Biodiversity of amoebae and amoebae-resisting bacteria in a drinking water treatment plant

The complex ecology of free-living amoebae (FLA) and their role in spreading pathogenic microorganisms through water systems have recently raised considerable interest. In this study, we investigated the presence of FLA and amoebae-resisting bacteria (ARB) at various stages of a drinking water plant fed with river water. We isolated various amoebal species from the river and from several points within the plant, mostly at early steps of water treatment. Echinamoeba- and Hartmannella-related amoebae were mainly recovered in the drinking water plant whereas Acanthamoeba- and Naegleria-related amoebae were recovered from the river water and the sand filtration units. Some FLA isolates were recovered immediately after the ozonation step, thus suggesting resistance of these microorganisms to this disinfection procedure. A bacterial isolate related to Mycobacterium mucogenicum was recovered from an Echinamoeba-related amoeba isolated from ozone-treated water. Various other ARB were recovered using co-culture with axenic Acanthamoeba castellanii, including mycobacteria, legionella, Chlamydia-like organisms and various proteobacteria. Noteworthy, a new Parachlamydia acanthamoebae strain was recovered from river water and from granular activated carbon (GAC) biofilm. As amoebae mainly multiply in sand and GAC filters, optimization of filter backwash procedures probably offers a possibility to better control these protists and the risk associated with their intracellular hosts

Contracts, Reference Points, and Competition - Behavioral Effects of the Fundamental Transformation

In this paper we study the role of incomplete ex ante contracts for ex post trade. Previous experimental evidence indicates that a contract provides a reference point for entitlements when the terms are negotiated in a competitive market. We show that this finding no longer holds when the terms are determined in a non-competitive way. Our results imply that the presence of a "fundamental transformation" (i.e., the transition from a competitive market to a bilateral relationship) is important for a contract to become a reference point. To the best of our knowledge this behavioral aspect of the fundamental transformation has not been shown before.

Premières conséquences de la guerre : transformation mentale des peuples... / Dr Gustave Le Bon

Collection : Bibliothèque de philosophie scientifique

Les 5 milliards sont là ! ! ! sans emprunt ni augmentation des charges publiques par la seule transformation de l'impôt... 2e édition

Comprend : Préambule

Gadamer's transformation of hermeneutics : from Dilthey to Heidegger

Abstract: The purpose of this paper is to show how Gadamer's hermeneutics synthesizes the insights of both Heidegger and Dilthey in order to introduce a new hermeneutics. Gadamer's hermeneutics is based not only on the priority of ontology, as Heidegger insists, and neither is it only a product of life which can be objectively understood through study and rigorous method, as Dilthey suggests. For Gadamer, hermeneutics is the bringing together of ontology in terms of history. By this synthesis Gadamer not only places himself within the context of a Lebensphilosophie, but also shows that it is within language that Being can be disclosed according to a lived context. Throughout this paper the philosophies ofDilthey and Heidegger are explicated within a historical context as to bring out how, and why, Gadamer sees the need to surpass these philosophies. Through Gadamer's philosophy of play and the game, language, the dialogical model, application, and the fusion of horizons we can see how Gadamer's critique and questioning of these two philosophy leads to his new hermeneutics. Special attention is paid to the role in which these two contrasting philosophies were used to complement each other in the product of Gadamer' s philosophical hermeneutics as it is presented in his major work Truth andMethod. For Gadamer, the task of understanding is never complete. Therefore, his hermeneutics remains a dynamic structure with which we can always question the past and our traditions. This paper seeks to show his philosophical movements within these questions

The essence of a tacit intersection : a heuristic inquiry into nature-based leisure and personal transformation

