VictorJuiz/thesis huggingface dataset:
Growth and nutrient dynamics of nutrient-loaded black spruce seedlings in relation to neighbouring vegetation on boreal mixedwood sites

Early growth. and nutrient dynamics of newly planted, nutrient-loaded black spruce (Picea mariana W.) B.S.P.) seedlings and natural vegetation was investigated in a series of greenhouse and field experiments conducted on three boreal mixedwood sites to assess nutrient storage and utilization processes in plants. Nutrient-loaded seedlings were similar in height and biomass to nonloaded seedlings at planting, but contained 43-106, 76-134, and 33-102% more tissue N, P, and K content respectively, due to higher nursery fertilization, which induced luxury consumption. After transplanting, however, loading improved seedling growth in herbicide-treated and untreated plots, resulting in growth reduction in natural vegetation. Above-ground biomasses of seedling and natural vegetation were negatively correlated indicating that increase in crop biomass was at the cost of weed biomass, and vice-versa. Loading response in seedlings was attributed to earlier and greater biomass and nutrient partitioning to current needles and roots, that promoted seasonal N uptake (21-212 %) and reduced soil N availability by 6-20%, suggesting greater preemption of below-ground nutrient resources. The enhanced competitive ability of loaded seedlings over naturally occurring vegetation was probably due to the contrasting nutrient utilization traits induced by greenhouse fertilization. The lower fertility regimes of nonloaded seedlings preconditioned the plants to conserve nutrient reserves once outplanted, allowing moderate new growth development, but ensuring adequate internal nutrient supplies for future growth. Higher fertility regimes from loading practices, in contrast, conditioned an exploitive strategy in the plants, which took advantage of internal nutrient reserves for rapid initial growth and early establishment at the expense of accumulated reserves. While both loading and herbicide treatments stimulated seedling growth and N uptake, N retranslocation from older to actively growing tissues was promoted by loading but reduced by herbicide treatment. The results demonstrate the high dependence of seedlings on internal nutrient reserves when planted in competitive environments, and that nutrient retranslocation processes are mainly driven by current growth, nutrient uptake, and internal nutrient reserves. Data from these experiments and from the literature are integrated in a conceptual model that links internal nutrient cycling processes to seedling growth under interspecific competition.
An empirical assessment of Canadian highway traffic laws

The objective of this thesis is to assess empirically the effects of Canadian highway traffic legislation enacted between 1975 to 1992. The chosen period represents an interesting phase in the evolution of Canadian traffic laws as it was characterized by the enactment of initiatives aimed at safer driving, such as mandatory seatbelt legislation and stricter impaired driving laws. These laws may have had the desired effects as both total and legally intoxicated (impaired) driver death rates fell by nearly 50% over the same time period. This study attempts to evaluate whether this decline in driver fatalities is correlated with the enactment of stricter highway traffic laws. However, vehicle safety initiatives such as mandatory seatbelt laws may also result in higher pedestrian deaths. This is because such initiatives often give drivers an increased sense of security, encouraging them to take risks. The benefits of vehicle safety legislation may, therefore, be offset by rising pedestrian deaths. This is the premise of Peltzman's offset hypothesis. I test for offsetting behavior by estimating the impact of mandatory seatbelt laws on pedestrian fatality rates. This research offers the following conclusions. First, the impact of impaired driving laws seems to be a function of the blood alcohol content (BAC) level of individual drivers as stricter penalties are weakly correlated with legally intoxicated drivers, but have a stronger effect on driver fatalities with BAC levels just below or above the permissible limit. On the other hand, mandatory seatbelt laws are correlated with a 16% to 18% fall in impaired driver deaths, suggesting that resources allocated towards deterring drinking and driving would have a greater impact if devoted towards improving the safety features of vehicles. Finally, there seems to be little evidence of offsetting behavior as seatbelt laws have an insignificant effect on pedestrian fatalities.
High-voltage RF silicon bipolar transistor

