Quantum-Dot Cellular Automata (QCA) is being investigated as a possible alternative for encoding and processing binary information in an attempt to realize dramatic improvements in device density and processing speed over conventional CMOS design. The binary information is encoded in the locations of two excess electrons in a system of four quantum dots. The dots are arranged with each on a corner of a square, and electrons are able to quantum-mechanically tunnel between dots. Each set of four dots and two excess electrons constitutes a QCA cell. Coulomb repulsion ensures that the electrons will tend to occupy antipodal sites, giving two possible polarizations, or lowest energy ground states for a QCA cell. The electrons would tend to align along one diagonal or the other. Arrangements of QCA cells can be used to pass along input binary information and perform necessary logic operations on the input signal.When electrons tunnel back and forth between dots, it is possible they will occupy excited states in the dots. Two undesirable effects result from this: 1) Energy will be dissipated to the environment and cause thermal heating, and 2) it is possible a cell could become locked in a metastable state, which may be a local energy minimum, but is not one of the ground state polarizations we desire. Through the modulation of the heights of the inter-dot potential barriers, it would be possible to allow electrons to more easily tunnel between dots. This would help prevent the system from reaching excited states. The time variance in the heights of the potential barriers must be greater than the time it takes for the electrons to tunnel between dots, thus, effectively clocking the QCA device.We present theoretical studies of controlling the inter-dot potential barriers in a QCA device using an electric field due to electrostatically charged rods. The amount of charge on the rods is varied in time to increase and decrease the electric field, which will raise and lower the inter-dot potential barriers as desired. Different arrangements of rods provide different time-dependent behavior in the electric field, which may be useful depending on the arrangements of QCA cells required to make a logic device. / Department of Physics and Astronomy

The strive to increase the engine efficiency in terms of fuel consumption and lower emissions have lead to higher demands on materials. In this thesis five different thermal barrier coatings applied using air plasma spraying to three materials commonly used for exhaust application are evaluated. This thesis work was done at Scania CV in Södertälje with main focus on evaluation during thermal cycling. The goal of this thesis is to evaluate the coatings and correlate their behaviour to their characteristic microstructure. The coatings were evaluated through their stability in thermal conductivity, fracture toughness, hardness, porosity and failure modes. The parameters where obtained using laser flash, Vickers indentation, Vickers indentation fracture toughness and microscopic evaluation methods. The evaluation shows that conventionally used zirconia based materials exhibits low thermal conductivity, high hardness, and stable fracture toughness compared to other evaluated materials. One material that can be applicable in diesel exhaust application is mullite, which showed similar performance to zirconia based materials. For the use of TBC together with SiMo51 a different bondcoat than conventional NiCrAlY needs to be evaluated. / Strävan efter att konstruera effektivare motorer för att generera minskade utsläpp och bättre bränsleekonomi har genererat högre krav på konstruktionsmaterialen som används idag. I detta examensarbete som utförts på Scania CV i Södertälje utvärderas fem olika termiska barriärsskikt som belagts med plasma sprayning på tre vanligt förekommande konstruktionsmaterial för grenrör. Målet med detta examensarbete är att utvärdera beläggningarnas beteende under termisk cykling och koppla deras beteende till karakteristiska mikrostrukturer. Beläggningarna utvärderades genom att jämföra deras värmeledningsförmåga, hårdhet, brottseghet och porositet. Materialparametrarna utvärderades genom laser flash, Vickers hårdhetsmätning, Vickers brottseghet samt mikroskopiska bildanalyser. Resultaten visar att kommersiellt använda zirkonium baserade material uppvisar låg värmeledningsförmåga, hög hårdhet och hög brottseghet i förhållande till övriga material. Ett annat material som analyserats, mullit, visar på liknande beteenden som zirkonium baserade material men behöver utvärderas ytterligare. Om SiMo51 används som substratmaterial finns behovet att utvärdera användningen av andra typer av bindskikt än det austenitiska NiCrAlY nu använt.

The goal of this creative project was to design an The objectives of the study were to determine:(1) how other professions become sensitive to the needs of the handicapped (2) the state-of-the-art in landscape architecture profession as related to design for the handicapped (3) the degree to which issues concerning the needs of the handicapped are architecture curriculums.The literature review section of this project focused on the social and emotional needs of the handicapped along with the physical design criteria used by the landscape architect. The literature review section also identified the different teaching strategies that are most effective in sensitizing landscape architecture students to needs of the handicapped. / Department of Landscape Architecture

No description available.

