15 research outputs found

    Enabling Exploration Missions Now: Applications of On-orbit Staging

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    Future NASA Exploration goals are difficult to meet using current launch vehicle implementations and techniques. We introduce a concept of On-Orbit Staging (OOS) using multiple launches into a Low Earth orbit (LEO) staging area to increase payload mass and reduce overall cost for exploration initiative missions. This concept is a forward-looking implementation of ideas put forth by Oberth and Von Braun to address the total mission design. Applying staging throughout the mission and utilizing technological advances in propulsion efficiency and architecture enable us to show that exploration goals can be met in the next decade. As part of this architecture, we assume the readiness of automated rendezvous, docking, and assembly technology

    Development and Preliminary Trial of a Method of Teaching Chemistry

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    226 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1960.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

    Some aspects of plant succession on abandoned farm lands of southeastern Indiana

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    There is no abstract available for this thesis.Thesis (M.A.

    Some aspects of plant succession on abandoned farm lands of southeastern Indiana

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    There is no abstract available for this thesis.Thesis (M.A.

    Calcium Sensor for Photoacoustic Imaging

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    We introduce a selective and cell-permeable calcium sensor for photo­acoustics (CaSPA), a versatile imaging technique that allows for fast volumetric mapping of photo­absorbing molecules with deep tissue penetration. To optimize for Ca<sup>2+</sup>-dependent photo­acoustic signal changes, we synthesized a selective metallo­chromic sensor with high extinction coefficient, low quantum yield, and high photo­bleaching resistance. Micromolar concentrations of Ca<sup>2+</sup> lead to a robust blue­shift of the absorbance of CaSPA, which translated into an accompanying decrease of the peak photo­acoustic signal. The acetoxy­methyl esterified sensor variant was readily taken up by cells without toxic effects and thus allowed us for the first time to perform live imaging of Ca<sup>2+</sup> fluxes in genetically unmodified cells and heart organoids as well as in zebrafish larval brain via combined fluorescence and photo­acoustic imaging

    Meeting the challenges of neuroimaging genetics

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    As research encompassing neuroimaging and genetics gains momentum, extraordinary information will be uncovered on the genetic architecture of the human brain. However, there are significant challenges to be addressed first. Not the least of these challenges is to accomplish the sample size necessary to detect subtle genetic influences on the morphometry and function of the healthy brain. Aside from sample size, image acquisition and analysis methods need to be refined in order to ensure optimum sensitivity to genetic and complementary environmental influences. Then there is the vexing issue of interpreting the resulting data. We describe how researchers from the east coast of Australia and the west coast of America have embarked upon a collaboration to meet these challenges using data currently being collected from a large-scale twin study, and offer some opinions about future directions in the field

    The causal explanatory functions of medical diagnoses

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    Diagnoses in medicine are often taken to serve as explanations of patients’ symptoms and signs. This article examines how they do so. I begin by arguing that although some instances of diagnostic explanation can be formulated as covering law arguments, they are explanatory neither in virtue of their argumentative structures nor in virtue of general regularities between diagnoses and clinical presentations. I then consider the theory that medical diagnoses explain symptoms and signs by identifying their actual causes in particular cases. While I take this to be largely correct, I argue that for a diagnosis to function as a satisfactory causal explanation of a patient’s symptoms and signs, it also needs to be supplemented by understanding the mechanisms by which the identified cause produces the symptoms and signs. This mechanistic understanding comes not from the diagnosis itself, but rather from the theoretical framework within which the physician operates
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