9,713 research outputs found

    Nurses\u27 Alumnae Association Bulletin - Volume 3 Number 5

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    Jefferson Marches On Christmas Packages The United States Cadet Nurse Corps and Jefferson Medical College Hospital Attention Promotions Welcome, Miss Hopkins Student Nurse Activities Scholarship Girls Taking Anaesthesia Our Office and Teaching Staff Message from the President News Bulletins Information Please! Coming Events Graduate Nurses\u27 Chorus Condolences Emergency Nursing Penicillin Organized Staff - 1943-1944 New Positions New Alumnae News of Our Doctors Doctors in Army Army Nurse Corps Navy Nurse Corps Engagements Marriages New Arrival

    Applications of radio interferometry to navigation

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    Radio astronomy experiments have demonstrated the feasibility of making precise position measurements using interferometry techniques. The application of this method to navigation and marine geodesy is discussed, and comparisons are made with existing navigation systems. The very long baseline technique, with a master station, can use either an artificial satellite or natural sources as position references; a high-speed data link is required. A completely ship-borne system is shown to be feasible, at the cost of poorer sensitivity for natural sources. A comparison of Doppler, delay and phase-track modes of operating a very long baseline configuration is made, as that between instantaneous measurements and those where a source can be tracked from horizon to transit. Geometric limitations in latitude and longitude coverage are discussed. The characteristics of natural radio sources, their flux, distribution on the sky, and apparent size are shown to provide a limit on position measurements precision. The atmosphere and frequency standard used both contribute to position measurement uncertainty by affecting interferometric phase

    Probing quasiparticle excitations in a hybrid single electron transistor

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    We investigate the behavior of quasiparticles in a hybrid electron turnstile with the aim of improving its performance as a metrological current source. The device is used to directly probe the density of quasiparticles and monitor their relaxation into normal metal traps. We compare different trap geometries and reach quasiparticle densities below 3um^-3 for pumping frequencies of 20 MHz. Our data show that quasiparticles are excited both by the device operation itself and by the electromagnetic environment of the sample. Our observations can be modelled on a quantitative level with a sequential tunneling model and a simple diffusion equation

    Digital image correlation in dental materials and related research: A review

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    OBJECTIVE: Digital image correlation (DIC) is a non-contact image processing technique for full-field strain measurement. Although DIC has been widely used in engineering and biomechanical fields, it is in the spotlight only recently in dental materials. Therefore, the purpose of this review paper is introducing the working principle of the DIC technique with some modifications and providing further potential applications in various dental materials and related fields. METHODS: The accuracy of the algorithm depending on the environmental characteristics of the DIC technique, as well as the advantages and disadvantages of strain measurement using optical measurements, have been elaborated in dental materials and related fields. Applications to those researches have been classified into the following categories: shrinkage behavior of light-cured resin composite, resin-tooth interface, mechanical properties of tooth structure, crack extension and elastic properties of dental materials, and deformation of dental restoration and prosthesis. This classification and discussion were performed using literature survey and review based on numerous papers in the international journals published over the past 20 years. The future directions for predicting the precise deformation of dental materials under various environments, as well as limitations of the DIC technique, was presented in this review. RESULTS: The DIC technique was demonstrated as a more effective tool to measure full-field polymerization shrinkage of composite resin, even in a simulated clinical condition over the existing methods. Moreover, the DIC combined with other technologies can be useful to evaluate the mechanical behavior of material-tooth interface, dentine structure and restorative and prosthetic materials with high accuracy. Three-dimensional DIC using two cameras extended the measurement range in-plane to out-of-plane, enabling measure of the strain directly on the surface of dental restorations or prosthesis. SIGNIFICANCE: DIC technique is a potential tool for measuring and predicting the full-field deformation/strain of dental materials and actual prostheses in diverse clinical conditions. The versatility of DIC can replace the existing complex sensor devices in those studies

    Magnetodielectric coupling of infrared phonons in single crystal Cu2_{2}OSeO3_{3}

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    Reflection and transmission as a function of temperature have been measured on a single crystal of the magnetoelectric ferrimagnetic compound Cu2_{2}OSeO3_{3} utilizing light spanning the far infrared to the visible portions of the electromagnetic spectrum. The complex dielectric function and optical properties were obtained via Kramers-Kronig analysis and by fits to a Drude-Lortentz model. The fits of the infrared phonons show a magnetodielectric effect near the transition temperature (Tc∼60T_{c}\sim 60~K). Assignments to strong far infrared phonon modes have been made, especially those exhibiting anomalous behavior around the transition temperature

