The existence of anchor ice in supercooled water can have a profound impact on the management of water resource infrastructures in cold regions. For example, it can raise a tailrace water level and cause significant losses in generation revenue. So far, there have been limited studies on anchor ice, therefore, many problems still exist and much more study is needed. In the present research, experimental and mathematical studies of anchor ice were carried out. Experiments were conducted in a counter-rotating flume, located in a cold room at the University of Manitoba. The experiments were mainly focused on anchor ice evolution around rocks and on gravel beds under different hydro-meteorological conditions. The results are compared to a mathematical model developed herein and some important parameters such as anchor ice porosity and frazil ice deposition coefficient are examined. The growth process of anchor ice was monitored by two CCD cameras. A digital processing program was developed to analyze anchor ice images and determine the growth rate of anchor ice. In addition, anchor ice density, an important factor when studying anchor ice, was estimated and the effect of air temperature, Froude number and Reynolds number is explored. By analyzing torque load signals from the counter-rotating flume, the variation of bed roughness with the growth of anchor ice is elucidated. The deposition coefficient of anchor ice growth was also determined from the experiments. A mathematical model was developed based on a two-stage method to simulate the process of frazil ice transportation and deposition. Both frazil ice attachment and heat transfer between the supercooled water and ice crystals are considered in the model. Four governing equations related to the distribution of velocity and frazil ice transportation and deposition inside and outside the roughness layers were built. A fourth-order Runge- Kutta numerical method was used and programmed in Matlab to solve the governing equations. The growth rate of anchor ice under different hydro-meteorological conditions can be simulated by this numerical model. The proposed experimental and mathematical studies of anchor ice are presented intuitively in this paper and the results from this study contribute to a better understanding of the anchor ice growth mechanism. This study will help to develop better management strategies to mitigate ice related complications associated with hydroelectric generating stations and other hydraulic structures in cold regions.

The aim of this study was investigate if increasing total organic carbon (TOC) affects the growth rate and biomass of perch (Perca fluviatilis) and biomass of roach (Rutilus rutilus). The ongoing climate change affects the climate by increasing annual mean temperature and precipitation. The runoff to surface waters will increase, which also has the consequence that the export of terrestrial organic matter (TOM) and nutrients to surface waters will increase. Increasing of TOM into the surface waters make it darker, i.e. brownification of the water. This brownification of surface water affects the amount of available light for benthic algae causing the benthic primary production to decrease. As the benthic primary production decreases also whole lake ecosystem productivity decreases. The impact on fish biomass and production of fish were studied in five small lakes in Sweden. Lake morphology, water chemistry and fish community characteristics were sampled. A subset of perch from the catch was selected to determine age and growth. Data from age determination was then used to calculate the size dependent growth and production of perch in each lake. Total fish biomass and biomass of perch and roach was negatively affected by TOC and yearly biomass production of perch was lower in lakes with higher TOC. Thus, climate change may at least in small forest lakes lead to lower production and biomass of fish in the future.

The existence of anchor ice in supercooled water can have a profound impact on the management of water resource infrastructures in cold regions. For example, it can raise a tailrace water level and cause significant losses in generation revenue. So far, there have been limited studies on anchor ice, therefore, many problems still exist and much more study is needed. In the present research, experimental and mathematical studies of anchor ice were carried out. Experiments were conducted in a counter-rotating flume, located in a cold room at the University of Manitoba. The experiments were mainly focused on anchor ice evolution around rocks and on gravel beds under different hydro-meteorological conditions. The results are compared to a mathematical model developed herein and some important parameters such as anchor ice porosity and frazil ice deposition coefficient are examined. The growth process of anchor ice was monitored by two CCD cameras. A digital processing program was developed to analyze anchor ice images and determine the growth rate of anchor ice. In addition, anchor ice density, an important factor when studying anchor ice, was estimated and the effect of air temperature, Froude number and Reynolds number is explored. By analyzing torque load signals from the counter-rotating flume, the variation of bed roughness with the growth of anchor ice is elucidated. The deposition coefficient of anchor ice growth was also determined from the experiments. A mathematical model was developed based on a two-stage method to simulate the process of frazil ice transportation and deposition. Both frazil ice attachment and heat transfer between the supercooled water and ice crystals are considered in the model. Four governing equations related to the distribution of velocity and frazil ice transportation and deposition inside and outside the roughness layers were built. A fourth-order Runge- Kutta numerical method was used and programmed in Matlab to solve the governing equations. The growth rate of anchor ice under different hydro-meteorological conditions can be simulated by this numerical model. The proposed experimental and mathematical studies of anchor ice are presented intuitively in this paper and the results from this study contribute to a better understanding of the anchor ice growth mechanism. This study will help to develop better management strategies to mitigate ice related complications associated with hydroelectric generating stations and other hydraulic structures in cold regions.