The purpose of the study was to measure and analyze the accessibility of facilities housing programs in Architecture in the North-East and East-Central Regions of the Association of Collegiate Schools of Architecture.The philosophical basis for the study was a theory in Architecture that the environment can teach. Extending the theory to the topic of the study, students of Architecture needed to learn in buildings accessible to the disabled in order to have the best chance of designing accessible buildings in professional practice.The thirty-three sites included in the study were visited between August and November of 1980, after the buildings were required by law to be accessible. The Revised Accessibility Checklist recommended by the Iowa Chapter of the American Institute of Architects was used to gather the data The Accessibility Checklist was based directly on the requirements of Specification 117.1 of the American National Standards Institute. Section 504 of the Rehabilitation Act of 1973 required all facilities to meet the standards established in ANSI Specification 117.1. Data were also gathered regarding design characteristics, including age, style of design, original use, extent of renovation, and context of location, to determine whether accessibility was influenced by specific design factors. Criteria were established in the dissertation to determine whether a building was excellent, good, average, below average, or poor in accessibility to disabled persons.Of the facilities surveyed, three were excellent, three good, three average, twelve below average, and eleven poor in terms of accessibility to disabled persons. Overall, the buildings rated below average. Twenty-three of the thirty-three buildings surveyed, seventy percent, did not comply with Federal accessibility law. Thirty-six percent of the buildings did not have an accessible primary entrance; fifty-two percent of the rest rooms were not accessible; and thirty-two percent of the buildings did not have elevators.Major conclusions regarding design characteristics were: 1) The design characteristic with the greatest influence on accessibility was extent of renovation. 2) Modern buildings rated better than revival structures. 3) Buildings completed since 1960 received higher accessibility classifications than buildings completed earlier. 4) Buildings located in a campus setting received higher classifications than urban structures.Recommendations for specific renovations to the thirty-three facilities surveyed were made for improving accessibility. The study also recommended the American Institute of Architects, the Association of Collegiate Schools of Architecture, and member schools should establish a policy of making teaching facilities accessible to the disabled.

The blood-brain barrier (BBB) formed by the brain capillary endothelial cells provides a protective barrier between the systemic blood and the extracellular environment of the central nervous system. Since most fatty acids in the brain enter from the blood, we examined the mechanism of permeability of various fatty acids across primary human brain microvessel endothelial cells (HBMEC). Cardiolipin (CL), a major mitochondrial phospholipid involved in energy metabolism in mammalian mitochondria, and fatty acid transport protein-1 (FATP-1) may regulate the intracellular level of fatty acyl-Coenzyme A’s. Since fatty acids are required for oxidative phosphorylation via mitochondrial oxidation, we also examined the effect of altering FATP-1 levels on CL biosynthesis. The permeability of radiolabeled fatty acids was determined using confluent cells grown on Transwell® inserts following inhibition of various fatty acid transporters. The passage of [1-14C]oleate across confluent HBMEC monolayers was significantly enhanced when fatty acid free albumin was present in the basolateral media. Knockdown of FATP-1, FATP-4, fatty acid translocase/CD36, or fatty acid binding protein 5 significantly decreased permeability of a number of radiolabeled fatty acids across the HBMEC monolayer from either apical as well as basolateral sides. The findings indicate that transport of some fatty acids across HBMEC is, in part, a transcellular process mediated by fatty acid transport proteins. Next, HEK 293 cells were used as a model to determine the effect of altering FATP-1 levels on CL. HEK-293 mock- and FATP-1 siRNA-transfected cells or mock and FATP-1 expressing cells were incubated for 24 h with 0.1 mM oleate bound to albumin (1:1 molar ratio) then incubated for 24 h with 0.1 mM [1,3-3H]glycerol and radioactivity incorporated into CL determined. FATP-1 siRNA-transfected cells exhibited reduced FATP-1 mRNA and increased incorporation of [1,3-3H]glycerol into CL (2-fold, p<0.05) compared to controls indicating elevation in de novo CL biosynthesis. In contrast, expression of FATP-1 resulted a reduction in incorporation of [1,3-3H]glycerol into CL (65%, p<0.05) indicating reduced CL synthesis. In addition, in vitro cytidine-5’-diphosphate-1,2-diacyl-sn-glycerol synthetase (CDS) activity was reduced by exogenous addition of oleoyl-Coenzyme A. The data indicate that CL de novo biosynthesis may be regulated by FATP-1 through CDS-2 expression in HEK 293 cells.

