Depuis une quinzaine d'années, de nombreuses galaxies sont détectées grâce à leur raie d'émission Lyman-alpha à des décalages spectraux supérieurs à 3. Ces objets, dits Émetteurs Lyman-alpha, nous permettent ainsi de sonder les galaxies dans l'Univers lointain, alors âgé de moins de deux milliards d'années. Bien qu'un grand nombre d'Émetteurs Lyman-alpha ait été détecté jusqu'à présent, leurs propriétés statistiques et physiques sont encore mal contraintes. En effet, les observations sont difficiles à interpréter du fait des effets de transfert résonnant des photons Lyman-alpha dans le milieu interstellaire et de la cinématique du gaz. En plus des observations, des efforts théoriques sont donc nécessaires pour mieux comprendre les caractéristiques physiques de ces objets, leur rôle dans le scénario de formation hiérarchique des galaxies, et leur lien avec l'autre grande populations de galaxies lointaines, les galaxies à discontinuité de Lyman. Cette thèse a pour but de proposer une modélisation originale de cette population d'Émetteurs Lyman-alpha dans le contexte cosmologique. La formation et l'évolution hiérarchique des galaxies est décrite grâce au modèle hybride GALICS, associant une simulation à N corps de matière noire, à des prescriptions semi-analytiques pour modéliser la physique des galaxies. GALICS prédit les propriétés physiques d'un large échantillon de galaxies entre z~3 et 7. Les propriétés de la raie Lyman-alpha sont obtenues grâce au couplage de GALICS avec une librairie de modèles numériques, réalisés avec le code MCLya. Avec cette approche, la fraction d'évasion des photons Lyman-alpha et le profil de la raie émergent des galaxies peuvent ainsi être prédits, en prenant en compte les effets de transfert résonnant des photons Lyman-alpha et la cinématique du milieu. Le modèle prévoit une forte dispersion de la fraction d'évasion des photons Lyman-alpha fesc en fonction de leur taux de formation stellaire. Les galaxies peu massives, formant peu d'étoiles ont une fraction d'évasion Lyman-alpha de l'ordre de l'unité. En revanche, fesc est distribué entre 0 et 1 pour les objets plus massifs, formant intensément des étoiles, selon les propriétés physiques des galaxies. Les résultats du modèle donnent un accord satisfaisant avec la plupart des observations, en particulier les fonctions de luminosité Lyman-alpha et UV entre z~3 et 7. Le modèle parvient à reproduire conjointement les propriétés UV des galaxies sélectionnées en UV (galaxies à discontinuité de Lyman) et celles des Émetteurs Lyman-alpha. Nous trouvons que les Émetteurs Lyman-alpha sont des galaxies de masse modérée présentant des profils de raie asymétriques, en bon accord avec les données observationnelles. Le modèle prévoit notamment une forte abondance de galaxies de faible luminosité Lyman-alpha. Ces objets peu lumineux seront une des cibles privilégiées du spectrographe intégral de champ MUSE, qui sera prochainement installé au VLT. Dans le but d'aider à la préparation des futurs relevés que MUSE effectuera, des champs fictifs d'Émetteurs Lyman-alpha ont été construits grâce au modèle pour fournir des prédictions, notamment en terme de comptages et de variance cosmique.

