No

<p> During the summer of 1970 a study was initiated to define factors controlling the biosphere in the lentic environment of the Precambrian Shield. Data were collected from nine lakes of varying size and depth located in a number of geological formations. Chemical, physical and biological conditions in these lakes were investigated at two sampling periods and the lakes were classified on the basis of morphology (surface area to volume area) and lithology (surficial and bedrock geology). Attempts were made to determine the influence of morphology and lithology on the chemical and biological conditions observed. Emphasis was placed on the relationships of these factors to aspects of the primary and secondary trophic levels in the lentic ecosystem including primary productivity and the standing crop and diversity of phytoplankton and zooplankton.</p> <p> The atmosphere, a third potential factor influencing lakes was investigated by means of a network of air monitoring stations (collecting both precipitation and 'dry fallout') located throughout the greater Sudbury area.</p> <p> The results of the study indicated that: 1. the lentic ecosystem in the Precambrian Shield area studied can be defined by simple chemical and physical variables. 2. the morphology of the lake basins (surface area to volume ratio) modified by lithology (primarily the presence or absence of limestone) is the major factor influencing biological activity. Lakes with a low surface area to volume ratio showed low productivity while lakes with a high surface area to volume ratio showed nigh productivity. Silica and calcium concentrations (influenced by the lithosphere) were important since relatively small changes in the concentration of these chemical species stimulated a response in the biosphere. 3. some of the lakes were affected by concentrations of sulphates conveyed to the water by the atmosphere. Observed effects included increases in the hydrogen ion concentration in lakes with low calcium concentrations (poorly buffered) and a depression of the diversity of both primary and secondary trophic levels.</p> / Thesis / Master of Science (MSc)

The deformation associated with a ballistic shield defeating a projectile can interact with the user’s upper extremity, resulting in the release of the shield, placing those behind the device at risk. This injury mechanism is known as behind-shield blunt trauma (BSBT). Previous studies investigating these interactions have used testing conditions not representative of those present during these behind-shield events and lacked sufficient testing to determine statistically relevant outcomes. In the present work, the loading present during ballistic shield deformation was characterized through testing using an Anthropomorphic Test Device (ATD) upper extremity placed behind a level III ballistic shield. Digital image correlation (DIC) and post-impacting X-ray imaging were used to assess the ballistic shield’s deformation. The data collected from ballistic testing informed the development of a projectile used with a pneumatic impactor for the application of BSBT in a lab-based setting. Using the projectile, ballistic impacts were replicated on the ATD upper extremity and translated to 5th and 95th percentile cadaveric arms. Load data were collected for the hand and forearm using piezoelectric force sensors embedded in the projectile. Similarly, PMHS were impacted in a stepwise fashion of increasing energy until fractures were identified using X-ray imaging. A novel scaling technique was developed where Partial Least Squares (PLS) was used to determine critical variables relating donor anthropometrics to peak impact force. The scaling equations generated using this technique offer future researchers the opportunity to employ a larger range of specimens when determining injury thresholds for the hand and forearm. Through the characterization of the conditions present during BSBT, the injury thresholds to these mechanisms were assessed for understudied populations. Additionally, this work presents scaling techniques that could reduce the number of specimens required to determine future upper extremity injury limits. The information presented within this work provides an important step in developing new standards for ballistic shields to better protect users from BSBT. / Thesis / Master of Applied Science (MASc) / The deformation of a ballistic shield associated with stopping a bullet can interact with the user’s arm, causing them to drop the shield and placing the user in further danger. This work aimed to assess the risks to the hand and forearm over a range of male sizes using mechanical and biomedical tools. Ballistic loading was characterized using a crash test dummy arm to understand the conditions present during the event. The injuries associated with this loading were assessed using cadaveric specimens and a custom projectile for replicating the impacts. Mathematical techniques were used to translate the injury thresholds to the exact user sizes – providing relevant metrics for future ballistic shield standards. The results of this work present methods for recreating ballistic testing in a lab-based setting and for scaling forces associated with the hand and forearm, allowing future researchers to use a broader range of specimens for injury assessment.

No description available.

The effect of lake acidification was evaluated, in the field, in terms of its impact on both the structural and functional composition of the macrozoobenthic community. The littoral macrozoobenthic community and water chemistry of 45 Canadian Shield lakes was sampled. The water chemistry variables sampled included pH, total dissolved calcium, conductivity, and dissolved organic acid (measured as colour). Partial canonical correlation analysis and partial regression analysis were used to identify those components of the macrozoobenthic community that most directly reflected pH variability. This was done by first removing from the data that portion of the variability attributable to total dissolved calcium, conductivity, and dissolved organic acids. In addition, the spatial structure in the data was removed by identifying the geographic coordinates of the sampling sites. / In general, the results presented here are not consistent with previous studies where the response of the macrozoobenthic community was related to pH without consideration of confounding covariables. Snails, leeches, mayflies and crayfish have all been cited for their sensitivity to acidification. The present study found these taxa to reflect, not pH variability, but rather attributes of water hardness. Similar results were found for both total zoobenthic biomass and functional feeding group abundance.