Blue-flowered Conospermum are endemic to Western Australia, and show great potential as cut flowers. Propagation from cuttings or seed proved difficult, and root initiation in vitro is problematic. This thesis examines the floral biology of the species and the possibility of using somatic embryogenesis to overcome propagation problems. A survey of explant tissue types for C. eatoniae and C. caeruleum was carried out to identify tissue that could be induced into embryogenic pathways. Vegetative, semi-floral and floral buds were initiated into culture from February to June, but were found unsuitable for embryogenesis, producing shoots, callus or dying in culture. Leaves from in vitro leaf cultures formed callus in the presence of 2,4-D and BAP, but were unable to differentiate into embryos in the presence of a variety of growth regulator combinations and concentrations. Immature zygotes died in culture. Direct embryogenesis and/or embryogenic callus was observed on mature zygotes of the species C. caeruleum, C. spectabile, C. dorrienii and C. brownii, and somatic embryos were maintained in culture for up to 18 months for C. caeruleum. Maturation and germination of somatic embryos proved difficult; treatments of cold, ABA, desiccation or mannitol did not induce maturation. It appears that developmental pathways in Conospermum are well defined and are difficult to alter in vitro. It was concluded that somatic embryogenesis has limited commercial potential in these species. Conospermum species have an active pollination mechanism where the style is held in a state of tension when the flower opens. When pressure is applied at the base of the style by an insect, the style flicks downwards, striking the insect pollinator and releasing pollen from the anther in a single dusty mass. However, the breeding systems of blue-flowered Conospermum have not previously been well explored. Flowers on a C. eatoniae inflorescence opened from the basal end upwards acropetally, with the terminal two or three buds never opening. Fruit and seed set occurred only from the basal one to three buds. Isolation of C. eatoniae and C. amoenum flowers showed they were unable to self-pollinate in the absence of insect pollinators. Experiments to determine the timing of the peak of stigmatic receptiveness were inconclusive. Pollen germinated and penetrated the stigma 0 ¡V 6 days after anther dehiscence. Pollen loads on the stigma did not relate to the number of pollen tubes observed down the style. Controlled pollinations of cultivated C. eatoniae at a field station using self and cross pollen, revealed compatibility with a range of pollen genotypes, as pollen tubes were observed extending down the style. However, late-acting incompatibility could not be ruled out as controlled crosses failed to set any seed as flowers were shed from the bush. DNA analysis of open pollinated C. eatoniae seed progeny from two plants from a field station and two plants in natural bushland revealed very different pollination habits. Plants from the field station showed no outcrossing, with progeny closely resembling the maternal parent, whereas plants from the wild population showed outcrossing with several different paternal parents. These results suggest self-pollinated seed can be reliably obtained in a plantation situation using stands of ramets of the same clone. Alternatively, assuming that the required insect pollinators are present in a cultivated stand, it should be possible to obtain cross pollinated seed by surrounding the maternal plant with the desired paternal parent. Unusual pollen behaviour was observed for many blue-flowered species, a white-flowered species of Conospermum, and close relative, Synaphea petiolaris. Up to three pollen tubes emerged from the triporate pollen in vitro, and at rates of up to 55 ƒÝms-1. This rate was maintained for only 2 s but is greater than 20 times faster than reported in the literature for any species, in vitro or in vivo. Pollen with multiple tubes was also observed on the stigma in vivo in C. amoenum flowers. Changing the osmotic pressure of the germination medium by altering sucrose concentration influenced the number of tubes to emerge from the pollen grain; generally the number of tubes decreased as sucrose increased. However, the rate of tube growth was unaffected. The addition of calcium channel blockers to the germination medium had no effect on Conospermum growth rate, nor did they eliminate pulses of tube growth. Observation of Conospermum pollen ultrastructure revealed similarities to Gramineae pollen. The tube cytoplasm was packed with vesicles filled with material of similar electron density to the cell wall. Few golgi were identified, and the apical end of the tube contained these vesicles, smaller secretory vesicles and mitochondria. This is atypical of the tip, which is normally free of large vesicles. Distinct zones in the cytoplasm