Conventional RF silicon bipolar transistors have a major limitation for analog applications due to their low breakdown voltage. The objective of this thesis is to propose a new bipolar transistor structure with improved breakdown voltage without sacrificing the frequency performance. A novel guarded emitter device with an extra p+ diffusion included in the active area is suggested for this purpose. In this structure, the additional p+ region modifies the shape of the base-collector depletion region and results in an increase in collector to emitter breakdown voltage (BVCEO) by preventing the premature punchthrough of the base region. Other advantages include: a higher emitter perimeter to base area ratio achieved with this type of configuration resulting in better frequency performance and the reduction of the overall device area (25%). The process used in the implementation of the device is a 0.8 [mu]m BiCMOS compatible process which utilizes a thin (900Å) SEG (S_elective E_pitaxial G_rowth) base layer, shallow emitters formed by in-situ phosphorus doped polysilicon emitter technology and self-aligned extrinsic p+ base regions. Design considerations related to the process flow, two-dimensional process and device simulations are presented. The fabricated test structures were electrically characterized (DC and RF measurements). Specific results include a 12 V collector-emitter breakdown (BVCEO) and a 8.8 GHz cutoff frequency for a 0.8 [mu]m guarded emitter transistor as compared to a breakdown voltage of 2 V and a cutoff frequency of 6.8 GHz for the conventional device operated under identical device operated under identical conditions.
A narrative inquiry into home, a space called anywhere

The theory explicated in Home: A Space Called Anywhere was born in the experience of leaving home after 25 years. The focus is the universal yet particular concept of home, the sentiment of 'at home', and its function in how the world is viewed and understood. The phenomenon of changing geographic and personal space is examined within personal, social and educational contexts of spaces we call home to discover how behaviour is determined and knowledge created in a world of change and uncertainty. On a continuum of a physical move at one end and a mental move at the other, a dialectical notion of experience exists. Changing space, and separation, exposed the complexities of adaptation and harmony. The traditional concept of home was no longer a fixed permanent space and the sentiment of 'at home' was freed of any fixed location. The resolution of an image of home is critical in understanding the sense of belonging that this emotion evokes. This study is the narratives of three families and settings of home. Multiple issues surfaced guiding the inquiry into narrative, folkloric methodologies. The data was composed of interviews and participation in the activities of my participants. An eclectic collection of documents such as journals, death and birth certificates, historical texts, recipes and perusal of artifacts presented an historical and cultural profile of familial and personal lifestyles. My participants are elderly, deeply rooted, and have a vast reservoir of practical knowledge. The intimacy of story revealed the sentiments that shaded and built memories. The hermeneutical quality of story rendered the multiple perspectives of cultural realities. Tradition implies preservation and permanence. Inclusion of photographs complements the text, adding permanence to moments. The universality and familiarity of home can be a benefit and detriment in the context of schooling and educational research. Images of school as home can establish a sense of interdependence and community. Other images suggest an absence of harmony, a separation of space and sentiment. A generational and conceptual gap establishes an ironic relationship between today's society and the past, between my elderly participants and students in today's schools. Leaving home is an educative experience one can presume many encounter; a life experience about adaptation and for some painful.
The role of hyaluronan receptor RHAMM in breast carcinoma