There are a considerable number of programs and agencies that count on the existence of a unique relationship between nature and human development. In addition, there are significant bodies of literature dedicated to understanding developmentally focused nature-based experiences. This research project was designed to flirther the understanding of this phenomenon. Consequently, the purpose of this research endeavour was to discover the essence ofthe intersection ofpersonal transformation and nature-based leisure, culminating in a rich and detailed account of this otherwise tacit phenomenon. As such, this research built on the assumption of this beneficial intersection of nature and personal transformation and contributes to the understanding ofhow this context is supporting or generating of selfactualization and positive development. Heuristic methods were employed because heuristics is concerned with the quality and essence of an experience, not causal relationships (Moustakas, 1990). Heuristic inquiry begins with the primary researcher and her personal experience and knowledge of the phenomenon. This study also involved four other coresearchers who had also experienced this phenomenon intensely. Co-researchers were found through purposeful and snowball sampling. Rich narrative descriptions of their experiences were gathered through in-depth, semi-structured interviews, and artifact elicitation was employed as a means to get at co-researchers' tacit knowledge. Each coresearcher was interviewed twice (the first interview focused on personal transformation, the second on nature) for approximately four and a half hours in total. Transcripts were read repeatedly to discern patterns that emerged from the study of the narratives and were coded accordingly. Individual narratives were consolidated to create a composite narrative of the experience. Finally, a creative synthesis was developed to represent the essence of this tacit experience. In conclusion the essence of the intersection of nature-based leisure and personal transformation was found to lie in the convergence of the lived experience of authenticity. The physical environment of nature was perceived and experienced to be a space and context of authenticity, leisure experiences were experienced as an engagement of authenticity, and individuals themselves encountered a true or authentic self that emanated from within. The implications of these findings are many, offering suggestions, considerations and implications from reconsidered approaches to environmental education to support for selfdirected human development.

Words on wisdom: perspective transformation in a "learning in retirement institute" /

In this study, 7 men and women with an average age of 77 were interviewed regarding their experience of attending courses at a Learning in Retirement Institute (LRI) in southern Ontario. The purpose was to explore the role of wisdom in the learning of these retirees. Explicit theories of wisdom developed by selected philosophers, psychologists, and religious thinkers were compared to the implicit theories of wisdom that respondents expressed. Further comparisons were drawn between these implicit theories of wisdom and the act of perspective transformation in transformative learning. Some evidence was found that the development of wisdom compares favourably to perspective transformation, especially with regards to the behavioural changes associated with critical self-reflection. Among all the respondents, those 3 LRI stude.its who had also moderated courses indicated that they had experienced the most opportunities for critical self-reflection. These 3 also expressed deep satisfaction in having been able to put their learnings to use as teachers. A recommendation of this study is that opportunities for sharing and acting upon the results of discourse within Learning in Retirement Institutes should be implemented. In the absence of evaluation, opportunities for praxis (such as coop placements) must be developed so that students can measure their success against objective criteria and hence attach meaning to their studies.

Syntrophic relationships between algae and bacteria in a fresh-water stream and in culture /

Interactions between freshwater algae and bacteria were examined in a natural stream habitat and a laboratory model. Field observations provided circumstantial evidence, in statistical correlation for syntrophy between the microbial populations. This relation is probably subject to control by the temperature and pH of the aquatic environment. Several species of a pond community were isolated in axenic culture and tests were performed to determine the nature of mixed species interactions. Isolation procedures and field studies indicated that selected strains of Chlorella and Azotobacter were closely associated in their natural habitat. With the suspected controlling parameters, pH and temperature, held constant, mixed cultures of algae and bacteria were compared to axenic cultures of the same organisms, and a mutual stimulation of growth was observed. A mixed pure culture apparatus was designed in this laboratory to study the algal-bacterial interaction and to test the hypothesis that such an interaction may take place through a diffusable substance or through certain medium-borne conditions, Azotobacter was found to take up a Chlorella-produced exudate, to stimulate protein synthesis, to enhance chlorophyll production and to cause a numerical increase in the interacting Chlorella population. It is not clear whether control is at the environmental, cellular or genetic level in these mixed population interactions. Experimental observations in the model system, taken with field correlations allow one to state that there may be a direct relationship governing the population fluctuations of these two organisms in their natural stream surroundings.

