14 research outputs found

    Coupled resonator based wireless power transfer for bioelectronics

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    Implantable and wearable bioelectronics provide the ability to monitor and modulate physiological processes. They represent a promising set of technologies that can provide new treatment for patients or new tools for scientific discovery, such as in long-term studies involving small animals. As these technologies advance, two trends are clear, miniaturization and increased sophistication i.e. multiple channels, wireless bi-directional communication, and responsiveness (closed-loop devices). One primary challenge in realizing miniaturized and sophisticated bioelectronics is powering. Integration and development of wireless power transfer (WPT) technology, however, can overcome this challenge. In this dissertation, I propose the use of coupled resonator WPT for bioelectronics and present a new generalized analysis and optimization methodology, derived from complex microwave bandpass filter synthesis, for maximizing and controlling coupled resonator based WPT performance. This newly developed set of analysis and optimization methods enables system miniaturization while simultaneously achieving the necessary performance to safely power sophisticated bioelectronics. As an application example, a novel coil to coil based coupled resonator arrangement to wirelessly operate eight surface electromyography sensing devices wrapped circumferentially around an able-bodied arm is developed and demonstrated. In addition to standard coil to coil based systems, this dissertation also presents a new form of coupled resonator WPT system built of a large hollow metallic cavity resonator. By leveraging the analysis and optimization methods developed here, I present a new cavity resonator WPT system for long-term experiments involving small rodents for the first time. The cavity resonator based WPT arena exhibits a volume of 60.96 x 60.96 x 30.0 cm3. In comparison to prior state of the art, this cavity resonator system enables nearly continuous wireless operation of a miniature sophisticated device implanted in a freely behaving rodent within the largest space. Finally, I present preliminary work, providing the foundation for future studies, to demonstrate the feasibility of treating segments of the human body as a dielectric waveguide resonator. This creates another form of a coupled resonator system. Preliminary experiments demonstrated optimized coupled resonator wireless energy transfer into human tissue. The WPT performance achieved to an ultra-miniature sized receive coil (2 mm diameter) is presented. Indeed, optimized coupled resonator systems, broadened to include cavity resonator structures and human formed dielectric resonators, can enable the effective use of coupled resonator based WPT technology to power miniaturized and sophisticated bioelectronics

    The Ledger and Times, April 10, 1947

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    Bowdoin Orient v.132, no.1-24 (2000-2001)

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    https://digitalcommons.bowdoin.edu/bowdoinorient-2000s/1001/thumbnail.jp

    Bulletin of the University of New Hampshire undergraduate catalog issue, 1974-1975

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    Evolution of workplace architecture as a consequence of technology development

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    Workplace architecture evolves through, and is informed by, the interactions between people, space and technology. It is important, therefore to consider how the future changes in these three elements might affect workplace design. This research investigates to what extent and how information technology (IT) is changing workplace architecture. Using a mixed method approach (survey and case studies) this research focuses upon design organisations and accountancy firms as being representative of the wide range of work activities undertaken in offices. The survey collected data from 105 organisations in Melbourne, Australia and provides a cross section of the current workplace environment and working habits. Three case studies provide insight into current and emerging office environments including private sector and government facilities as well as emerging organisations hosted in virtual worlds. The result suggests that, whilst IT has changed the workplace, people’s natural rate of absorption of change is slowing the adoption process of IT available today. Therefore, the possible magnitude of change in workplace architecture due to technology development is restrained. Despite the high reliance on ITm office environments are shaped by human traits such as face to face interaction, emotions and physical space dependency. As a consequence, the role of technology as a driver of change is questioned and the role of an enabler of change favoured. The recommendation for architects, facility managers and business managers and business managers is that the workplace should be designed, maintained and managerial styles developed for people to benefit from technology. Inverting the priority by producing spaces and management styles based on what technology can do whilst overlooking people’s needs is likely to produce unsuccessful work environments

    The Look of the Book: Visual Elements in the Experience of Reading from Tristram Shandy to Contemporary Artists\u27 Books

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    In the age of the novel, we read fiction sequentially and unselfconsciously. This practice requires us to ignore the materiality and appearance of books, for these factors disrupt narrative absorption. The Look of the Book explores specific books from England and America whose visual and material characteristics resist and redefine habitual experiences of reading prose. These specimens connect word and image in the book format, and they therefore resist the theories of critics since Gotthold Lessing that have separated visual and verbal modes. Lessing\u27s contemporary, Laurence Sterne, uses visual elements in Tristram Shandy (1760–67) to digress from the reading sequence while furthering the overall narrative. Sterne\u27s techniques also establish a taxonomy of the book\u27s constituent variables. In the twentieth century, as bookmaking technologies became more widely accessible, a printing renaissance brought artists into book design. Vanessa Bell creates images and designs page layouts to amplify her sister Virginia Woolf\u27s ekphrastic fiction in the third decorated edition of Woolf\u27s Kew Gardens (Hogarth Press, 1927). The illustrations change the pace of reading by integrating word, image and book structure. In Tom Phillips\u27 A Humument: A Treated Victorian Novel and Sheherezade: A Flip Book, by artist Janet Zweig and author Holly Anderson, words are inseparable from the visual layout of the page, and the resulting written texts create temporally fractured narratives. These postmodern artists\u27 books show that narrative fiction and the physical novel are both malleable structures. In all of these works, the book composer, who masterminds the visual arrangement of the text, influences the reading experience in ways that have not been explored in the context of literary criticism. As predictions about the \u27death of the book\u27 circulate in the academy and popular media, this dissertation suggests that books can make available complex modes of reading that we generally do not expect from novels. This interdisciplinary approach is essential at a time when images pervade the cultural context and are being integrated more thoroughly into print media

