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.

Forsaking all others: towards a new model of nationalism utilizing the case study of former Yugoslavia

Many people would like to believe that nationalism is a thing of the past, a dinosaur belonging to some bygone, uncivilized era. Such a belief is not borne out by recent history, however. Nationalism occupies the political forum with as much force as ever. Yet, in many ways, it remains a mystery to us. The purpose of this study is to explore individual motivations involved in the rise of nationalism, in addition to the role of structural factors. The linkage employed in this exploration is the psychosocial phenomenon of self-identity, including emotions and self-esteem. We demonstrate how individual, socially-constructed self-identity accounts for why some people embrace nationalism while others eschew it. The methodology employed was theoretical and historical analyses of secondary sources and indepth interviews with subjects who had some connection with former Yugoslavia, the country utilized to test the new model. Our analyses yielded the result that current conceptualizations of nationalism from an exclusively macro or micro perspective are unsatisfactory; we require a more comprehensive approach wherein the two perspectives are integrated. Such an integration necessitates a bridge: hence, our new model, which rests on the psychosocial premise, offers a more useful conceptual tool for the understanding of nationalism. We conclude that nationalism is first and foremost a matter relating to individual social self-identity which takes place within a particular context where oppositional forces emerge from structural factors and our membership in a particular group becomes paramount.

Letting go : a self-study utilizing critical literacy as method in improving my practice /

This is a Self-study about my role as a teacher, driven by the question: "How do I improve my practice?" (Whitehead, 1989)? In this study, I explored the discomfort that I had with the way that I had been teaching. Specifically, I worked to uncover the reasons behind my obsessive (mis)management of my students. I wrote of how I came to give my Self permission for this critique: how I came to know that all knowledge is a construction, and that my practice, too, is a construction. I grounded this journey within my experiences. I constructed these experiences in narrative fomi in order to reach a greater understanding of how I came to be the teacher I initially was. I explored metaphors that impacted my practice, re-constructed them, and saw more clearly the assumptions and influences that have guided my teaching. I centred my inquiry into my teaching within an Action Reflection methodology, bon-owing Jack Whitehead's (1989) term to describe my version of Action Research. I relied upon the embedded cyclical pattern of Action Reflection to understand my teaching Self: beginning from a critical moment, reflecting upon it, and then taking appropriate action, and continuing in this way, working to improve my practice. To understand these critical moments, I developed a personal definition of critical literacy. I then tumed this definition inward. In treating my practice as a textual production, I applied critical literacy as a framework in coming to know and understand the construction that is my teaching. I grounded my thesis journey within my Self, positioning my study within my experiences of being a grade 1 teacher struggling to teach critical literacy. I then repositioned my journey to that of a grade 1 teacher struggling to use critical literacy to improve my practice. This journey, then, is about the transition from critical literacyit as-subject to critical literacy-as-instmctional-method in improving my practice. I joumeyed inwards, using a critical moment to build new understandings, leading me to the next critical moment, and continued in this cyclical way. I worked in this meandering yet deliberate way to reach a new place in my teaching: one that is more inclusive of all the voices in my room. I concluded my journey with a beginning: a beginning of re-visioning my practice. In telling the stories of my journey, of my teaching, of my experiences, I changed into the teacher that I am more comfortable with. I've come to the frightening conclusion that I am the decisive element in the classroom. It's my personal approach that creates the climate. It's my daily mood that makes the weather As a teacher, I possess a tremendous power to make a person's life miserable or joyous. I can be a tool of torture or an instrument of inspiration. I can humiliate or humour, hurt or heal. In all situations, it is my response that decides whether a crisis will be escalated or de-escalated and a person humanized or de-humanized. (Ginott, as cited in Buscaglia, 2002, p. 22)

Some ecological factors affecting the input and population level of total and faecal coliforms and salmonella in Twelve Mile Creek, Lake Ontario and sewage waters near St. Catharines, Ontario