were not identified, which is similar to Gramineae. Like the grasses, Conospermum appears to pre-manufacture cell wall material and store it in vesicles ready for rapid germination and extension. A biological function of multiple pollen tube emergence with such rapid growth was not elucidated. This research has shown Conospermum to be a complex and very interesting genus. Further investigation into the remarkable growth of multiple pollen tubes would enhance our knowledge of the biological processes involved in tube growth and the process of fast wall formation. The potential benefits to the cut flower industry of commercialising some of these species warrants further effort to find an efficient method of propagation. Introduction into horticulture may be the only means by which these threatened species will survive.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Introdução: Estudos vêm demonstrando que o ambiente intrauterino influencia no crescimento fetal e extrauterino, repercutindo no perfil de saúde em longo prazo. Objetivo: Comparar a velocidade de crescimento durante os primeiros três meses de vida de crianças geradas em ambientes intrauterinos considerados adversos. Métodos: Trata-se de um estudo longitudinal prospectivo controlado desenvolvido com pares de mãe-filho residentes em Porto Alegre/RS. Cinco grupos de exposição foram estudados (diabetes, hipertensão arterial, tabaco e restrição do crescimento intrauterino) e um controle. O crescimento foi avaliado em cinco momentos (pós-parto, sete dias, quinze dias, um mês e três meses) utilizando os índices peso para idade (P/I), comprimento para idade (E/I) e Índice de Massa Corpórea para idade (IMC/I). A análise de regressão Equações de Estimativas Generalizadas foi utilizada para avaliar a relação entre o ambiente intrauterino e o crescimento. A velocidade de crescimento foi avaliada com um e três meses, utilizando a diferença entre as medidas de escore z (delta). Identificou-se a influência de fatores sociodemográficos, maternos e neonatais no peso ao nascer e na velocidade de crescimento. Resultados: Os fatores que influenciaram no peso ao nascer foram: paridade, IMC pré-gestacional, ganho de peso durante a gestação, tipo de parto e sexo. Ao utilizar o escore z de P/I, verificou-se que os grupos tabaco e restrito apresentaram médias significativamente menores do que o controle. De zero a um mês, a velocidade de ganho de peso entre os restritos foi significativamente maior do que os demais. De zero a três meses, só não foi significativamente maior do que o grupo hipertensão arterial. A velocidade de ganho de comprimento de zero a um e de zero a três meses foi significativamente maior no grupo restrito ao comparar com o controle. Ao utilizar o escore z de IMC/I, os grupos tabaco e restrito apresentaram médias significativamente menores do que o grupo controle. A velocidade de ganho de IMC de zero a um mês do grupo restrito só não foi significativamente maior do que o grupo hipertensão arterial. De zero a três meses, foi significativamente maior do que todos os demais. Os fatores que influenciaram na velocidade de crescimento foram: situação conjugal, IMC pré-gestacional, ganho de peso durante a gestação e internação hospitalar da criança. Conclusão: O presente estudo identificou que a velocidade de crescimento nos três primeiros meses de vida é influenciada por ambientes intrauterinos adversos e diferentes fatores gestacionais e neonatais estão envolvidos neste contexto. O grupo restrito foi o que apresentou os escores médios mais baixos e a maior recuperação. O grupo hipertensão arterial, que possuiu escores médios negativos, apresentou velocidade de ganho de peso positiva durante os primeiros três meses, sinalizando recuperação. Já o grupo tabaco, que apresentou escores médios negativos, não possuiu recuperação significativa. Os achados deste estudo poderão auxiliar na elaboração de estratégias de prevenção do crescimento acelerado em crianças expostas a fatores considerados de risco. Intervenções realizadas na infância inicial poderão refletir no perfil de saúde e na carga de doenças durante o curso da vida destas crianças. / Introduction: Studies has demonstrated that the intrauterine environment influences on fetal and extrauterine growth, reflecting the long-term health profile. Objective: To compare the growth velocity during the first three months of life among children born in intrauterine environments considered adverse. Methods: It is a prospective controlled longitudinal study developed with mother-infant pairs living in Porto Alegre/RS. Four exposure groups were studied (diabetes, hypertension, smoking and intrauterine growth restricted) and a control. Growth was evaluated in five moments (postpartum, seven days, fifteen days, one month and three months) using the weight for age (W/A), height for age (H/A) and Body Mass Index for age (BMI/A). Regression analysis with