Yersinia enterocolitica are potentially pathogenic bacteria transmitted through the fecal oral route. Typical disease symptoms include those associated with gastrointestinal disease, although infection can also lead to more serious and invasive illnesses, particularly in sensitive populations. Previous surveys have detected Y. enterocolitica in surface water in various parts of the world, and studies have found drinking untreated water to be a possible risk factor for Y. enterocolitica infection. Methods available for the detection of Y. enterocolitica have been developed primarily for food and clinical samples and have not been tested extensively with water. More commonly used methods include culture based isolation of Yersinia spp. and polymerase chain reaction (PCR) based detection of Y. enterocolitica. Reports suggest that culture based methods available for the isolation of Y. enterocolitica may not be effective for environmental samples. Strain isolation using culture based methods is important, so that further subtyping information can be obtained for epidemiological investigations. In contrast, PCR based detection is more rapid, of higher throughput, can be highly specific and can target pathogenic strains within a species. The overall objective of this work was to evaluate culture based and PCR based methods for the detection of Y. enterocolitica in water, and to examine its prevalence in the Grand River watershed in Southwestern Ontario, Canada. Surface water in this watershed is used to provide all or part of the drinking water for approximately 500,000 people, as well as for recreational purposes. It is also one of the most heavily impacted watersheds in Canada by both agricultural and urban activities. Culture based studies compared two selective agars and four enrichment broths. Results showed that Cefsulodin Irgasan Novobiocin (CIN) agar and modified tryptic soy broth (mTSB) had greater potential for recovering Y. enterocolitica from surface water. Consequently, enrichment in mTSB followed by growth on CIN agar was used to isolate Yersinia from the Grand River. Yersinia strains were isolated from 52 out of 200 (26 %) surface water samples collected over a 17 month period. No seasonal trends were observed in isolation rates. Species isolated were typically considered to be non pathogenic species, although recent evidence suggests they may have potential virulence to humans. The majority of these strains have been found by other groups in surveys of aquatic environments. PCR methods developed targeted two Y. enterocolitica virulence genes: the ail gene, located in chromosomal DNA; and the yad A gene, located on a virulence plasmid. In surface water collected from the Grand River, the ail gene target was detected in 121 samples out of 319 (38 %) over a 29 month period and the yadA gene target was detected in 44 samples out of 206 (21 %) over a 20 month period. Both genes were detected more frequently when the water temperatures were colder. PCR-based studies conducted were quantitative, which has not previously been done with water samples. The median and maximum concentrations in samples positive for the ail gene were 40 and 2,000 cells/100 mL, and in samples positive for the yadA gene were 32 and 3,276 gene copies/100 mL, respectively. Overall results demonstrated that culture based methods are less sensitive than PCR based detection methods for specific detection of pathogenic Y. enterocolitica, suggesting that previous culture based surveys may have underestimated their potential prevalence. Furthermore, potentially pathogenic Y. enterocolitica may be present in the Grand River watershed. While Y. enterocolitica is relatively easily inactivated by traditional disinfection methods used in drinking water treatment processes, it is possible their presence poses a concern for recreational users and individuals drinking untreated water. This study suggests that further investigation is necessary to evaluate possible health risks associated with the occurrence of potentially pathogenic Y. enterocolitica in the Grand River. This work assists with the development of methods and information gathering for an emerging waterborne pathogen that has not been surveyed in the Grand River watershed, nor quantitatively surveyed in any water previously. Findings provide important information for drinking water providers and public health investigations.

Currently our understanding of both system and phytoplankton metabolism in large rivers is somewhat limited. Knowledge of the metabolic balance in such systems is necessary not only for proper management of the river itself, but also for the lakes into which they discharge. The River Continuum Concept proposes that the deep, turbid waters of large rivers have a poor light climate which leads to heterotrophic conditions (respiration > photosynthesis) yet this idea has been challenged. Similarly, it has been predicted that phytoplankton growth in large rivers is limited to areas of unusually favourable light climate and water retention (e.g. margins, backwaters), but the evidence is limited. Through longitudinal and diel measurements of Chl a, nutrient concentrations, dissolved oxygen and stable oxygen isotopes it was shown in this study that the lower Grand River was autotrophic during the two successive summers but either balanced or heterotrophic in other seasons. This implies that large rivers such as the Grand can be a transition zone for nutrients and a phytoplankton source, depending on season. Experimental incubations to measure oxygen production under varying irradiance demonstrated that phytoplankton could indeed grow (i.e., achieve positive net production) in the main river channel. Comparison of system and plankton metabolic rates further indicated that the phytoplankton were responsible for the major portion of the system production, but much less of the respiration. Sediment oxygen demand probably accounted for much of the additional respiration, but interactions with marginal and upstream habitats was probably an additional influence on both consumption and production of oxygen. The results further showed that stable oxygen isotope dynamics did not conform to the steady state model commonly used to infer metabolic patterns from environmental isotope data. A non-steady model was more successful and largely supported independent assessments of metabolism.