Some Ecological Factors Affecting the Input and Population Levels of Total and Faecal Coliforms and Salmonella in Twelve Mile Creek, Lake Ontario and Sewage Waters Near St. Catharines, Ontario. Supervisor: Dr. M. Helder. The present study was undertaken to investigate the role of some ecological factors on sewage-Dorne bacteria in waters near St. Catharines, Ontario. Total and faecal coliform levels and the presence of Salmonella were monitored for a period of a year along with determination of temperature, pH, dissolved oxygen, total dissolved solids, nitrate N, total phosphate P and ammonium N. Bacteriological tests for coliform analysis were done according to APHA Standard Methods by the membrane filtration technique. The grab sampling technique was employed for all sampling. Four sample sites were chosen in the Port Dalhousie beach area to determine what bacteriological or physical relationship the sites had to each other. The sample sites chosen were the sewage inflow to and the effluent from the St. Catharines (Port Dalhousie) Pollution Control Plant, Twelve Mile Creek below the sewage outfall and Lake Ontario at the Lakeside Park beach. The sewage outfall was located in Twelve Mile Creek, approximately 80 meters from the creek junction with the beach and piers on Lake Ontario. Twelve Mile Creek normally carried a large volume of water from the WeIland Canal which was diverted through the DeCew Generating Station located on the Niagara Escarpment. An additional sample site, which was thought to be free of industrial wastes, was chosen at Twenty Mile Creek, also in the Niagara Region of Ontarioo 3 There were marked variations in bacterial numbers at each site and between each site, but trends to lower_numbers were noted from the sewage inflow to Lake Ontario. Better correlations were noted between total and faecal coliform population levels and total phosphate P and ammonium N in Twenty Mile Creek. Other correlations were observed for other sample stations, however, these results also appeared to be random in nature. Salmonella isolations occurred more frequently during the winter and spring months when water temperatures were minimal at all sample stations except the sewage inflow. The frequency of Salmonella isolations appeared to be related to increased levels of total and faecal coli forms in the sewage effluent. However, no clear relationships were established in the other sample stations. Due to the presence of Salmonella and high levels of total and faecal coliform indicator organisms, the sanitary quality of Lake Ontario and Twelve Mile Creek at the sample sites seemed to be impaired over the major portion of the study period.

Families of the traumatically brian-injured : a case study approach to perceptions of quality of service, degree of satisfaction, and family needs /

The purpose of this qualitative research study was to foster an understanding of the rehabilitation counselling practice offamilies of the brain-injured. Specifically, the study explores the perceptions of stakeholders in regards to the degree of satisfaction with the quality of service received. Questionnaires were administered, and semi-structured, openended interviews were conducted, with six participating families (n=8). Preliminary data were collected via two instruments: (i) the Family Participant Questionnaire, consisting of participants' sample characteristics, information pertaining to the history of the family, details of the injury, and information relating to the type, use, and need offamily services utilized; and (ii) the Community Integration Questionnaire, a measurement of the degree of social displacementllevel of community integration of the injured family member. Utilizing the procedural steps outlined by Colaizzi's (1978) method of protocol analysis, recommendations for a future program based on related and current family needs are discussed in detail. Substantiating and supporting information are offered to rehabilitation practitioners, educational planners, and policymakers alike, concerning the degree of satisfaction with rehabilitative service, and the means of improving upon the overall quality of health care to families of the brain-injured. Implications for clinical practice and research are also raised for discussion.

A qualitative case study of the processes of peer education in a young adult tobacco control initiative, Leave the Pack Behind