Hyaluronan (Hyaluronic acid, hyaluronate, HA), a ubiquitous extracellular matrix molecule, has been implicated in the process of cell motility and tumor progression. Its receptor RHAMM is critical for the locomotion and growth of tumor cells. RHAMM is an oncogene that regulates signaling through ras and controls MAP kinase (ERK) in murine fibroblasts. The purpose of this study is to understand whether RHAMM is involved in human breast cancer progression. It was found that HA production was correlated with the rate of invasiveness of human breast cancer cell lines 'in vitro' and most strongly predicted the ability of these cells to invade and metastasize in nude mice. Addition of 1 mg/ml of HA stimulated invasion of previously non-invasive cell lines that made little endogenous HA and further enhanced invasion of invasive cell lines. RHAMM was also shown to be involved in the motility and invasion in these cell lines 'in vitro' as indicated by peptide and antibody blocking studies. RHAMM occurred as at least two isoforms in breast cancer cells although the function of each isoform was not investigated. In breast cancer patients, overexpression of RHAMM in subsets of tumor cells within the primary tumors of two patient cohorts was significantly prognostic of poor outcome and enhanced the prognostic value of lymph node status. Metastatic cells within lymph nodes exhibited a significantly higher level of RHAMM expression than the primary tumors. Further, RHAMM expression was significantly correlated with overexpression of both ras and ERK in primary tumors. Although the increased levels of RHAMM expression in breast cancer cell lines cloned from several separate tumors against a heterogeneous background 'in vitro' did not correlate with either motility or invasion rate, or indeed with the presence of ras mutations, in the MCF-10A background cells lacking other mutations, however, the presence of an active mutant ras enhanced RHAMM expression. Therefore, these results indicate that RHAMM is commonly involved in the locomotion and invasion of human breast cancer cells, consistent with its ability to predict poor prognosis of breast cancer patients. RHAMM is therefore a cell motility regulator.
Ultra-fast automatic placement for FPGAs

As Field-Programmable Gate Array (FPGA) device capacities have grown, the computation time devoted to placement and routing of circuits has grown more dramatically than the available computer power. Thus, high-speed FPGA compilation tools are critical. This thesis presents an ultra-fast placement algorithm for FPGAs. It is based on a combination of multiple-level, bottom-up clustering and simulated annealing. It provides superior area results over a known high-quality placement tool on a set of large benchmark circuits, when both are restricted to short run times. It can generate a placement for a 100,000-gate circuit in 10 seconds on a 300 MHz Sun UltraSPARC. The high-quality tool, using a pure simulated annealing algorithm, generates a placement that is 24% better than our tool, but takes 524 seconds; it needs 50 seconds to achieve the same placement quality as our tool. Furthermore, when operating in its fastest mode, our tool can provide an accurate estimate of the wirelength achievable with good quality placement. This can be used, in conjunction with a routing predictor, to very quickly determine the routability of a circuit on a given FPGA device.
A study of the flow through ultraviolet disinfection systems

In this work, the hydraulic characteristics of an ultraviolet wastewater disinfection unit were studied. A commercially available system manufactured by Elsag Bailey (Canada) Inc. was placed in an open channel flume. Measurements were made over a range of channel velocities from 20 to 60 cm/s. Dye was injected into the flow and videotaped in order to provide both a qualitative and quantitative analysis of the mixing occurring within the disinfection unit. Velocity measurements were conducted along the length of the unit using an Acoustic Doppler Velocimeter and from this data the overall turbulence intensity within the unit was estimated. The design of the unit was altered by reshaping the upstream ends of the unit and by installing washers along the length of the quartz sleeves. It was found that the addition of washers significantly increased the mixing throughout the unit and is expected to improve considerably the disinfection efficiency of the wastewater system. Microbiological tests are being conducted currently by Elsag Bailey to quantify this increase in efficiency.
Reconstructing bankruptcy law in Canada, 1867 to 1919, from an evil to a commercial necessity