The first objective of this thesis was to predict the future success of selected tree species under low (B1, 550 CO2 ppm) and moderate (A1B, 720 CO2 ppm) climate change scenarios as defined in the Special Report on Emissions Scenarios (SRES). This was accomplished through the creation of radial-growth forecasts for eastern hemlock (Tsuga Canadensis (L.) Carr.), sugar maple (Acer saccharum L.), white spruce (Picea glauca (Moench.) Voss), and white pine (Pinus strobus L.) in the Grand River Watershed of Ontario, Canada. The forecasts were founded on historic growth-climate relationships between standardized regional dendrochronologies for each species and past climate data from the Guelph OAC weather station. These species-specific growth-climate relationships were then extended to 2100 using modeled climate data from the Third Generation Coupled Global Climate Model (CGCM3) to project radial-growth under both emissions scenarios. Results indicated that eastern hemlock radial-growth will remain stable throughout the 21st-century, sugar maple and white spruce growth will start to decline, and white pine growth will increase. While the radial-growth forecasts were limited by the length of the past climate data, the accuracy of the modeled climate data, and the number and type of variables used in the forecast model, the results were statically significant and strongly supported in the literature. The second thesis objective was to assess the potential impact of the radial-growth forecasts on environmental planning policy and forest management strategy in the Grand River Watershed. Examples of how the forecasts could influence basic management strategies in the watershed were provided to display the conceptual linkages between the results and policy formulation. Next, the radial-growth forecasts were presented to four forest managers working in the watershed to gage the practical implications, perceptions and limitations of the radial-growth forecasting method. While the managers found the radial-growth forecasts interesting, they also noted that the results were of limited use since they could not account for other factors important to the future success of the study species, such as seedling dispersal and establishment rates, as well as the potential effects of pathogens, insects and invasive species. Therefore, it was recommended that future research should work to extrapolate the results of the radial-growth forecasts to other tree species and types in the region, as well as incorporate more variables into the models, so that more accurate and applicable growth projections could be constructed in the watershed.

A numerical modelling analysis of climate change’s precipitation effects on the long-term, averaged surface and subsurface hydrology of the Grand River Watershed (GRW) was undertaken in order to assess possible areas of concern for decision makers in the water management sector. The physically-based, fully-integrated and variably-saturated 3-D surface-subsurface numerical simulator, HydroGeoSphere, was used to drive five mid-21st century climate change scenarios, developed from multiple general circulation models. Calibration involved altering measured and literature-derived hydraulic conductivity and precipitation distribution estimates, resulting in very good matching between observed and simulated long-term average surface flow at all gauge stations. Subsurface head results, too, matched observed heads quite well, though groundwater linkage to neighbouring watersheds was not included. When groundwater linkage to neighbouring watersheds was allowed, via regional Dirichlet boundary conditions used in a parent study, groundwater throughput was deemed to be unrealistic. All but one of the climate change scenarios caused an increase in both river discharge and water table elevation, with the greatest climate perturbations causing the greatest increases. For Scenario 1 (5% less precipitation than the 1960-to-1999 average), percentage discharge changes averaged -15% over all gauge stations. For the other scenarios (more precipitation than average), the inter-scenario discharge response ranged from approximately +12% to +59%. In general the range of inter-subcatchment response was greater than was the range for intra-subcatchment response; the greatest percentage response was consistently in the Speed River subcatchment, while the least was consistently in the Nith and Conestogo subcatchments. The exception was the application of less-than-average precipitation to the Grand River, whose gauge stations reported percentage changes in discharge that varied more substantially from one another. Subsurface hydrology reacted to the climate change scenarios in much the same manner as did the surface hydrology, with all climate change scenarios associated with a precipitation increase unsurprisingly resulting in higher total hydraulic heads throughout the entire domain. Specifically, the minimum and maximum mean head increases among the climate change scenarios were 0.41 m and 1.25 m respectively, while the only decrease was an average of 0.55 m. Similarly, the depth from the ground surface to the water table decreased in most scenarios, the maximum water table rise being 1.08 m and the minimum 0.36 m. When precipitation was allowed to decrease by 5% relative to the long-term average, the average water table elevation decreased by 0.48 m. However the water table’s pattern of high and low points remained very much the same among all climate change scenarios, suggesting that basin-wide groundwater flow patterns may not be among the hydrological measures most sensitive to climate change. Groundwater recharge, like almost all other components of the water budget, changed in linear proportion to the climate forcing and in agreement with GRW recharge estimates developed by others. Evapotranspiration, which met potential evapotranspiration in all scenarios due to the constant application of precipitation, was the only element of the water budget that did not increase, even though the water table was elevated closer to the rooting zone by most of the climate scenarios. On a smaller scale, changes in flow patterns may well be expected, given that zones of infiltration were observed to intensify with most of the climate forcing.