Peer education involves peers offering credible and reliable information about sensitive life issues through the means of an informal peer group setting (Topping & Ehly, 1998). The purpose of this instrumental case study was to examine the processes of peer education through the exploration of two teams within a young adult tobacco control initiative, Leave the Pack Behind (LTPB). This qualitative case study examined two peer education teams over an eight-month period. Interviews, focus groups and observations were conducted with 12 participants across two peer education teams. Findings show the complexities of the processes of peer education including a connection between the stages of change and the changing role of the peer educator across stages of the empowerment process. Peer education teams and factors in the macro environment were also found to impact the process of peer education. This study provides a new definition for the process of peer education: peer education is a fluid process of knowledge exchange in which peer educators adopt different styles of facilitation as people move through stages of empowerment and change. This study contributes to the academic hterature upon the processes of peer education by providing a definition, a model and an overall understanding through an ecological and empowerment framework. The findings from this study suggest peer educators can be further trained to: use specific peer educational approaches that fit with student smoker's stage of change; better understand their position as a peer educator on the LTPB team; understand the reciprocal relationship between the macro environment and the peer education teams having an effect on one another.

Some ecological effects of beaver upon the watersheds in the Porcupine Hills, Alberta /

This ecological investigation of the beaver (Castor canadensis canadensis Kuhl) was part of the Eastern Slopes (Alberta) Watershed Research program conducted during the summers of 1968 . 1969 . 1970. and 1971 . A soil particle size analysis indicated that soil heavy with clay was used by the beaver for construction purposes in the Porcupine Hills . Examples were given of the beaver controlling erosion with the construction of dams . and also causing erosion to occur . However . in general . the beaver slow down soil erosion and decrease the loss of soil from this region. The beaver utilized measureable amounts of herbaceous vegetation . However, the utilization of herbs by the beaver requires further investigation. A system of ex~sures and enclosures of herbaceous vegetation plots was used to study the utilization of sedges , grasses , and forbs . The beaver indicated stronger species preference for willow as compared to aspen . The size preference for willow was in the 1.0 to 10.0 centimeters basal diameter classes , while the beaver utilization of aspen indicated a preference for the largest trees with basal diameter greater than 20.0 centimeters. Willow was the most important plant in the low lying areas with regard to distribution, abundance and to produce sustained yield. The beaver used this plant for food and construction throughout the study area. The distribution of aspen was limited. and this species did not appear to produce more than one crop in the lifetime of a beaver colony. Nine out of 15 woody plant types were sampled by the beaver in this region. A plot-intercept transect technique was used for systematic vegetation sampling of the woody vegetation in six intensively studied watersheds. The beaver population of the Porcupine Hills region of SW-Alberta is believed to depend upon the chinooks. During the 1971 ground census, a total of 60 active beaver colonies were tallied on the 930 square kilometers large study area. The beaver of the region were not found to store large food caches during fall and winter, however, they are believed to collect feed periodically throughout the winter months. It was observed that the severe winter in 1968-69, reduced by 27 per cent the number of active beaver colonies within the study area. The Porcupine Hills region had 0.07 beaver colony per square kilometer in 1971, a low density of beaver colonies due to the rough topography of the area. However, the importance of the beaver ponds was somewhat clarified as they provide increased moisture, which lessens the fire damage, and store water for wildlife and cattle in the area. Meteorological data was collected by the author in collaboration with the Department of Transport.

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.

Alicaligenes faecalis : identification and study of its antagonistic properties against Botrytis cinerea

A Gram negative aerobic flagellated bacterium with fungal growth inhibitory properties was isolated from a culture of Trichoderma harzianum. According to its cultural characteristics and biochemical properties it was identified as a strain of Alcaligenes (aeca/is Castellani and Chalmers. Antisera prepared in Balbc mice injected with live and heat-killed bacterial cells gave strong reactions with the homologous immunogen and with ATCC 15554, the type strain of A. taeca/is, but not with Escherichia coli or Enterobacter aerogens in immunoprecipitation and dot immunobinding assays. Growth of Botrytis cinerea Pers. and several other fungi was significantly affected when co-cultured with A. taeca/is on solid media. Its detrimental effect on germination and growth of B. cinerea has been found to be associated with antifungal substances produced by the bacterium and released into the growth medium. A biotest for the antibiotic substances, based on their inhibitory effect on germination of B. cinerea conidia, was developed. This biotest was used to study the properties of these substances, the conditions in which they are produced, and to monitor the steps of their separation during extraction procedures. It has been found that at least two substances could be involved in the antagonistic interaction. One of these is a basic volatile substance and has been identified as ammonia. The other substance is a nonvolatile, dialysable, heat stable, polar compound released into the growth medium. After separation of growth medium samples by Sephadex G-10 column chromatography a single peak with a molecular weight below 700 Daltons exhibited inhibitory activity. From its behaviour in electrophoretic separation in agarose gels it seems that this is a neutral or slightly positively charged.