Paradigms and prisons: a narrative of translation and transformation : my hero's journey from "at-risk" youth to teacher/learner in a jail setting /

All life is suffering. Life is the pursuit ofhappiness. These are two foundational Buddhist dictums that, in their simplicity, I have entirely misunderstood regarding their depth, misreading them as contradictory. Indeed, my superficial interpretations led me to Thoreau's life ofquiet desperation and deep depression. We come to know and bring understanding to our lives by storying them. My own Hero's Journey, the path from my egoic selftoward the universal Self, can be understood as the resultant translations and transformations. Inevitably each of us is involved in such a story, though most are unaware of the stages along our own Hero's journey. ' Narrative honours writing as a means of knowing. The contemplative reflection allows insight into our imprisoning paradigms, beliefs, behaviours, and blind spots. My research revisits and explores nodal experiences along my Hero's Journey through 4 categories: self, society, soil, and Self. While the value of this process of narrative inquiry lay in its ability to come to know and understand one's self, perhaps its greater value is of a more universal nature. My inquiry, while adding to the body of academic educational narrative literature, may also illuminate a path to educators, students, and all interested, encouraging a response to the call of their own Hero's journey. I am a teacher/learner in a jail setting, working with youth between the ages of 12 and 18 who have committed crimes such as armed robbery, assault, rape, and murder. As this thesis follows my continual development from egoic self/teacher/learner to universal Self/Teacher/Learner, it also enables me to both consciously and unconsciously open the ways in which I expand my care, compassion, and love to work with at-risk youth.

An exploration of transformation theory and the western tradition: a critical evaluation of a graduate studies class

This qualitative study is an exploration of transformation theory, the Western tradition, and a critical evaluation of a graduate studies class at a university. It is an exploration of assumptions that are embedded in experience, that influence the experience and provide meaning about the experience. An attempt has been made to identify assumptions that are embedded in Western experience and connect them with assumptions that shape the graduate class experience. The focus is on assumptions that facilitate and impede large group discussions. Jungian psychology of personality type and archetype and developmental psychology is used to analyze the group experience. The pragmatic problem solving model, developed by Knoop, is used to guide thinking about the Western tradition. It is used to guide the analysis, synthesis and writing of the experience of the graduate studies class members. A search through Western history, philosophy. and science revealed assumptions about the nature of truth, reality, and the self. Assumptions embedded in Western thinking about the subject-object relationship, unity and diversity are made explicit. An attempt is made to identify Western tradition assumptions underlying transformation theory. The critical evaluation of the graduate studies class experience focuses upon issues associated with group process, self-directed learning, the educator-learner transaction and the definition of adult education. The advantages of making implicit assumptions explicit is explored.

Ecological interactions between zooplankton and photosynthetic bacteria in Crawford Lake, Ontario