generalized estimating equations were used to evaluate the relationship between the intrauterine environment and growth. The growth velocity was performed with one and three months using the difference between the z-score measures (delta). Were identified the influence of sociodemographic factors on maternal and neonatal birth weight and growth velocity. Results: Factors that influence the birth weight were: parity, pre-pregnancy BMI, weight gain during pregnancy, type of delivery and sex. By using the z score for W/A, it was found that tobacco and intrauterine growth restricted groups had significantly lower average than the control. From zero to one month, the weight gain velocity between intrauterine growth restricted was significantly higher than the others. From zero to three months, weight gain velocity of the intrauterine growth restricted group was significantly higher than the other groups, except hypertension. The length gain velocity from zero to one and three months was significantly higher in the intrauterine growth restricted vs. control. By using the BMI/A z score, tobacco and intrauterine growth restricted groups had significantly lower average than the control group. From zero to one month, only BMI gain speed intrauterine growth restricted group was not significantly higher than the hypertension group. From zero to three months, was significantly higher than the others. The factors that influenced the growth velocity were: marital status, pre-pregnancy BMI, weight gain during pregnancy and the child's hospitalization. Conclusion: The present study identified that the growth velocity in the first three months of life is influenced by adverse intrauterine environment and different gestational and neonatal factors are involved in this context. The intrauterine growth restricted group was the one with the lowest average scores and higher recovery. The hypertension group, which owned negative average scores showed positive weight gain velocity during the first three months, signaling recovery. Otherwise, the tobacco group, which showed negative average scores, did not possess significant recovery. The findings of this study will assist in developing prevention strategies in the accelerated growth in children exposed to the risk factors. Interventions in early childhood may reflect the health profile and burden of disease during the course of life of these children.

Introdução: Estudos vêm demonstrando que o ambiente intrauterino influencia no crescimento fetal e extrauterino, repercutindo no perfil de saúde em longo prazo. Objetivo: Comparar a velocidade de crescimento durante os primeiros três meses de vida de crianças geradas em ambientes intrauterinos considerados adversos. Métodos: Trata-se de um estudo longitudinal prospectivo controlado desenvolvido com pares de mãe-filho residentes em Porto Alegre/RS. Cinco grupos de exposição foram estudados (diabetes, hipertensão arterial, tabaco e restrição do crescimento intrauterino) e um controle. O crescimento foi avaliado em cinco momentos (pós-parto, sete dias, quinze dias, um mês e três meses) utilizando os índices peso para idade (P/I), comprimento para idade (E/I) e Índice de Massa Corpórea para idade (IMC/I). A análise de regressão Equações de Estimativas Generalizadas foi utilizada para avaliar a relação entre o ambiente intrauterino e o crescimento. A velocidade de crescimento foi avaliada com um e três meses, utilizando a diferença entre as medidas de escore z (delta). Identificou-se a influência de fatores sociodemográficos, maternos e neonatais no peso ao nascer e na velocidade de crescimento. Resultados: Os fatores que influenciaram no peso ao nascer foram: paridade, IMC pré-gestacional, ganho de peso durante a gestação, tipo de parto e sexo. Ao utilizar o escore z de P/I, verificou-se que os grupos tabaco e restrito apresentaram médias significativamente menores do que o controle. De zero a um mês, a velocidade de ganho de peso entre os restritos foi significativamente maior do que os demais. De zero a três meses, só não foi significativamente maior do que o grupo hipertensão arterial. A velocidade de ganho de comprimento de zero a um e de zero a três meses foi significativamente maior no grupo restrito ao comparar com o controle. Ao utilizar o escore z de IMC/I, os grupos tabaco e restrito apresentaram médias significativamente menores do que o grupo controle. A velocidade de ganho de IMC de zero a um mês do grupo restrito só não foi significativamente maior do que o grupo hipertensão arterial. De zero a três meses, foi significativamente maior do que todos os demais. Os fatores que influenciaram na velocidade de crescimento foram: situação conjugal, IMC pré-gestacional, ganho de peso durante a gestação e internação hospitalar da criança. Conclusão: O presente estudo identificou que a velocidade de crescimento nos três primeiros meses de vida é influenciada por ambientes