Behavioural characteristics in phylogenetics : a case study using black fly (Diptera: Simuliidae) cocoon spinning behaviour

1-1 is torically, the predominan t method of reconstructing phylogenies has been through the use of morphological characters. There are new techniques now gaining acceptance, including molecular techniques al1d chromosomal information. Altl10ugh the study of behaviour has been used in a comparative framework, these analyses have, historically, been based on intuition. Hennig (1966) devised a neV\' method of reconstructing phylogenies which provided a 110ncircular method for formulating, testing and refining phylogenies. Subsequent s)Tstematists had virtually abandoned ecological and beha\lioural data as primary indicators of phylogenetic relationships (Brooks and McLennan 1991). Therefore, in a modern cladistic framework (sensu Hennig) the analysis of behavioural traits remains underrepresented as a method of reconstructing phylogenies. This thesis will reconstruct the phylogeny for species of black flies (Diptera: Simuliidae), using two steps. The first step is to thoroughl)' understand and explain the cocoon spinning in black fly larvae. There have bee115 previous descriptions of cocoon spinning, but all were incomplete or erroneous. The advances in technology, including video recorders and VCRs, have allowed this behaviour to be analyzed in great detail in 20 different species. A complete description of the cocoon spinning of Simulium \littatum is given. This description will be used as a template for the other species observed. The description and understanding of cococ)n spinning was the first step in undertaking a phylogenetic analysis using this behaviour. The behaviour was then broken down and analyzed, revealing 23 characters, 3 either qualitative and quantitative in nature. These characters were assessed in a cladistic framework (sensu Hennig) and a phylogenetic tree was reconstructed with a e.I of 0.91 and an R.I. of 0.96. This phylogenetic tree closely resembles a previously established pllylogenetic tree produced from morphological and cytological information. The importance of this result is the indication that, contrary to some authors, behavioural characters, if used properly, can add very informative characters to a data set.

Behavioural, mensural, and ecological correlates of polygyny in the eastern meadowlark (Sturnella magna)