The present study was carried out to test the hypothesis that photosynthetic bacteria contribute a large portion of the food of filter feeding zooplankton populations in Crawford Lake, Ontario. The temporal and spatial variations of both groups of organisms are strongly dependent on one another. 14 By using C-Iabelled photosynthetic bacteria. the ingestion and clearance rates of Daphnia pulex, ~. rosea, and Keratella spp were estimated during summer and fall of 1982. These quantitative estimations of zooplankton ingestion and clearence rates on photosynthetic bacteria comprised an original addition to the literature. Photosynthetic bacteria comprised a substantial portion of the diet of all four dominant zooplankton species. The evidence for this is based on the ingestion and clearance rates of the dominant zooplankton species. Ingestion rates of D. pulex and D. rosea ranged 5 5 -1 -1 - -- 5 - -- 5 from 8.3X10 -1 to 14.6XlO -1 cells.ind. hr and 8.1X10 to 13.9X10 cells.ind. hr • Their clearance rates ranged from 0.400 to 1.000 -1 -1 -1 -1 ml.ind. hr. and 0.380 to 0.930 ml.ind. hr • The ingestion and clearance -1 -1 -1 -1 rates of Keratella spp were 600 cell.ind. hr and 0.40 ul.ind. hr respectively. Clearance rates were inversely proportional to the concentration of food cells and directly proportional to the body size of the animals. It is believed that despite the very short reg~neration times of photosynthetic bacteria (3-8 hours) their population densities were controlled in part by the feeding rates of the dominant zooplankton in Crawford Lake. By considering the regeneration times of photosynthetic bacteria and the population clearance rates of zooplankton, it was estimated that between 16 to 52% and 11 to 35% of the PHotosynthetic bacteria were' consumed· by Daphnia· pulex. and Q.. rosea per day. The temporal and spatial distribution of Daphnia pulex, !.. rosea, Keratella quadrata, K. coChlearis and photosynthetic bacteria in Crawford Lake were also investigated during the period of October, 1981 to December, 1982. The photosynthetic bacteria in the lake, constituted a major food source for only those zooplankton Which tolerate anaerobic conditions. Changes in temperature and food appeared to correlate with the seasonal changes in zooplankton density. All four dominant species of zooplankton were abundant at the lake's surface (O-4m) during winter and spring and moved downwards with the thermocline as summer stratification proceeded. Photosynthetic bacteria formed a 2 m thick layer at the chemocline. The position of this photosynthetic bacterial J-ayer changed seasonally. In the summer, the bacterial plate moved upwards and following fall mixing it moved downwards. A vertical shift of O.8m (14.5 to 15.3m) was recorded during the period of June to December. The upper limit of the photosynthetic bacteria in the water column was controlled by dissolved oxygen, and sulfide concentrations While their lower limit was controlled by light intensity. A maximum bacterio- 1 chlorophyll concentration of 81 mg Bchl.l was recorded on August 9, 1981. The seasonal distribution of photosynthetic bacteria was controlledinpart' by ·theg.-"z1ai'_.Q;~.zoopl. ank:tCm;-.Qther -ciactors associated with zooplankton grazing were oxygen and sulfide concentrations.

Factors influencing the seasonal changes in primary productivity of the photosynthetic bacteria of Crawford Lake, Ontario

A naturally occurring population of photosynthetic bacteria, located in the meromictic Crawford Lake, was examined during two field seasons (1979-1981). Primary production, biomass, light intensity, lake transparency, pH and bicarbonate concentration were all monitored during this period at selected time intervals. Analysis of the data indicated that (l4C) bacterial photosynthesis was potentially limited by the ambient bicarbonate concentration. Once a threshold value (of 270 mg/l) was reached a dramatic (2 to 10 fold) increase in the primary productivity of the bacteria was observed. Light intensity appeared to have very little effect on the primary productivity of the bacteria, even at times when analyses by Parkin and Brock (1980a) suggested that light intensity could be limiting (i.e., 3.0-5.0 ft. candles). Shifts in the absorption maxima at 430 nrn of the .bacteriochlorophyll spectrum suggested that changes in the species or strain composition of the photosynthetic bacteria had occurred during the summer months. It was speculated that these changes might reflect seasonal variation in the wavelength of light reaching the bacteria. Chemocline erosion did not have the same effect on the population size (biomass) of the photosynthetic bacteria in Crawford Lake (this thesis) as it did in Pink Lake (Dickman, 1979). In Crawford Lake the depth of the chemocline was lowered with no apparent loss in biomass (according to bacteriochlorophyll data). A reverse current was. proposed to explain the observation. The photosynthetic bacteria contributed a significant proportion (10-60%) of the lake1s primary productivitya Direct evidence was obtained with (14C) labelling of the photosynthetic bacteria, indica.ting that the zooplankton were grazing the photosynthetic bacteria. This indicated that some of the photosynthetic bacterial productivity was assimilated into the food chain of the lake. Therefore, it was concluded that the photosynthetic bacteria made a significant contribution to the total productivity of Crawford Lake.