In the nineteenth century, Canadian bankruptcy legislation was not widely accepted as a means to distribute assets to creditors or as a way to provide a debtor with a fresh start. In 1880, Parliament repealed the 'Insolvent Act of 1875' and abandoned its constitutional jurisdiction over bankruptcy and insolvency until 1919. Much of the debate in the nineteenth century focused on the morality of the discharge and whether it interfered with a debtor's higher obligation to repay debts. Notions of forgiveness competed unsuccessfully with the idea that all debts had to be honoured. The collective nature of bankruptcy proceedings and the distribution of the debtor's assets on an equal basis were also central to the debate. Bankruptcy law's interference with the traditional common law scramble for the debtor's assets affected the specific interests of local and distant creditors. Bankruptcy law represented, therefore, both a conflict of values over the morality of the discharge and a distinct divergence of interests between local and distant creditors over the advantages and disadvantages of a pro rata distribution. This clash of ideas and interests took place within a changing economy that was moving away from its local and rural base. Repeal in 1880 was symbolic of the weakness of the national economy. By 1919, uniform bankruptcy legislation could no longer be delayed in an expanding national market. Credit relationships became less dependent upon matters of character and the bankruptcy discharge became more acceptable as a central feature of the legislation. Institutional factors such as federalism and the emerging regulatory state also had an independent effect on the legislative history. In the 1870s, the absence of a strong government department and bureaucracy inhibited the implementation of stable and lasting legislation. In 1919, bankruptcy reform coincided with an unprecedented growth of federal regulation during the War. Federalism also affected the timing of the legislation. The ability of the provinces to regulate voluntary assignments and the administration of debtors' estates alleviated the immediate need for federal legislation until after the turn of the century.
Simulation [of] the tube drawing process using the finite element method

The power law and the Ramberg-Osgood constitutive equations are commonly used for describing material behavior. The Ramberg-Osgood equation is the more popular one as it is capable of describing behavior of several materials over the entire range of deformation. Previous research revealed, however, that the Ramberg-Osgood equation is not capable of describing the behavior of materials which exhibit sudden changes. One of the goals of this research was to develop a more accurate and efficient way of describing materials behavior. This goal has been achieved as a new equation, called the Alpha constitutive equation, has been developed. This equation is very accurate and efficient as well due to the ability of one equation being able to describe the behavior of any material--even materials that exhibit strain softening. The second phase of this research focused on developing a finite element program to simulate the tube drawing process which involves large plastic deformation and complicated boundary conditions. A specialized code to simulate the tube drawing in the presence of a mandrel has been developed. This finite element program has the ability to accept materials data in the form of a modified Ramberg-Osgood equation as well as the Alpha equation. A special technique was devised and implemented in the finite element program to avoid instability that tends to occur at the die exit. The finite element simulation results achieved in terms of the prediction of the drawing force compares well with the results obtained by Ontario Hydro Technologies. In addition, experiments conducted at Ontario Hydro revealed the formation of shear cracks on the outer surface of the tube. The finite element simulation results are consistent with this observation as the results indicate that maximum shear stress does exist at the outer walls of the tube which is responsible for the formation of shear cracks. The FEM program developed has the added advantage of having the capability to determine the stresses under unsteady state (transient) conditions. In addition, the residual stresses in the material can be determined. This research work is far from over--it is only the beginning of a very promising step to reach the goal of being able to use mathematically simulations to accurately simulate tube forming processes.
The effects of irrelevant information and stimulus uncertainty on the aging visual memory system

Previous research has shown that old observers' behavioral performance on basic spatial frequency memory tasks is comparable to that of young observers. PET research suggests that old observers' preserved behavioral performance may depend on the operation of neural compensatory mechanisms. Presumably, when task difficulty increases, there exists a limit beyond which the elderly brain can no longer compensate. The current study examined whether or not adding irrelevant information and stimulus uncertainty would exceed the capacity of the elderly brain's compensatory mechanisms. We found no age effects for observers aged 60 to 69, and significant age effects for observers aged 70 and above. We conclude if neural compensatory mechanisms subserve the ability to perform like young observers, then these mechanisms continue to work even when irrelevant information and stimulus uncertainty is added to the task for observers aged 60-69, but not for observers aged 70 and above.
The ceramic correlates of decline in the Mamluk Sultanate, an analysis of late medieval sgraffito wares