During 1982 and 1983 I studied male attributes and attributes of the territory of male Eastern Meadowlarks (Sturnella magna) in order to determine whether there was a correlation between any of the attributes investigated and the number of females attracted by a male. Seventeen males, nine of which were polygynous and eight monogamous, were studied in 1982 and sixteen males.of which .. seven were polygynous and nine ~onogamous, were studied in 1983. The study was conducted in Short Hills Park, 10 km southwest of St. Catharines, Ontario and was designed to compare two hypotheses: the "sexy son" hypothesis (Weatherhead and Robertson,1977) and the polygyny threshold model (Verner and Willson,1966, Orians, 1969). Male attributes investigated were male size and song behaviour. Six measures of male size were taken: weight, flattened and natural wing chord length, culmen length, bill depth and length of the tarsometatarsus. In 1983 song repertoire size and song versatility measures were investigated. Attributes of the territory studied were: territory size, density of plant stems, percentage plant cover and measures of vegetation structure. In 1983 Arthropods were collected from each territory and sorted according to taxonomic group and size. During 1983, territory attributes were sampled twice, once early and once later in the nesting season. Analysis of data involved univariate comparisons between monogamous and polygynous males using T-tests and multivariate comparisons were made using discriminant function analysis (DFA) and principle components analysis (PCA).No correlations were found between the number of females attracted with, .ny measure of male size or with me, .sures of song versatili or size of song repertoire. Also no correlation was found between terri size and the number of females nesting on a terri . Some attributes of the male's terri id distinguish between monog,mous and po s males of thistudy. Analysis of Arthropod numbers showed that e~ .eran counts were significantly great~r on polygynous territories, a1 the total numb~rs of Arthropods collected showed no s fico .nt differences between territories of monogamous and po males. DFA chose ear teran and Hymenopteran counts as multivariate discriminators; both variables we' e more vegetation revealed that there were no univariate differences between the two groups of males fOT 1982 stem densities, but ~ spp. and Solidago spp. were chosen DFA as multivariate discriminators. The total number of plant stems and of Vicia spp. stems were s ficantly the early 1983 ing on monogamous territories for however DFA found no multivariate discriminators" Variables concerned with the overall aspects of vegetation structure showed significant differences between territories of monogamous and polygynous males. DFA of the 1982 sampling of vegetation structure showed significantly greater mat depth and vegetation height on polygynous territories, a finding which was not supported, however, by peA. For the early 1983 sampling period, plant height was greater on polygynous territories. Multivariate analysis identified greater green cover on polygynous territories, greater ground cover on monogamous territories, and greater depth of mat material on monogamous territories as discriminators between territories of monogamous and polygynous males. A DFA on the major variables of the study showed no significant difference between the territories of monogamous and polygynous male Meadowlarks. Of the correlations found, some were for non-prey Arthr~ods, for cover plants with very small samples sizes, or for variables which were greater for monogamous males during one sampling period and polygynous males during the next. While multivariate discriminators were found, peA showed no grouping of monogamous or polygynous males according to any of the variables investigated. On the basis of the univariate and multivariate analysis of major variables, I concluded that there were no correlations between the number of females attracted with male attributes and no unambiguous correlation with attributes of the territory. My study does not unequivocally support either the "sexy son" or the polygyny threshold hypothesis.

A time-resolved electron paramagnetic resonance spectroscopy study of paramagnetic porphyrins /

There is considerable interest in intramolecular energy transfer, especially in complexes which absorb visible light, because it is crucial to the better understanding of photoharvesting systems in photosynthetic organisms and for utilizing solar energy as well. Porphyrin dimers represent one of the best systems for the exploration of light-induced intramolecular energy transfer. Many kinds of porphyrins and porphyrin dimers have been studied over the past decade, however little attention has been paid to the influence of paramagnetic metals on the behavior of their excited states. In this thesis, Electron Paramagnetic Resonance Spectroscopy (EPR) is used to study such compounds. After light irradiation, porphyrins easily produce a variety of excited states, which are spin polarized and can be detected by the time-resolved (TR) EPR technique. The spin polarized results for vanadyl porphyrins, their electrostatically-coupled dimers, a covalently-linked copper porphyrin-free base porphyrin dimer, and free base porphyrins are presented in this thesis. From these results we can conclude that the spin polarization patterns of vanadyl porphyrins come primarily from the trip-quartet state generated by intersystem crossing (lSC) from the excited sing-doublet state through the trip-doublet state. The spin polarization pattern of electrostatically-coupled vanadyl porphyrin-free base porphyrin dimer is produced by the triplet state of the free base porphyrin half which is coupled to the unpaired electron on the vanadyl ion.

Distribution of excitation energy in photosynthesis: a study of heat loss, photo chemical activity and fluorescence emission in intact calls of cyanobacterium.

Photosynthetic state transitions were investigated in the cyanobacterium Synechococcus sp. PCC 6301 by studying fluorescence emission, heat loss, and PS I activity in intact cells brought to state 1 and state 2. 77K fluorescence emission spectra were modelled with a sum of 6 components corresponding to PBS, PS II, and PS I emissions. The modelled data showed a large decrease in PS II fluorescence accompanied with a small increase in the PS I fluorescence upon transition to state 2 for excitation wavelengths absorbed by both PBS and ChI ll.. The fluorescence changes seen with ChI .a. excitations do not support the predictions of the mobile PBS model of state transition in PBS-containing organisms. Measurements of heat loss from intact cells in the two states were similar for both ChI it. and PBS excitations over three orders of magnitude of laser flash intensity. This suggests that the PBS does not become decoupled from PS II in state 2 as proposed by the PBS detachment model of state transition in PBS-containing organisms. PS I activity measurements done on intact cells showed no difference in the two states, in contrast with the predictions of all of the existing models of state transitions. Based on these results a model for state transition In PBScontaining organisms is proposed, with a PS II photoprotectory function.

