifth question that might be worded, "How is teacher knowledge shaped by the professional knowledge context in which teachers work?" We want to make the case that it is not only an understanding of teacher knowledge and the education of teachers that will make a difference but attention to the professional knowledge context in which teachers live and work. We believe that the professional knowledge context shapes the answers that may be given to Fenstermacher's four questions. The professional knowledge context shapes effective teaching, what teachers know, what knowledge is seen as essential for teaching, and who is warranted to produce knowledge about teaching. To demonstrate this, we draw on an earlier argument for understanding the context for teacher knowledge in terms of the idea of a professional knowledge landscape (Clandinin & Connelly, 1995). Following a brief description of the idea of a professional knowledge landscape, we recount three sets of stories and interpret each in terms of that landscape.

Biopreservation by lactic acid bacteria.

Abstract: Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Lactic acid bacteria have a major potential for use in biopreservation because they are safe to consume and during storage they naturally dominate the microflora of many foods. In milk, brined vegetables, many cereal products and meats with added carbohydrate, the growth of lactic acid bacteria produces a new food product. In raw meats and fish that are chill stored under vacuum or in an environment with elevated carbon dioxide concentration, the lactic acid bacteria become the dominant population and preserve the meat with a "hidden' fermentation. The same applies to processed meats provided that the lactic acid bacteria survive the heat treatment or they are inoculated onto the product after heat treatment. This paper reviews the current status and potential for controlled biopreservation of foods.

A full genome search in multiple sclerosis

Abstract: The aetiology of multiple sclerosis (MS) is uncertain. There is strong circumstantial evidence to indicate it is an autoimmune complex trait. Risks for first degree relatives are increased some 20 fold over the general population. Twin studies have shown monozygotic concordance rates of 25-30% compared to 4% for dizygotic twins and siblings. Studies of adoptees and half sibs show that familial risk is determined by genes, but environmental factors strongly influence observed geographic differences. Studies of candidate genes have been largely unrewarding. We report a genome search using 257 microsatellite markers with average spacing of 15.2 cM in 100 sibling pairs (Table 1, data set 1 - DS1). A locus of lambda>3 was excluded from 88% of the genome. Five loci with maximum lod scores (MLS) of >1 were identified on chromosomes 2, 3, 5, 11 and X. Two additional data sets containing 44 (Table 1, DS2) and 78 sib pairs (Table 1, DS3) respectively, were used to further evaluate the HLA region on 6p21 and a locus on chromosome 5 with an MLS of 4.24. Markers within 6p21 gave MLS of 0.65 (non-significant, NS). However, D6S461, just outside the HLA region, showed significant evidence for linkage disequilibrium by the transmission disequilibrium test (TDT), in all three data sets (for DS1 chi2 = 10.8, adjusted P < 0.01)(DS2 and DS3 chi2 = 10.9, P < 0.0005), suggesting a modest susceptibility locus in this region. On chromosome 5p results from all three data sets (222 sib pairs) yielded a multipoint MLS of 1.6. The results support genetic epidemiological evidence that several genes interact epistatically to determine heritable susceptibility.

Infrared Intensities of Liquids XX: The Intensity of the OH Stretching Band of Liquid Water Revisited, and the Best Current Values of the Optical Constants of H 2 O(l) at 25°C between 15,000 and 1 cm -1

Abstract: The previously reported nonreproducibility of the intensity of the OH stretching band of liquid water has been explored. It was found that it can be eliminated in measurements with the Circle® multiple ATR cell by ensuring that the ATR rod is coaxial with the glass liquid holder. It was also found that normal laboratory temperature variations of a few degrees change the intensity by ≤~1% of the peak height. A new imaginary refractive index spectrum of water has been determined between 4000 and 700 cm-1 as the average of spectra calculated from ATR spectra recorded by four workers in our laboratory over the past seven years. It was obtained under experimental and computational conditions superior to those used previously, but is only marginally different from the spectra reported in 1989. In particular, the integrated intensities of the fundamentals are not changed significantly from those reported in 1989. The available imaginary refractive index, k, values between 15,000 and 1 cm-1 have been compared. The values that are judged to be the most reliable have been combined into a recommended k spectrum of H2O(l) at 25°C between 15,000 and 1 cm-1, from which the real refractive index spectrum has been calculated by Kramers-Kronig transformation. The recommended values of the real and imaginary refractive indices and molar absorption coefficients of liquid water at 25 ± 1 °C are presented in graphs and tables. The real and imaginary dielectric constants and the real and imaginary molar polarizabilities in this wavenumber range can be calculated from the tables. Conservatively estimated probable errors of the recommended k values are given. The precision with which the values can be measured in one laboratory and the relative errors between regions are, of course, far smaller than these probable errors. The recommended k values should be of considerable value as interim standard intensities of liquid water, which will facilitate the transfer of intensities between laboratories.