Municipal wastewater effluent (MWWE) has the potential for aquatic degradation, as it is the largest, per volume, anthropogenic discharge in Canada and other areas in the world. With an increasing population in many areas, such as Southern Ontario, there is concern that infrastructure of wastewater treatment facilities will not be able to maintain adequate treatment and prevent further degradation of the environment. The Grand River watershed, in Southern Ontario, is predicted to have its population increase to 1.2 million people by 2031 (from 780,000 people in 2001). Although wastewater treatment has improved, concern remains for receiving environments due to inadequate treatment (i.e. Kitchener) and minimal dilution (i.e. Guelph). This research was conducted to understand current impacts of MWWE in the Grand River watershed on fish communities to support future management and protection. Study sites upstream and downstream were chosen for their proximity to the Guelph, Kitchener, and Waterloo MWWE outfalls, similarity in habitat, and wadeability. Habitat analysis indicated that there were no large physical differences among sites. Fish communities were collected in a standardized method with a backpack electroshocker at each site (six randomly selected 10 m by 10 m sub-sites for 5 min). Greenside Darter (Etheostoma blennioides) and Rainbow Darter (E. caeruleum), the most abundant species, were also analyzed for stable isotope signatures (δ13C and δ15N) at each site. Downstream of the Guelph outfall there were no changes in mean total catch per unit effort (CPUE) or mean total mass. Changes to diversity, resilience, and tolerance in the fish community were attributed to a decreased abundance of Greenside Darter and increased abundance of Rainbow Darter. Downstream of the Kitchener discharge, there was a trend towards decreasing mean total CPUE, especially for darter species, and an increase in mean total mass due to a community shift to larger species including Catostomids and Centrarchids. The changes in abundance of Rainbow Darter, Catostomids, and Centrarchids among reference and Kitchener MWWE exposed sites explained the pattern in resilience, tolerance, and diet classifications. Lower diversity downstream of all three MWWE outfalls can be attributed to the increase in Rainbow Darter abundance. Stable isotope signatures (δ13C and δ15N) of Greenside Darter did not change downstream of the Guelph and Waterloo discharges, but signatures of Rainbow Darter increased immediately below the two outfalls. This shift may be due to the Rainbow Darter being able to take advantage of a change in the environment (i.e. food availability), resulting in its increased abundance and changes in isotopic signature. Directly downstream of the Kitchener outfall both darter species had an increase in δ13C and a large decrease in δ15N, likely due to high nutrient inputs from the outfall. The Kitchener wastewater discharge is also associated with a decrease in abundance of fish and a shift in community structure. MWWEs are currently affecting the aquatic environment, including fish communities in the Grand River watershed. Future investments in infrastructure and watershed management should be made to mitigate degradation of water quality in this watershed.