    Before American History

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    Before American History juxtaposes Mexico City’s famous carved Sun Stone with the mounded earthworks found throughout the Midwestern states of the U.S. to examine the project of settler nationalism from the 1780s to the 1840s in two North American republics usually studied separately. As the U.S. and Mexico transformed from European colonies into independent nations—and before war scarred them both—antiquarians and historians compiled and interpreted archives meant to document America’s Indigenous pasts. These settler-colonial understandings of North America’s past deliberately misappropriated Indigenous histories and repurposed them and their material objects as "American antiquities," thereby writing Indigenous pasts out of U.S. and Mexican national histories and national lands and erasing and denigrating Native peoples living in both nascent republics.Christen Mucher creatively recovers the Sun Stone and mounded earthworks as archives of nationalist power and Indigenous dispossession as well as objects that are, at their material base, produced by Indigenous people but settler controlled and settler interpreted. Her approach renders visible the foundational methodologies, materials, and mythologies that created an American history out of and on top of Indigenous worlds and facilitated Native dispossession continent-wide. By writing Indigenous actors out of national histories, Mexican and U.S. elites also wrote them out of their lands, a legacy of erasure and removal that continues when we repeat these eighteenth- and nineteenth-century settler narratives and that reverberates in discussions of immigration, migration, and Nativism today

    Holding Back the Waters: Land Development and the Origins of Levees on the Mississippi, 1720-1845.

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    Man\u27s efforts to control flooding on the Mississippi began about 280 years ago, but the first 130 years has been neglected in scholarly literature. In spite of abundant primary sources, most histories of flood control on the Mississippi revolve around hydraulic engineering and the contributions of state and federal levee bureaucracies---factors which had almost no impact on the creation of the levee system. Engineers did install the first levee at New Orleans and levees on their own plantations in the 1720s, but the extension of the levee line thereafter was almost entirely the work of private land developers supervised at the local level, first by commandants, then by parish and county governments. The soil of the floodplain accumulated over centuries as sediment deposited by overflows. Its fertility laid the basis for plantation agriculture, with the Mississippi as a means of transport, but overflows destroyed farmers\u27 improvements. Native American hunting farmers who moved in concert with overflows were able to coexist with flooding, but did not conceive of land as property. When European kings began to convert swampland into property by means of grants, the prevention of flooding through levees was made a condition of title. Persons who wanted swampland as property built levees to acquire it. People who did not value land, or lacked the means to levee it, moved on and did not become part of the levee-building community. Since levees must be continuous to be effective, developers of the riverside had to submit to regimentation, coercion, and continuous oversight. Liberty was tempered by the demands of the environment. The records of the era 1720 to 1845 tell a story of levee history quite different from that of the engineers\u27 and post-bellum levee bureaucracies. Sources which reveal the levees\u27 origins are various: letters of commandants, parish police jury and county board of police minutes, state levee laws for local bodies, newspaper accounts of floods, travel journals, tax and census records, and private papers. They tell of a vibrant community of land developers who domesticated the swamps with levees in the interest of survival and prosperity

    Bowdoin Orient v.72, no.1-26 (1942-1943)

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    https://digitalcommons.bowdoin.edu/bowdoinorient-1940s/1003/thumbnail.jp

    Does the cigarette smoking influence the perinatal outcome?

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    Cigarette smoking, active or passive, is related to adverse perinatal outcome, and affects breastfeeding. It increases risks of spontaneous abortions, preterm delivery, low birthweight, malformations, placenta previa, abruption. The aim of our study was to evaluate whether cigarette smoking has influence to perinatal outcome. Material : newborns and their mothers admitted to Gynecology&Obstetric Clinic, Skopje, Macedonia. Methods : epidemiological, clinical, statistical. Our results showed high influence of the cigarette smoking to some indicators of perinatal outcome (prematurity, low birthweight, Apgar scores). These finding derive conclusion that cigarette smoking is the most frequent and completely preventable risk factor for the adverse neonatal outcome. Key words: newborn, cigarette smoke, outcome, prematurit
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