    A room temperature 19-channel magnetic field mapping device for cardiac signals

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    We present a multichannel cardiac magnetic field imaging system built in Fribourg from optical double-resonance Cs vapor magnetometers. It consists of 25 individual sensors designed to record magnetic field maps of the beating human heart by simultaneous measurements on a grid of 19 points over the chest. The system is operated as an array of second order gradiometers using sophisticated digitally controlled feedback loops.Comment: 3 pages, 3 figures, submitted to Applied Physics Letter

    Emerging biogenesis technologies of extracellular vesicles for tissue regenerative therapeutics

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    Extracellular vesicles (EVs), including exosomes, carry the genetic packages of RNA, DNA, and proteins and are heavily involved in cell-cell communications and intracellular signalings. Therefore, EVs are spotlighted as therapeutic mediators for the treatment of injured and dysfunctional tissues as well as biomarkers for the detection of disease status and progress. Several key issues in EVs, including payload content and bioactivity, targeting and bio-imaging ability, and mass-production, need to be improved to enable effective therapeutics and clinical translation. For this, significant efforts have been made recently, including genetic modification, biomolecular and chemical treatment, application of physical/mechanical cues, and 3D cultures. Here we communicate those recent technological advances made mainly in the biogenesis process of EVs or at post-collection stages, which ultimately aimed to improve the therapeutic efficacy in tissue healing and disease curing and the possibility of clinical translation. This communication will help tissue engineers and biomaterial scientists design and produce EVs optimally for tissue regenerative therapeutics

    Population and Harvest Trends of Big Game and Small Game Species

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    This technical document supports the Forest Service’s requirement to assess the status of renewable natural resources as mandated by the Forest and Rangeland Renewable Resources Planning Act of 1974 (RPA). It updates past reports on national and regional trends in population and harvest estimates for species classified as big game and small game. The trends reported here were derived from State Wildlife Agency biologists and supplemented with data from the North American Breeding Bird Survey for those bird species that are commonly sought by upland game hunters. Big game populations and harvests have generally increased over the 1975-2000 period. Small game populations and harvests, particularly those associated with grassland and agricultural systems, show strong patterns of decline. However, population and harvest trends for both groups need to be interpreted with caution because: (1) not all state agencies reported both population and harvest statistics for all species that are commonly sought by recreational hunters, and (2) there were cases of inconsistent reporting at the species level within RPA reporting regions that necessitated aggregating across species. The trends documented here are consistent with trends documented in past RPA reports completed in 1989 and 1999, although those data were also qualified by the same interpretational caveats that apply to the current report. Trends observed generally among big game species were encouraging, but the continual decline in small game populations and harvest remains an important wildlife resource management issue. Until population and harvest monitoring is improved among institutions that share the stewardship responsibility for recreationally important wildlife, national and regional trends will have to be interpreted carefully

    Population and Harvest Trends of Big Game and Small Game Species

    Get PDF
    This technical document supports the Forest Service’s requirement to assess the status of renewable natural resources as mandated by the Forest and Rangeland Renewable Resources Planning Act of 1974 (RPA). It updates past reports on national and regional trends in population and harvest estimates for species classified as big game and small game. The trends reported here were derived from State Wildlife Agency biologists and supplemented with data from the North American Breeding Bird Survey for those bird species that are commonly sought by upland game hunters. Big game populations and harvests have generally increased over the 1975-2000 period. Small game populations and harvests, particularly those associated with grassland and agricultural systems, show strong patterns of decline. However, population and harvest trends for both groups need to be interpreted with caution because: (1) not all state agencies reported both population and harvest statistics for all species that are commonly sought by recreational hunters, and (2) there were cases of inconsistent reporting at the species level within RPA reporting regions that necessitated aggregating across species. The trends documented here are consistent with trends documented in past RPA reports completed in 1989 and 1999, although those data were also qualified by the same interpretational caveats that apply to the current report. Trends observed generally among big game species were encouraging, but the continual decline in small game populations and harvest remains an important wildlife resource management issue. Until population and harvest monitoring is improved among institutions that share the stewardship responsibility for recreationally important wildlife, national and regional trends will have to be interpreted carefully

    Mean-Field Dynamics: Singular Potentials and Rate of Convergence

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    We consider the time evolution of a system of NN identical bosons whose interaction potential is rescaled by N−1N^{-1}. We choose the initial wave function to describe a condensate in which all particles are in the same one-particle state. It is well known that in the mean-field limit N→∞N \to \infty the quantum NN-body dynamics is governed by the nonlinear Hartree equation. Using a nonperturbative method, we extend previous results on the mean-field limit in two directions. First, we allow a large class of singular interaction potentials as well as strong, possibly time-dependent external potentials. Second, we derive bounds on the rate of convergence of the quantum NN-body dynamics to the Hartree dynamics.Comment: Typos correcte
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