Sedimentation and Transformation in Organizational Change: The Case of Canadian Law Firms:

Abstract: This paper identifies two archetypes in large Canadian law firms to show how ideas of professionalism and partnership are changing, due in part to shifts in discourses in the wider institutional context. These changes in discourse themselves alter the interpretation of organizational structures and systems. This theme is explored through the concept of tracks and sedimentation. We explore the emergence of an organizational archetype that appears not to be secure, and which results in sedimented structures with competitive commit ments. The geological metaphor of sedimentation allows us to consider a dia lectical rather than a linear view of change. Case studies of two law firms show how one archetype is layered on the other, rather than representing a distinct transformation where one archetype sweeps away the residues of the other.

Consequences of climate warming and lake acidification for UV-B penetration in North American boreal lakes

Abstract: CLIMATE warming, acid deposition and increasing exposure to ultraviolet radiation are all regarded as widespread problems in boreal ecosystems. Here we report observations from twenty years of whole-lake acidification experiments, which show that these three problems are intimately linked. In our study area in northwestern Ontario, both climate warming and lake acidification led to declines in the dissolved organic carbon content of lake waters, allowing increased penetration of solar radiation. We suggest that some of the changes in aquatic ecosystems that have been attributed to lake acidification may in fact have involved increased exposure to ultraviolet light. Moreover, it seems that— particularly in clear, shallow lakes and streams—climate warming and/or acidification can be more effective than stratospheric ozone depletion in increasing the exposure of aquatic organisms to biologically effective UV-B radiation.

The effects of climatic warming on the properties of boreal lakes and streams at the Experimental Lakes Area, northwestern Ontario

Abstract: A period of prolonged warmer, drier-than-normal weather in northwestern Ontario during the 1970s and 1980s resulted in severe forest fires that caused dramatic changes to lake and stream catchments. The changed interactions of weather with catchments and hydrological processes caused unexpected changes in physical, chemical, and biological processes in lakes and streams. Permanent first-order streams became ephemeral. Flows at spring melt were lower, and chemical exports from catchments were reduced. Although catchments burned by forest fire had slightly higher flows and chemical exports than unburned basins in the years following fires, chemical exports generally declined due to lower streamflow. Decreased exports of silica indicated lower rates of weathering. Base cation exports also decreased, as did the ratio of base cations to strong acid anions in streams. Changes in lakes included warmer temperatures, clearer waters, deeper thermoclines and euphotic zones, higher alkalinities, and higher concentrations of base cations and nitrogen, but lower concentrations of dissolved organic C, silica, and P. The increase in alkalinity was caused by increases in the ratio of base cations to strong acid anions, resulting from the interaction of increased water retention, microbial sulfate reduction, and exchanges of cations between water and sediments. Declines in chlorophyll and increases in phytoplankton biomass were observed, but there was no detectable effect on areal phytoplankton production. Summer subthermocline habitats for cold stenotherms were reduced slightly in extent as the results of thermocline deepening and lower hypolimnetic oxygen. There is considerable potential for interaction between climatic change and other human perturbations affecting boreal lakes, including acidification, increased incident UV radiation, eutrophication, and overharvesting.

Control of C. elegans Larval Development by Neuronal Expression of a TGF-β Homolog

Abstract: The Caenorhabditis elegans dauer larva is specialized for dispersal without growth and is formed under conditions of overcrowding and limited food. The daf-7 gene, required for transducing environmental cues that support continuous development with plentiful food, encodes a transforming growth factor-β (TGF-β) superfamily member. A daf-7 reporter construct is expressed in the ASI chemosensory neurons. Dauer-inducing pheromone inhibits daf-7 expression and promotes dauer formation, whereas food reactivates daf-7 expression and promotes recovery from the dauer state. When the food/pheromone ratio is high, the level of daf-7 mRNA peaks during the L1 larval stage, when commitment to non-dauer development is made.

Values and Organizational Structure

Abstract: Recent developments in organizational theory emphasize the need to examine the relationship between organizational values and structure. Values underpin organizational structure and give it meaning. Drawing on concepts of culture, institutional theory, and archetypes, this paper tests hypotheses on the value/structure relationship. The sample used for the study was a set of Canadian amateur sport organizations undergoing institutional change. This test shows that there is a fit between elite values and the nature of the institutionally prescribed organizational archetype.

Meta-Synthesis of Qualitative Findings

Abstract: A framework for synthesizing qualitative findings is described, and issues surrounding employment of this technique are discussed. Further debate on these issues is encouraged to develop and refine this framework. The practical importance of interpretive meta-synthesis is highlighted in relation to theory development.

Distributed and parallel database systems

Abstract: The maturation of database management system (DBMS) technology has coincided with significant developments in distributed computing and parallel processing technologies. The end result is the development of distributed database management systems and parallel database management systems that are now the dominant data management tools for highly data-intensive applications. With the emergence of cloud computing, distributed and parallel database systems have started to converge. In this chapter, we present an overview of the distributed DBMS and parallel DBMS technologies, highlight the unique characteristics of each, and indicate the similarities between them. We also discuss the new challenges and emerging solutions.