The blood brain barrier (BBB), formed by endothelial cells lining the lumen of the brain capillaries, is a restrictively permeable interface that only allows transport of specific compounds into the brain. Cardiolipin (CL) is a mitochondrial- specific phospholipid known to be required for the activity and integrity of the respiratory chain. The current study examined the role of cardiolipin in maintaining an optimal mitochondrial function that may be necessary to support the barrier properties of the brain microvessel endothelial cells (BMECs). Endothelial cells have been suggested to obtain most of their energy through an-aerobic glycolysis based on studies of cells that were obtained from the peripheral vasculatures. However, here, we showed that the adult human brain capillary endothelial cell line (hCMEC/D3) appeared to produce ~60% of their basal ATP requirement through mitochondrial oxidative phosphorylation. In addition, RNAi mediated knockdown of the CL biosynthetic enzyme cardiolipin synthase (CLS), although did not grossly affect the mitochondrial coupling efficiency of the hCMEC/D3 cells, did seem to reduce their ability to increase their mitochondrial function under conditions of increased demand. Furthermore, the knockdown appeared to have acted as a metabolic switch causing the hCMEC/D3 cells to become more dependent on glycolysis. These cells also showed increase in [3H]-2-deoxyglucose uptake under a low glucose availability condition, which might have served as a mechanism to compensate for their reduced energy production efficiency. Interestingly, the increase in glucose uptake appeared correlated to an increase in [3H]-2-deoxyglucose glucose transport across the knockdown confluent hCMEC/D3 monolayers grown on Transwell® plates, which was used in our study as an in vitro model for the human BBB. This suggests that changes in the brain endothelial energy status may play a role in regulating glucose transport across the BBB. These observations, perhaps, also explain why the brain capillary endothelial cells were previously observed to possess higher mitochondrial content than those coming from non-BBB regions (Oldendorf et al. 1977).

This thesis examines the means by which emergency egress for people with a disability can be provided and presents a model for the adoption of egress provisions for persons with a disability into the Building Code of Australia. / With the introduction of the commonwealth Disability Discrimination Act 1992 in March 1993, it became unlawful for a person to be discriminated against based on their disability. In the built environment this meant that all building and facilities are required to be accessible. However, this also includes the right for building occupants to also be safe and not be exposed to any form of adverse conditions such as fire, in a building. / The research undertaken to formulate this model traces the origins of disability rights both internationally and in Australia as well as Australian building code requirements. The technical provisions considered for inclusion in the Building Code of Australia (BCA) have been derived from an international survey of the research that has been undertaken and the various approaches taken by the building codes of other countries. In addition, to consider the appropriateness of the suggested model, a survey was carried out to gauge community expectations. The findings of this survey were then built into the model. / The conclusions show that people are willing to use whatever means of egress is provided if they have the confidence that the exit system will be safe during an emergency. / The research concludes that the technology exists to enable emergency egress for persons with a disability to be provided and that it is possible for the BCA to include specific provisions. / However, it also recognised that for it to succeed, a fully integrated approach addressing human behavioural and management aspects as well as the physical attributes of a building would be required. The present BCA does not take a wholistic view in this regard as it only addresses the physical construction of a building and hence its scope would need to be expanded. / To achieve this overall 'package', it is necessary for a major education campaign by which the community is educated about the use of the egress systems for persons with a disability using both 'protect-in-place' and 'everybody-out' strategies. This is especially the case for the use of lifts as the community has been educated for many years that it is not safe to use lifts in a fire. This requires a shift in the way people think about the use of lifts in a fire and is by far the most challenging component. / Thesis (MBuilding)--University of South Australia, 2003.

Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 1984. / Some mounted ill. Includes bibliographical references (leaves 147-194).

Dissertation (Ph.D.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.