5,226 research outputs found

    Katie’s Closet: An On-campus Experiential Learning Project

    Get PDF
    Two faculty and one undergraduate student embarked on an applied learning experience to determine the feasibility of starting a free professional clothing shop for University students called Katie\u27s Closet. All aspects of conceptualizing and testing the Katie\u27s Closet pop-up-store concept began from a feasibility study. With the support of faculty mentors, the undergraduate student researched, analyzed, and executed the project. The action research project started with informational interviews and a focus group for gathering qualitative data on the student population\u27s needs. These findings led to more research to explore potential collaborative partnerships with other University departments. Competitive benchmarking also supported developing the entrepreneurial project concept and offered insightful information to help with the start-up. The data provided the foundational knowledge to create and market a Katie\u27s Closet pop-up store on campus. This article is a collaborative effort written by both the undergraduate student intern and her faculty mentors

    Rapid reserve generation from a Francis Turbine for system frequency control

    Get PDF
    The increase in contributions from non base load renewables, such as wind and solar,can have adverse effects on the stability of an electrical grid. In this study, the possibility of rapidlyloading a Francis turbine from a tail water depression (TWD) mode for providing additional systemfrequency control is investigated. Based on the analysis of full-scale TWD test results and keyfindings from the transient testing of a micro-hydro scale turbine unit, a detailed description ofthe TWD transition process is given. The formulation of an improved turbine model for use inone-dimensional hydro-electric plant models is presented with simulation results compared tofull-scale data. The analytical model, which calculates output power according to the conservation ofangular momentum and identified sources of loss, is used in parallel with full-scale and model scaletest observations to elucidate the events and mechanisms occurring during this proposed transition.The output response, in terms of active power, was found to be highly dependent on guide vaneopening rate in both full-scale and model tests. For an approximate doubling in opening rate, theduration of the reverse power flow was reduced by 38% and 21%, for full-scale and model units,while the low pressure transient increased by 16% and 8%, respectively. The analytical model wasshown to capture the general response characteristic in all cases tested; however, output powerresponse was over predicted due to two identified model assumptions made, while, for the morerapid opening, the penstock pressure was under predicted by approximately 15%

    Interventional cardiology : Cost-effectiveness of PCI guided by fractional flow reserve

    Get PDF
    Coronary revascularization strategies have been evaluated in numerous clinical trials. As coronary revascularization has become more common, concerns over financial costs have increased

    Retrospective harm benefit analysis of pre-clinical animal research for six treatment interventions

    Get PDF
    The harm benefit analysis (HBA) is the cornerstone of animal research regulation and is considered to be a key ethical safeguard for animals. The HBA involves weighing the anticipated benefits of animal research against its predicted harms to animals but there are doubts about how objective and accountable this process is.i. To explore the harms to animals involved in pre-clinical animal studies and to assess these against the benefits for humans accruing from these studies; ii. To test the feasibility of conducting this type of retrospective HBA.Data on harms were systematically extracted from a sample of pre-clinical animal studies whose clinical relevance had already been investigated by comparing systematic reviews of the animal studies with systematic reviews of human studies for the same interventions (antifibrinolytics for haemorrhage, bisphosphonates for osteoporosis, corticosteroids for brain injury, Tirilazad for stroke, antenatal corticosteroids for neonatal respiratory distress and thrombolytics for stroke). Clinical relevance was also explored in terms of current clinical practice. Harms were categorised for severity using an expert panel. The quality of the research and its impact were considered. Bateson's Cube was used to conduct the HBA.The most common assessment of animal harms by the expert panel was 'severe'. Reported use of analgesia was rare and some animals (including most neonates) endured significant procedures with no, or only light, anaesthesia reported. Some animals suffered iatrogenic harms. Many were kept alive for long periods post-experimentally but only 1% of studies reported post-operative care. A third of studies reported that some animals died prior to endpoints. All the studies were of poor quality. Having weighed the actual harms to animals against the actual clinical benefits accruing from these studies, and taking into account the quality of the research and its impact, less than 7% of the studies were permissible according to Bateson's Cube: only the moderate bisphosphonate studies appeared to minimise harms to animals whilst being associated with benefit for humans.This is the first time the accountability of the HBA has been systematically explored across a range of pre-clinical animal studies. The regulatory systems in place when these studies were conducted failed to safeguard animals from severe suffering or to ensure that only beneficial, scientifically rigorous research was conducted. Our findings indicate a pressing need to: i. review regulations, particularly those that permit animals to suffer severe harms; ii. reform the processes of prospectively assessing pre-clinical animal studies to make them fit for purpose; and iii. systematically evaluate the benefits of pre-clinical animal research to permit a more realistic assessment of its likely future benefits

    3-D Ultrastructure of O. tauri: Electron Cryotomography of an Entire Eukaryotic Cell

    Get PDF
    The hallmark of eukaryotic cells is their segregation of key biological functions into discrete, membrane-bound organelles. Creating accurate models of their ultrastructural complexity has been difficult in part because of the limited resolution of light microscopy and the artifact-prone nature of conventional electron microscopy. Here we explored the potential of the emerging technology electron cryotomography to produce three-dimensional images of an entire eukaryotic cell in a near-native state. Ostreococcus tauri was chosen as the specimen because as a unicellular picoplankton with just one copy of each organelle, it is the smallest known eukaryote and was therefore likely to yield the highest resolution images. Whole cells were imaged at various stages of the cell cycle, yielding 3-D reconstructions of complete chloroplasts, mitochondria, endoplasmic reticula, Golgi bodies, peroxisomes, microtubules, and putative ribosome distributions in-situ. Surprisingly, the nucleus was seen to open long before mitosis, and while one microtubule (or two in some predivisional cells) was consistently present, no mitotic spindle was ever observed, prompting speculation that a single microtubule might be sufficient to segregate multiple chromosomes

    Surface Chemistry of Perfluoropolyethers and Hydrogenated Analogs: Are Studies of Model Compounds Useful?

    Get PDF
    We have studied adsorption, desorption, and decomposition of ethers on Ru(001), an atomically-smooth metal surface. We have compared diethers with monoethers, and fluorinated ethers with hydrogenated ethers. The number of ether linkages does not strongly influence adsorption bond strength, nor the extent of decomposition. Fluorination does weaken the adsorption bond strength and prevents decomposition. These studies suggest that the surface properties of monomeric ethers can be used to predict properties of oligomeric, and perhaps even polymeric, ethers

    An SU(N) Mott insulator of an atomic Fermi gas realized by large-spin Pomeranchuk cooling

    Get PDF
    The Hubbard model, containing only the minimum ingredients of nearest neighbor hopping and on-site interaction for correlated electrons, has succeeded in accounting for diverse phenomena observed in solid-state materials. One of the interesting extensions is to enlarge its spin symmetry to SU(N>2), which is closely related to systems with orbital degeneracy. Here we report a successful formation of the SU(6) symmetric Mott insulator state with an atomic Fermi gas of ytterbium (173Yb) in a three-dimensional optical lattice. Besides the suppression of compressibility and the existence of charge excitation gap which characterize a Mott insulating phase, we reveal an important difference between the cases of SU(6) and SU(2) in the achievable temperature as the consequence of different entropy carried by an isolated spin. This is analogous to Pomeranchuk cooling in solid 3He and will be helpful for investigating exotic quantum phases of SU(N) Hubbard system at extremely low temperatures.Comment: 20 pages, 6 figures, to appear in Nature Physic
    corecore