Active living in municipal parks and recreation : a case study

If quality of life is an important recreation outcome, then municipal parks and recreation management's efforts have to change because:· Over one-third of all the little kids in schools will be diabetic in their lifetime if the trends we are looking at continue. The average loss of life is about 15 years, and there is an average reduction in quality oflife by about 20 years (Jackson, 2007). This thesis is about municipal parks and recreation, an agency that controls and limits physical activity opportunity. It is also about active living; from an ecological perspective, a multi-disciplinary approach to incorporate physical activity into more 111 people's daily lives. In particular, this thesis examines one case --'. the Donutville Case - . with the intent of providing an explanation of how municipal parks and recreation can advance its management efforts to improve health outcomes of people suffering from daily physical activity deficits. More specifically, how can the tension between external and internal environments to municipal parks and recreation be better balanced to affect the change needed? Given that changing the current social reality is through making decisions, decision-making functions connected with systems theory helps identify how recreation authorities can more effectively influence environmental physical activity determinants. , Sallis et al.' (2006) ·social ecological model provides the a priori focus on active living decision-making. An integrated analogous emerging logic model is developed and presented as an efficacious strategy for how municipal parks and recreation decisionmakers can affect change. Keywords: physical activity, benefits outcomes, healthy livable community, quality of life, systems thinking, social ecological model, deci~ion-making, logic modeling, municipal parks and recreation, active living.

Study of new yeast strains as novel starter cultures for Riesling icewine production

Icewine is a sweet dessert wine fermented from the juice of grapes naturally frozen on the vine. The production of Icewine faces many challenges such as sluggish fermentation, which often yields wines with low ethanol, and an accumulation of high concentration of volatile acidity, mainly in the form of acetic acid. This project investigated three new yeast strains as novel starter cultures for Icewine fermentation with particular emphasis on reducing acetic acid production: a naturally occurring strain of S. bayanus/S. pastorianus isolated from Icewine grapes, and two hybrids between S. cerevisiae and S. bayanus, AWRI 1571 and AWRI 1572. These strains were evaluated for sugar consumption patterns and metabolic production of ethanol, glycerol and acetic acid, and were compared to the performance of a standard commercial wine yeast KI-VI116. The ITS rONA region of the two A WRI crosses was also analyzed during fermentations to assess their genomic stability. Icewine fermentations were performed in sterile filtered juice, in the absence of indigenous microflora, and also in unfiltered juice in order to mirror commercial wine making practices. The hybrid A WRI 1572 was found to be a promising candidate as a novel starter culture for Icewine production. I t produced 10.3 % v/v of ethanol in sterile Riesling Icewine fermentations and 11.2 % v/v in the unfiltered ones within a reasonable fermentation time (39 days). Its acetic acid production per gram sugar consumed was approximately 30% lower in comparison with commercial wine yeast K I -V 1116 under both sterile filtered and unfiltered fermentations. The natural isolate S. bayanus/S. pastorianus and AWRI 1571 did not appear to be suitable for commercial Icewine production. They reached the target ethanol concentration of approximately 10 % v/v in 39 day fermentations and also produced less acetic acid as a function of both time and sugar consumed in sterile fermentations compared to KI-V1116. However, in unfiltered fermentations, both of them failed to produce the target concentration of ethanol and accumulated high concentration of acetic acid. Both A WRI crosses displayed higher loss of or reduced copies in ITS rDNA region from the S. bayanus parent compared to the S. cerevisiae parent; however, these genomic losses could not be related to the metabolic profile.