intrauterinos adversos e diferentes fatores gestacionais e neonatais estão envolvidos neste contexto. O grupo restrito foi o que apresentou os escores médios mais baixos e a maior recuperação. O grupo hipertensão arterial, que possuiu escores médios negativos, apresentou velocidade de ganho de peso positiva durante os primeiros três meses, sinalizando recuperação. Já o grupo tabaco, que apresentou escores médios negativos, não possuiu recuperação significativa. Os achados deste estudo poderão auxiliar na elaboração de estratégias de prevenção do crescimento acelerado em crianças expostas a fatores considerados de risco. Intervenções realizadas na infância inicial poderão refletir no perfil de saúde e na carga de doenças durante o curso da vida destas crianças. / Introduction: Studies has demonstrated that the intrauterine environment influences on fetal and extrauterine growth, reflecting the long-term health profile. Objective: To compare the growth velocity during the first three months of life among children born in intrauterine environments considered adverse. Methods: It is a prospective controlled longitudinal study developed with mother-infant pairs living in Porto Alegre/RS. Four exposure groups were studied (diabetes, hypertension, smoking and intrauterine growth restricted) and a control. Growth was evaluated in five moments (postpartum, seven days, fifteen days, one month and three months) using the weight for age (W/A), height for age (H/A) and Body Mass Index for age (BMI/A). Regression analysis with generalized estimating equations were used to evaluate the relationship between the intrauterine environment and growth. The growth velocity was performed with one and three months using the difference between the z-score measures (delta). Were identified the influence of sociodemographic factors on maternal and neonatal birth weight and growth velocity. Results: Factors that influence the birth weight were: parity, pre-pregnancy BMI, weight gain during pregnancy, type of delivery and sex. By using the z score for W/A, it was found that tobacco and intrauterine growth restricted groups had significantly lower average than the control. From zero to one month, the weight gain velocity between intrauterine growth restricted was significantly higher than the others. From zero to three months, weight gain velocity of the intrauterine growth restricted group was significantly higher than the other groups, except hypertension. The length gain velocity from zero to one and three months was significantly higher in the intrauterine growth restricted vs. control. By using the BMI/A z score, tobacco and intrauterine growth restricted groups had significantly lower average than the control group. From zero to one month, only BMI gain speed intrauterine growth restricted group was not significantly higher than the hypertension group. From zero to three months, was significantly higher than the others. The factors that influenced the growth velocity were: marital status, pre-pregnancy BMI, weight gain during pregnancy and the child's hospitalization. Conclusion: The present study identified that the growth velocity in the first three months of life is influenced by adverse intrauterine environment and different gestational and neonatal factors are involved in this context. The intrauterine growth restricted group was the one with the lowest average scores and higher recovery. The hypertension group, which owned negative average scores showed positive weight gain velocity during the first three months, signaling recovery. Otherwise, the tobacco group, which showed negative average scores, did not possess significant recovery. The findings of this study will assist in developing prevention strategies in the accelerated growth in children exposed to the risk factors. Interventions in early childhood may reflect the health profile and burden of disease during the course of life of these children.

Berberine is an isoquinoline alkaloid found in some plants and has many bioactivities including anti-microbial, lipid- and glucose-lowering, anti-cancer, anti-inflammatory, etc. However, there is limited knowledge about berberine’s effects on development and locomotive activity. Herein, in vivo studies were conducted to determine these effects of berberine using Caenorhabditis elegans as an in vivo model. Treatment of berberine at 50 μM starting at L1 stage significantly retarded the growth rate of nematodes, and reduced the length, width and moving speed of worms by 19%, 12% and 29%, respectively, compared to the control. In addition, triglycerides (TG) and protein content in worms was reduced by 23% and 28%, respectively, after berberine treatment from L1 stage compared with the control group. However, no significance was observed when berberine was treated from young adult stage. These findings suggest that berberine has effects on development in C. elegans.