A series of deposits, located along the southern flanks of Grand Mesa, Colorado, and extending to the south, are problematic, and the processes related to emplacement are not understood. The overall area is dominated by two landform systems, Grand Mesa, which supported a Pleistocene ice cap, and the North Fork Gunnison River drainage. Thus, one has to ask: Are these deposits the result of the melting of the ice cap or are they fluvial terraces associated with the evolution of the ancestral Gunnison River? The goal of this research was to map the areal extent of the deposits and to interpret the formation and climatic significance in understanding the evolution of the Pleistocene landscape in the region. An extensive exposure, parallel to State Highway 65 near Cory Grade, was used for detailed description and sampling. Three additional exposures, ~10 to 20 km (~6 to 12 mi) were used to extend the areal extent of sampling. The study area was mapped using aerial photography and traditional field mapping aided by GPS. From the field work, a detailed stratigraphic column, including lithology and erodability, was constructed. Vertical exposures of the deposits were described, mapped, and recorded in the field and using detailed photo mosaics. Samples were collected from each stratum of the deposits for grain-size, shape, and sorting analyses. Five distinct depositional facies were identified. Sieve analysis on collected samples shows that four distinct grain-sizes occur in the outcrops; coarse sand, very-coarse sand, granule, and pebble and boulder. Mean grain-sizes range from 0.0722 to 0.9617, -0.0948 to -0.9456, -1.0566 to -1.9053, and -2.0050 to -3.4643, respectively. Glacio-fluvial depositional environments were identified and supported with observations of sedimentary structures and clast composition. Two major environments of deposition are recorded in the deposits; fluvial deposits from glacial outburst floods, and debris flow deposits. Imbrication of clasts in the strata suggests the flow came from the direction of Grand Mesa to the north. Facies and subsequent sequences were constructed to portray evidence that supports the glacio-fluvial mode of deposition.

After 911 happened,cause the global shocked,not only change the terrorism attack forms and way,but also broken mythology the Unite States native land won¡¦t be attacked by others. Terrorism violence attack is the global faced the question of the 21th,it will influence on U.S government and people life,also its friend countries and global stability.The U.S had went Through 911 event ,it¡¦s as soon as positive thinking to adjust post-cold-war period of war-strategy and to search of global military deploy, its hopes to solve religioue ,Racial, culutural, and territorial conflict, and then to finish extreme racialism, religionism terror attack event. Because of terrotorism violence actions was directed hit the U.S and friend countries benefit,the global anti-terrorism war-strategy of structural had emerged. Therefore, how to prevent and restrict terror attacks event happening again,it will to be trial and challenge the Unite States government and global anti-terrorism war- stratege conduct of actions and reaction.

In this master study, the sustainability of local craftsmanship as affected by trust and work ethic will be discussed in the specific case of the jewelry sector in the Grand Bazaar. The case study is presented relying on interviews. The research theme is evaluated in sub-categories which contain socio-demographic structure, work ethic of masters and apprentices, Grand Bazaar and the jewelry sector. The effects of trust, work ethic, and obedience on craftsmanship are discussed. Basically, informal relations form the foundation for the work and trade relations especially in craft based jewelry sector. The Grand Bazaar in Istanbul was chosen because it is the most important place for the craft-based jewelry sector in Turkey. This study first poses a general question by asking whether or not the jewelry sector in Istanbul (the Grand Bazaar) is still a craft. The analysis of the concepts of trust, work ethic, obedience, and social networks are operationalized and provide the frame for the main examination. The investigation of this topic will give clues about the organizational structure, working conditions of sector members and the production process of the sector. In the first part of this study, the concept of craftsmanship is described. This is done by giving special reference to the concepts of artisanal knowledge and work ethic. The discussion is settled in a short analysis of globalization processes. The past and future of the jewelry sector in the Grand Bazaar and guild system is discussed. In the second part, the case study is presented, relying on interviews with craftsmen in the jewelry sector in the Grand Bazaar.

This study is an attempt to explore the multifarious aspects of Karl Friedrich Schinkel