1,382 research outputs found

    D-region ion chemistry

    Get PDF
    D-region ion chemistry, nitrogen oxides and oxygen allotropes in mesosphere, and ionization source

    Back to the Basics with Environmental Hygiene

    Get PDF
    Environmental hygiene is fundamental in preventing the transmission of pathogens that can cause health care-associated infections (HAIs). Inanimate surfaces within the patient’s environment are defined as high-touch surfaces and include areas such as bedrails, tray tables, call lights, telephones, any equipment that is attached to the patient, and the computer on wheels. HAIs develop during hospitalization and occur within 48 to 72 hours of admission or within 10 days after hospital discharge (CDC, 2014; Collins, 2008). HAIs increase the morbidity, mortality, and hospital expenditures; and critically ill patients are at greater risk for HAIs because of their compromised immune systems, prolonged indwelling medical devices, multiple invasive procedures, and antibiotic use (CDC, 2014; Collins, 2008). A 26-bed cardiac intensive care unit implemented a high-touch surface cleaning protocol in order to decrease HAI rates and improve overall environmental hygiene within the patient’s immediate surroundings. The pre- and post-survey results determined that the protocol was easily implemented into daily practice and the intervention improved environmental hygiene within the patient’s immediate environment

    When correction turns positive: Processing corrective prosody in Dutch

    Get PDF
    Current research on spoken language does not provide a consistent picture as to whether prosody, the melody and rhythm of speech, conveys a specific meaning. Perception studies show that English listeners assign meaning to prosodic patterns, and, for instance, associate some accents with contrast, whereas Dutch listeners behave more controversially. In two ERP studies we tested how Dutch listeners process words carrying two types of accents, which either provided new information (new information accents) or corrected information (corrective accents), both in single sentences (experiment 1) and after corrective and new information questions (experiment 2). In both experiments corrective accents elicited a sustained positivity as compared to new information accents, which started earlier in context than in single sentences. The positivity was not modulated by the nature of the preceding question, suggesting that the underlying neural mechanism likely reflects the construction of an interpretation to the accented word, either by identifying an alternative in context or by inferring it when no context is present. Our experimental results provide strong evidence for inferential processes related to prosodic contours in Dutc

    Extra-matrix Mg\u3csup\u3e2+\u3c/sup\u3e Limits Ca\u3csup\u3e2+\u3c/sup\u3e Uptake and Modulates Ca\u3csup\u3e2+\u3c/sup\u3e Uptake-independent Respiration and Redox State in Cardiac Isolated Mitochondria

    Get PDF
    Cardiac mitochondrial matrix (m) free Ca2+ ([Ca2+]m) increases primarily by Ca2+ uptake through the Ca2+ uniporter (CU). Ca2+ uptake via the CU is attenuated by extra-matrix (e) Mg2+ ([Mg2+]e). How [Ca2+]m is dynamically modulated by interacting physiological levels of [Ca2+]e and [Mg2+]e and how this interaction alters bioenergetics are not well understood. We postulated that as [Mg2+]e modulates Ca2+ uptake via the CU, it also alters bioenergetics in a matrix Ca2+–induced and matrix Ca2+–independent manner. To test this, we measured changes in [Ca2+]e, [Ca2+]m, [Mg2+]e and [Mg2+]m spectrofluorometrically in guinea pig cardiac mitochondria in response to added CaCl2 (0–0.6 mM; 1 mM EGTA buffer) with/without added MgCl2 (0–2 mM). In parallel, we assessed effects of added CaCl2 and MgCl2 on NADH, membrane potential (ΔΨm), and respiration. We found that \u3e0.125 mM MgCl2 significantly attenuated CU-mediated Ca2+ uptake and [Ca2+]m. Incremental [Mg2+]e did not reduce initial Ca2+uptake but attenuated the subsequent slower Ca2+ uptake, so that [Ca2+]m remained unaltered over time. Adding CaCl2 without MgCl2 to attain a [Ca2+]m from 46 to 221 nM enhanced state 3 NADH oxidation and increased respiration by 15 %; up to 868 nM [Ca2+]m did not additionally enhance NADH oxidation or respiration. Adding MgCl2 did not increase [Mg2+]m but it altered bioenergetics by its direct effect to decrease Ca2+ uptake. However, at a given [Ca2+]m, state 3 respiration was incrementally attenuated, and state 4 respiration enhanced, by higher [Mg2+]e. Thus, [Mg2+]e without a change in [Mg2+]m can modulate bioenergetics independently of CU-mediated Ca2+ transport