The effect of maternal dietary fats on growth rate and bone development of commercial broilers was examined. Three hundred fifty female chicks were winged banded, weighed and equally divided among six starter pens (1.52 X 3.66m) with litter floors. At 20 wk of age, each pen was fed a basal laying diet supplemented with either 3% chicken fat (CF), soybean oil (SBO) or menhaden oil (MO). Each diet was provided with or without the antioxidant ethoxyquin, producing a total of six dietary treatments. Addition of fats [soybean (SBO), menhaden oil (MO), chicken fat (CF), soybean + antioxidant (SA), menhaden + antioxidant (MA), and chicken + antioxidant (CA)] to the maternal diet altered the tissue and yolk composition of hens to reflect the dietary source. Response variables measured were body weight, tibia weight and length, and breaking strength (stress, force, energy, bone wall, and diameter). Chick tissue from hens fed a MO and MA diet exhibited greater (P<0.01) amounts of DPA (22:5n3), DHA (22:6n3) and total n-3 fatty acids than the remaining dietary treatments. Tissues from chicks fed a SBO and SA diet displayed larger levels of 18:2n6 and total n-6 fatty acids when compared to all other treatments. Male and female chicks from the menhaden type diets (MO and MA) were lighter (P<0.01) during grow out period than from soybean (SBO and SA) and chicken (CF and CA) type diets. Chicks tibiae diameter from CF maternal diet tended to be larger than the MO maternal diet, with significance being noted at d 14 (P<0.01) and 28 (P<0.01). Increases were observed in shear force and stress required to break chick tibia from SBO maternal diet compared to those from the CF and MO maternal diets. The SBO maternal diet stimulates growth rate and bone development and strength of the progeny. (Key words: chickens, bone development, breaking strength, growth rate, fatty acids) / Master of Science

The subsumed work of this dissertation is comprised of three independent but interrelated studies which seek to further the understanding of processes which govern the coprecipitation of trace elements with calcite and aragonite minerals. These studies investigate the effects of: 1) pressure on crystal morphology and trace element incorporation to aragonite; 2) growth rate on uranium partitioning between calcite and fluid; 3) aqueous Mg/Ca on the magnesium partitioning to low-magnesium calcite. The importance of this work is to determine how the environment of formation and growth rate influences the geochemistry of CaCO3 in order to improve existing paleoproxies and develop new ones. In the first study a series of experiments were conducted at 1, 25, 75, 100, and 345 bars of nitrogen – this range covers pressures at the oceanic floor. Aragonite precipitation was induced by the one-time addition of a Na2CO3 solution to an artificial seawater. Results suggest that oceanic floor pressures could affect the crystallization of CaCO3 by altering mineralogical composition and aragonite crystal size. In the second study calcite crystallized from NH4Cl-CaCl2-U solution by diffusion of CO2. The calcite growth rate was monitored by sequential spiking of the calcite-precipitating fluids with REE dopants. The resulting crystals were analyzed using Secondary Ion Mass Spectrometry (SIMS). Results showed that the partitioning of uranium increases with increasing growth rate. Growth entrapment model (GEM) and unified uptake kinetics model (UUKM) explain the obtained data.In the third study CaCO3 precipitated in NaCl solution by continuous addition of CaCl2, MgCl2, and either Na2CO3 or NaHCO3. The Mg/Ca of the fluid was adjusted in an attempt to produce calcite where Mg/Ca would match Mg/Ca in foraminifera shells. It was observed that multiple CaCO3 polymorphs precipitated from fluids at high pH (Na2CO3 doping experiments). This result underscores the potential control of pH and/or supersaturation state on CaCO3 polymorph precipitated from low Mg/Ca solutions. Calcite was the only mineral crystallized at low pH (NaHCO3 doping experiments). It was determined that Mg partition coefficient between calcite and fluid (KMg) negatively correlates with Mg/Ca(Fluid) when it exceeds 0.5 mol/mol; no systematic correlation was observed when 0.05< Mg/Ca(Fluid)<0.5 mol/mol.