The term "sgraffito" refers to a ceramic decorative technique in which a design is cut through a light-colored slip to reveal the dark-colored earthenware body of the vessel's fabric. Sgraffito ware was one of the most common and widespread forms of regular tableware in Islam and Byzantium from roughly the twelfth century until the fifteenth. Egyptian sgraffito as a barometer of social decline in the Mamluk Sultanate is the focus of the following study. Each of the seven chapters of this study addresses different problems associated with Egyptian Mamluk sgraffito and relates them to the larger question of the ceramic correlates of social decline in militarized societies. Chapter One defines the characteristics of Mamluk sgraffito and the problems inherent in its analysis and interpretation. Chapter Two reviews the on-going scholarly debate about the decline of the Mamluk Sultanate and suggests ways in which ceramic analysis can contribute to this debate. Chapters Three through Six document developments in sgraffito with reference to "decline" in military societies. The survey of the history of medieval sgraffito ware which comprises Chapter Three situates Mamluk sgraffito in a long tradition of ceramic development from sgraffito's origins in tenth-eleventh century Persia. The Egyptian ware is defined as a local Zeuxippus-derivative which continued to mature under the influence of imports of Cypriot sgraffito into the early fourteenth century. Chapter Four defines the Cypriot sgraffito style and relates its development in the thirteenth and fourteenth centuries to the gradual militarization and subsequent weakening of Lusignan society. Egyptian Mamluk sgraffito is analyzed in Chapters Five and Six, which formulate a typology and rough chronology of the ware and investigate its social meaning in official ceremonial, respectively. It is suggested that the genesis of the "military style" was related to the rise of the amiral class at the turn of the fourteenth century and that its subsequent development was a response to the social effects of particular policies initiated by al-Nasir Muhammad during his third reign. The thesis concludes in Chapter Seven with an evaluation of the potential of ceramics for documenting aspects of social decline in medieval societies.
Porous tin(IV) sulfide materials

Synthetic routes were developed which yield large single crystals and phase pure R-SnS-1 and R-SnS-3 materials. SCXRD and PXRD structure analysis revealed that they have nanoporous layered structure with an unique framework flexibility. To accommodate the change of template cations, guest molecules and applied pressure, they undergo elastic deformations to change the unit cell symmetry, the shape/size of pores within the tin sulfide layer, the relative registry of the tin sulfide sheets and the interlamellar distance. Depending on the guest molecules, gas adsorption by these materials can be a pure micropore-filling process or a combination of micropore-filling and intercalation. The selective, fast and large electrical response of these SnS-n materials to certain types of guest molecules make them attractive candidates as chemical sensing elements. The formation pathway of the SnS-n materials was examined and the function of templates, mineralizers, pH and temperature profiles were studied. It was demonstrated for the first time that the SnS-1 material can be formed at room temperature from the assembly of dimeric [Sn2S6] 4- species in an aqueous solution. The framework integrity of both SnS-l and SnS-3 can be maintained up to 200-250°C. Above this range, the occluded organic cations and chemisorbed water molecules react with the tin sulfide framework, and transform it to dense packed SnS 2. Sn2S3. SnS and SnO2. The local bonding properties of these materials were investigated by solid state 119 Sn CP-MAS NMR, Mössbauer and Raman spectroscopes; and the optical and electronic properties characterized by single crystal optical absorption and luminescence spectroscopes. A novel thermotropic tin sulfide semiconductor material, Meso-SnS-1, was synthesized and characterized. It is best described to have a structure based upon porous tin sulfide layers sandwiched by hexadecylamine-bilayers. Meso-SnS-1 undergoes a reversible thermal transition at 80-90°C to form either a Smectic C or Nematic LC phase. The conductivity of Meso-SnS-1 was found to be 5 * 10-8 and 5 * 10 -5 [Omega]-1 at RT and 90°C respectively. A whole family of thermotropic fin sulfide materials is envisaged by varying the long chain amine as well as the structure of the tin sulfide component.