Herrenknecht AG is a German world-leading Tunnel Boring Machines manufacturer showing strong awareness and concern regarding environmental issues. The company supports research on the Energy Efficiency (EE) of their products, aimed at the development of intelligent design for a green Tunnel Boring Machine. The aim of this project is to produce a ’status quo’ report on EE of three types of Tunnel Boring Machines (Hardrock, EPB and Mixshield TBM). In the framework of this research 39 projects are analysed using calculation tools, plotting and statistical functionalities of Excel and Matlab. The findings of this study inter alia confirm the existence of data quality issue and highlight the necessity of data quality control, allow identification of specific distinctions between energy consumption of the three investigated TBM types, and stress the necessity for optimisation of the layout of TBMs energy supply units and main consumers. Moreover the results of the survey suggest that there is a certain energy saving potential, which is achievable by e.g. an adequate selection of the machine type prior to start of a given project and better adjustment of the machines’ layout to the particular local geological environments. An EE implementation strategy, indicating further research needs, is suggested and discussed.

No description available.

This thesis deals with parental care of invertebrates. I focus on its types, forms and examples of species in which it occurs. I worked out in more detail the care of the offspring of true bugs (Heteroptera) family Acanthosomatidae and focused on the observation, collection and study of a particular kind Elasmucha grisea in insectarium and nature.

Este estudo tem por objetivo formular um composto cerâmico para revestimento de paredes visando contribuir para a otimização da blindagem de salas de diagnóstico. O trabalho foi baseado em medidas experimentais de atenuação da radiação X (80 e 100 kV) empregando materiais cerâmicos de revestimento contendo diferentes suportes cerâmicos (vermelho, branco, grês, porcelanatos, etc). Dentre os suportes cerâmicos avaliados, o grês branco apresentou melhores propriedades atenuadoras, e foi considerado o mais adequado para a proposta deste trabalho. Diferentes formulações de grês branco foram estudadas e alteradas a fim de obter melhores propriedades atenuadoras. Foram efetuadas simulações de composições cerâmicas de revestimento grês dentro das porcentagens de matérias-primas necessárias na composição que são 12-20% argila; 6-18% caulim; 12-25% filito; 8-14% quartzo; 10-18% feldspato; 32- 40% pegmatito; 6-8% talco. As composições químicas quantitativas e qualitativas destes materiais foram também avaliadas, e os elementos constituintes mais comuns são SiO2, Fe2O3, Al2O3, CaO e Ti2O3. Considerando que o CaO pode ser substituído pelo PbO ou BaO, foram estudadas formulações com maiores teores de óxidos de Pb e Ba. O comportamento destes materiais como atenuadores para a radiação X foi investigado por meio de simulações computacionais que levaram em consideração os espectros de raios X incidentes e transmitidos através das diferentes composições estudadas e comparado com os materiais de referência Pb, Ba e BaSO4 (barita). Os resultados obtidos nas simulações indicaram as formulações do composto de suporte cerâmico grês que demonstram melhores propriedades de atenuação levando-se em conta as energias usadas em raios X diagnóstico (80, 100 e 150 kV). Placas cerâmicas baseadas na composição formulada que apresentou menor diferença percentual em relação ao Pb foram produzidas em laboratório e testadas fisicamente como revestimento de parede e barreira protetora. Propriedades como módulo de resistência à flexão, densidade, carga de ruptura, absorção de água e atenuação da radiação X foram avaliadas para todas as placas produzidas. / This study aims to formulate a ceramic composition for wall coating seeking to contribute to the optimization of diagnosis rooms’ shielding. The work was based on experimental measures of X-radiation attenuation (80 and 100 kV) using ceramic coating materials containing different ceramic bases (red, white, grês, stoneware porcelain tiles, etc). Among the appraised ceramic bases, the white grês presented better attenuation properties and it was considered the most suitable material for the targets of this work. Different formulations of white grês were studied and altered in order to obtain better attenuation properties. Simulations of ceramic compositions using grês coating were made maintaining the percentages of 12-20% clay; 6-18% kaolin; 12-25% phyllite; 8-14% quartz; 10- 18% feldspar; 32-40% pegmatite and 6-8% talc in the composition of the necessary raw-material. The quantitative and qualitative chemical compositions of these materials were also evaluated and the most common representative elements are SiO2, Fe2O3, Al2O3, CaO and Ti2O3. Formulations containing Pb and Ba oxides were studied, considering that CaO can be replaced by PbO or BaO. The attenuation properties for X-radiation were investigated by computer simulations considering the incident and transmitted X-ray spectra for the different studied compositions and they were compared to the properties of the reference materials Pb, Ba and BaSO4 (barite). The results obtained with the simulations indicated the formulated composition of grês ceramic base that presented better attenuation properties considering the X-ray energies used in diagnosis (80, 100 and 150 kV). Ceramic plates based on the formulated compositions that presented lower percentage differences related to Pb were experimentally produced and physically tested as wall coating and protecting barrier. Properties as flexion resistance module, density, load rupture, water absorption and Xradiation attenuation were evaluated for all produced plates.