    Entanglement of Atomic Qubits using an Optical Frequency Comb

    Full text link
    We demonstrate the use of an optical frequency comb to coherently control and entangle atomic qubits. A train of off-resonant ultrafast laser pulses is used to efficiently and coherently transfer population between electronic and vibrational states of trapped atomic ions and implement an entangling quantum logic gate with high fidelity. This technique can be extended to the high field regime where operations can be performed faster than the trap frequency. This general approach can be applied to more complex quantum systems, such as large collections of interacting atoms or molecules.Comment: 4 pages, 5 figure

    A Modified Approach to Single-Spin Detection Using Magnetic Resonance Force Microscopy

    Full text link
    The magnetic moment of a single spin interacting with a cantilever in magnetic resonance force microscopy (MRFM) experiences quantum jumps in orientation rather than smooth oscillations. These jumps cannot be detected by a conventional MRFM based on observation of driven resonant oscillations of a cantilever. In this paper, we propose a method which will allow detection of the magnetic signal from a single spin using a modification of a conventional MRFM. We estimate the opportunity to detect the magnetic signal from a single proton.Comment: 4 pages LaTex, 4 figures in GIF forma

    High-Impact Practices: An Analysis of Select University and Business School Programs

    Get PDF
    Colleges and universities are finding new ways to enhance the academic environment with high-impact programs such as student-based research, internships and international study abroad programs. Research has shown that students learn most when they are more engaged in the experience rather than passive participants. This exploratory study examines high-impact opportunities for undergraduate university students in the U.S. Web sites and other materials from 90 randomly selected AACSB and ACBSP member schools were reviewed to determine how each incorporates high-impact educational practices into their overall university programs and in their business school programs. Three high-impact programs were examined: undergraduate research, internships and global learning opportunities. Recommendations for future high-impact educational practices are discussed. High Impact (HI) programs are prevalent in U.S. colleges and universities. There is a significant positive relationship between high-impact activities and graduation rates. Institutions that have healthier high impact practices have better graduation rates. Larger schools and schools with AACSB accreditation also have stronger high impact practices devoted specifically to business schools. Doctoral granting institutions scored higher in all three practices analyzed in this study. Undergraduate research is the area in which high-impact ratings were the lowest

    Prospects for precision measurements of atomic helium using direct frequency comb spectroscopy

    Full text link
    We analyze several possibilities for precisely measuring electronic transitions in atomic helium by the direct use of phase-stabilized femtosecond frequency combs. Because the comb is self-calibrating and can be shifted into the ultraviolet spectral region via harmonic generation, it offers the prospect of greatly improved accuracy for UV and far-UV transitions. To take advantage of this accuracy an ultracold helium sample is needed. For measurements of the triplet spectrum a magneto-optical trap (MOT) can be used to cool and trap metastable 2^3S state atoms. We analyze schemes for measuring the two-photon 23S→43S2^3S \to 4^3S interval, and for resonant two-photon excitation to high Rydberg states, 23S→33P→n3S,D2^3S \to 3^3P \to n^3S,D. We also analyze experiments on the singlet-state spectrum. To accomplish this we propose schemes for producing and trapping ultracold helium in the 1^1S or 2^1S state via intercombination transitions. A particularly intriguing scenario is the possibility of measuring the 11S→21S1^1S \to 2^1S transition with extremely high accuracy by use of two-photon excitation in a magic wavelength trap that operates identically for both states. We predict a ``triple magic wavelength'' at 412 nm that could facilitate numerous experiments on trapped helium atoms, because here the polarizabilities of the 1^1S, 2^1S and 2^3S states are all similar, small, and positive.Comment: Shortened slightly and reformatted for Eur. Phys. J.
    • …
    corecore