Enhancing Communication between Marketing and Engineering: The Moderating Role of Relative Functional Identification

Abstract: Using research in social psychology, the authors illustrate how two key routes to improve communication between marketing and engineering are dependent on the strength of managers' psychological connection to their functional area compared to the firm as a whole (i. e., relative functional identification). In particular, they argue that relative functional identification moderates the relationship between strategies traditionally used to affect interfunctional relationships (information-sharing norms and integrated goals) and the frequency, bidirectionality, and coerciveness of interfunctional communication behaviors. In turn, these communication behaviors are linked to information use and perceived relationship effectiveness. The authors empirically test predictions of the framework in two studies. Study 1 results suggest that (1) the efficacy of the traditional strategies depends on marketing managers' relative functional identification and (2) the traditional strategies can have negative and unintended effects on communication behaviors. In Study 2, the authors replicate and extend Study 1 by illustrating that bidirectional communication is as important as frequency in increasing both information use by engineering personnel and the perceived effectiveness of interfunctional relationships. The authors conclude with implications for theory building and managerial practice.

T helper 1 response against Leishmania major in pregnant C57BL/6 mice increases implantation failure and fetal resorptions. Correlation with increased IFN-gamma and TNF and reduced IL-10 production by placental cells.

Abstract: Maternal immune responses can influence fetal survival and several cytokines have harmful or protective effects on pregnancy. The Th1 cytokines IFN-gamma and IL-2 can cause fetal loss, whereas the Th2 cytokine IL-10 is protective. However, infections such as leishmaniasis show the opposite pattern: resistance is associated with the preferential mounting of a Th1 response, whereas a Th2 response exacerbates the disease. We therefore asked whether the curative Th1 response against Leishmania major in genetically resistant C57BL/6 mice, would compromise concurrent pregnancy. The number of resorptions as assessed by uterine scars was significantly increased in infected C57BL/6 mice and this was associated with a decreased production by placental cells of the Th2 cytokines IL-4 and IL-10 and increased production of IFN-gamma and TNF. Interestingly, the frequency of pregnancy failure before implantation in C57BL/6 mice was also substantially increased. In contrast to C57BL/6 mice, early infection did not reduce implantations in BALB/c mice that mount a Th2 anti-L. major response and succumb to infection. For both resorptions and implantations, there appeared to be a short period early in infection that was detrimental to pregnancy, followed by a period with lesser effects, and a later period that again induced higher resorptions or pre-implantation losses. These results suggest that a beneficial anti-parasite Th1 response can adversely affect pregnancy outcome. Furthermore, Th1 cytokines may be deleterious for not only placental maintenance but also preimplantation events.

Large scale isolation, growth, and function of porcine neonatal islet cells.

Abstract: Based upon existing methods of isolating fetal porcine islet tissue, a simple, reliable procedure was developed for the preparation of porcine neonatal islet cell aggregates with a reproducible and defined cellular composition. After 9 d of in vitro culture, tissue from one neonatal pig pancreas yielded approximately 50,000 islet cell aggregates, consisting of primarily epithelial cells (57%) and pancreatic endocrine cells (35%). During the culture period, the total beta cell mass decreased initially, but subsequently increased 1.5-fold between days 3 and 9. Transplantation of grafts consisting of 3 x 10(5) beta cells (1,000 aggregated) under the kidney capsule of alloxan-diabetic nude mice corrected hyperglycemia in 75% (10/13) of the animals, whereas, 100% (20/20) of recipients implanted with 6 x 10(5) beta cells (2,000 aggregates) achieved euglycemia within 8 wk posttransplantation. Nephrectomy of the graft bearing kidney at 14 wk posttransplantation resulted in hyperglycemia in all recipients, and examination of the grafts revealed the presence of numerous well-granulated insulin- and glucagon-containing cells. The cellular insulin content of these grafts was 20 to 30-fold higher than at the time of transplantation. These results indicate that the neonatal porcine pancrease can be used as a source of large numbers of viable islet cells, which have the potential for growth both in vitro and in vivo, and exhibit the metabolic capacity to correct diabetes in nude mice.

Review of Lagrangian Stochastic Models for Trajectories in the Turbulent Atmosphere

Abstract: We review the theoretical basis for, and the advantages of, random flight models for the trajectories of tracer particles in turbulence. We then survey their application to calculate dispersion in the principal types of atmospheric turbulence (stratified, vertically-inhomogeneous, Gaussian or non-Gaussian turbulence in the surface layer and above), and show that they are especially suitable for some problems (e.g., quantifying ground emissions).

Thermo field dynamics

Abstract: A quantum field theory at finite temperature is presented. The temperature dependent vacuum is defined such that the vacuum expectation value agrees with the statistical average. The vacuum states with different temperature are connected by a Bogoliubov transformation. Our formalism allows the use of the Feynman diagrams for the causal Green’s function and the Bethe-Salpeter technique for bound states at finite temperature, The entropy operator is introduced.

Prox-regular functions in variational analysis

Abstract: The class of prox-regular functions covers all lsc, proper, convex functions, lower-C2 functions and strongly amenable functions, hence a large core of functions of interest in variational analysis and optimization The subgradient mappings associated with prox-regular functions have unusually rich properties, which are brought to light here through the study of the associated Moreau envelope functions and proximal mappings Connections are made between second-order epi-derivatives of the functions and proto-derivatives of their subdifferentials Conditions are identified under which the Moreau envelope functions are convex or strongly convex, even if the given functions are not