Este estudo tem por objetivo formular um composto cerâmico para revestimento de paredes visando contribuir para a otimização da blindagem de salas de diagnóstico. O trabalho foi baseado em medidas experimentais de atenuação da radiação X (80 e 100 kV) empregando materiais cerâmicos de revestimento contendo diferentes suportes cerâmicos (vermelho, branco, grês, porcelanatos, etc). Dentre os suportes cerâmicos avaliados, o grês branco apresentou melhores propriedades atenuadoras, e foi considerado o mais adequado para a proposta deste trabalho. Diferentes formulações de grês branco foram estudadas e alteradas a fim de obter melhores propriedades atenuadoras. Foram efetuadas simulações de composições cerâmicas de revestimento grês dentro das porcentagens de matérias-primas necessárias na composição que são 12-20% argila; 6-18% caulim; 12-25% filito; 8-14% quartzo; 10-18% feldspato; 32- 40% pegmatito; 6-8% talco. As composições químicas quantitativas e qualitativas destes materiais foram também avaliadas, e os elementos constituintes mais comuns são SiO2, Fe2O3, Al2O3, CaO e Ti2O3. Considerando que o CaO pode ser substituído pelo PbO ou BaO, foram estudadas formulações com maiores teores de óxidos de Pb e Ba. O comportamento destes materiais como atenuadores para a radiação X foi investigado por meio de simulações computacionais que levaram em consideração os espectros de raios X incidentes e transmitidos através das diferentes composições estudadas e comparado com os materiais de referência Pb, Ba e BaSO4 (barita). Os resultados obtidos nas simulações indicaram as formulações do composto de suporte cerâmico grês que demonstram melhores propriedades de atenuação levando-se em conta as energias usadas em raios X diagnóstico (80, 100 e 150 kV). Placas cerâmicas baseadas na composição formulada que apresentou menor diferença percentual em relação ao Pb foram produzidas em laboratório e testadas fisicamente como revestimento de parede e barreira protetora. Propriedades como módulo de resistência à flexão, densidade, carga de ruptura, absorção de água e atenuação da radiação X foram avaliadas para todas as placas produzidas. / This study aims to formulate a ceramic composition for wall coating seeking to contribute to the optimization of diagnosis rooms’ shielding. The work was based on experimental measures of X-radiation attenuation (80 and 100 kV) using ceramic coating materials containing different ceramic bases (red, white, grês, stoneware porcelain tiles, etc). Among the appraised ceramic bases, the white grês presented better attenuation properties and it was considered the most suitable material for the targets of this work. Different formulations of white grês were studied and altered in order to obtain better attenuation properties. Simulations of ceramic compositions using grês coating were made maintaining the percentages of 12-20% clay; 6-18% kaolin; 12-25% phyllite; 8-14% quartz; 10- 18% feldspar; 32-40% pegmatite and 6-8% talc in the composition of the necessary raw-material. The quantitative and qualitative chemical compositions of these materials were also evaluated and the most common representative elements are SiO2, Fe2O3, Al2O3, CaO and Ti2O3. Formulations containing Pb and Ba oxides were studied, considering that CaO can be replaced by PbO or BaO. The attenuation properties for X-radiation were investigated by computer simulations considering the incident and transmitted X-ray spectra for the different studied compositions and they were compared to the properties of the reference materials Pb, Ba and BaSO4 (barite). The results obtained with the simulations indicated the formulated composition of grês ceramic base that presented better attenuation properties considering the X-ray energies used in diagnosis (80, 100 and 150 kV). Ceramic plates based on the formulated compositions that presented lower percentage differences related to Pb were experimentally produced and physically tested as wall coating and protecting barrier. Properties as flexion resistance module, density, load rupture, water absorption and Xradiation attenuation were evaluated for all produced plates.