16,529 research outputs found
Investigation of strength of isolated vertebrae, phase IV Final technical report, 29 Oct. 1965 - 28 Oct. 1966
Dynamic strength measurements of human vertebrae under axial compressio
Investigation of strength of isolated vertebrae Quarterly report, 30 Jan. - 29 May 1966
Strength of human vertebrae under various static and dynamic load
Coexistence of Antiferromagnetism and Superconductivity in Electron-doped High-Tc Superconductors
We present magnetotransport evidence for antiferromagnetism in films of the
electron-doped cuprates PrCeCuO. Our results show clear
signature of static antiferromagnetism up to optimal doping x=0.15, with a
quantum phase transition close to x=0.16, and a coexistence of static
antiferromagnetism and superconductivity for 0.12x0.15
E-cigarette use among women of reproductive age: Impulsivity, cigarette smoking status, and other risk factors.
INTRODUCTION: The study aim was to examine impulsivity and other risk factors for e-cigarette use among women of reproductive age comparing current daily cigarette smokers to never cigarette smokers. Women of reproductive age are of special interest because of the additional risk that tobacco and nicotine use represents should they become pregnant.
METHOD: Survey data were collected anonymously online using Amazon Mechanical Turk in 2014. Participants were 800 women ages 24-44years from the US. Half (n=400) reported current, daily smoking and half (n=400) reported smokingsociodemographics, tobacco/nicotine use, and impulsivity (i.e., delay discounting & Barratt Impulsiveness Scale). Predictors of smoking and e-cigarette use were examined using logistic regression.
RESULTS: Daily cigarette smoking was associated with greater impulsivity, lower education, past illegal drug use, and White race/ethnicity. E-cigarette use in the overall sample was associated with being a cigarette smoker and greater education. E-cigarette use among current smokers was associated with increased nicotine dependence and quitting smoking; among never smokers it was associated with greater impulsivity and illegal drug use. E-cigarette use was associated with hookah use, and for never smokers only with use of cigars and other nicotine products.
CONCLUSIONS: E-cigarette use among women of reproductive age varies by smoking status, with use among current smokers reflecting attempts to quit smoking whereas among non-smokers use may be a marker of a more impulsive repertoire that includes greater use of alternative tobacco products and illegal drugs
Dynamic Creation and Annihilation of Metastable Vortex Phase as a Source of Excess Noise
The large increase in voltage noise, commonly observed in the vicinity of the
peak-effect in superconductors, is ascribed to a novel noise mechanism. A
strongly pinned metastable disordered vortex phase, which is randomly generated
at the edges and annealed into ordered phase in the bulk, causes large
fluctuations in the integrated critical current of the sample. The excess noise
due to this dynamic admixture of two distinct phases is found to display
pronounced reentrant behavior. In the Corbino geometry the injection of the
metastable phase is prevented and, accordingly, the excess noise disappearsComment: 5 pages 3 figures. Accepted for publication in Europhysics letter
Person-centred oral hydration care for older people with dementia admitted to acute hospital wards: Empirical research qualitative.
To conduct an in-depth exploration of oral hydration care provided to people living with dementia in acute hospital wards, using a person-centred care framework. Oral hydration care is an important, yet rarely explored aspect of fundamental care for people with dementia admitted to acute hospitals. Using person-centred care as a conceptual framework we investigated how oral hydration care is delivered for people living with dementia in acute hospital wards. A qualitative, multiple-case study. The cases were three acute wards in one hospital. Direct observation of care for 13 people with dementia (132 h), semistructured interviews with ward staff (n = 28), ward leaders (n = 4), organisational leaders (n = 5), people with dementia (n = 6), their relatives (n = 5), documentary analysis of clinical inpatient records (n = 26) and relevant hospital policies. Data were analysed using framework analysis. Four themes were identified: (1) The acute hospital: oral hydration is obscured and not prioritised (2) Overshadowing of oral hydration at ward level (3) Siloed nature of hydration roles (4) Strategies for, and barriers to, delivering person-centred oral hydration care. This study combines the concept of person-centred care and oral hydration care for people living with dementia admitted to acute hospital wards, demonstrating that person-centred hydration care was complex and not prioritised. Nurses should consider means of improving prioritisation and cohesive delivery of person-centred hydration care in acute hospital wards. [Abstract copyright: © 2023 The Authors. Journal of Clinical Nursing published by John Wiley & Sons Ltd.
Role of oxygen in the electron-doped superconducting cuprates
We report on resistivity and Hall measurements in thin films of the
electron-doped superconducting cuprate PrCeCuO.
Comparisons between x = 0.17 samples subjected to either ion-irradiation or
oxygenation demonstrate that changing the oxygen content has two separable
effects: 1) a doping effect similar to that of cerium, and 2) a disorder
effect. These results are consistent with prior speculations that apical oxygen
removal is necessary to achieve superconductivity in this compound.Comment: 5 pages, 5 figure
Structure factor and thermodynamics of rigid dendrimers in solution
The ''polymer reference interaction site model'' (PRISM) integral equation
theory is used to determine the structure factor of rigid dendrimers in
solution. The theory is quite successful in reproducing experimental structure
factors for various dendrimer concentrations. In addition, the structure factor
at vanishing scattering vector is calculated via the compressibility equation
using scaled particle theory and fundamental measure theory. The results as
predicted by both theories are systematically smaller than the experimental and
PRISM data for platelike dendrimers.Comment: 7 pages, 5 figures, submitte
Adaptive Measurements in the Optical Quantum Information Laboratory
Adaptive techniques make practical many quantum measurements that would
otherwise be beyond current laboratory capabilities. For example: they allow
discrimination of nonorthogonal states with a probability of error equal to the
Helstrom bound; they allow measurement of the phase of a quantum oscillator
with accuracy approaching (or in some cases attaining) the Heisenberg limit;
and they allow estimation of phase in interferometry with a variance scaling at
the Heisenberg limit, using only single qubit measurement and control. Each of
these examples has close links with quantum information, in particular
experimental optical quantum information: the first is a basic quantum
communication protocol; the second has potential application in linear optical
quantum computing; the third uses an adaptive protocol inspired by the quantum
phase estimation algorithm. We discuss each of these examples, and their
implementation in the laboratory, but concentrate upon the last, which was
published most recently [Higgins {\em et al.}, Nature vol. 450, p. 393, 2007].Comment: 12 pages, invited paper to be published in IEEE Journal of Selected
Topics in Quantum Electronics: Quantum Communications and Information Scienc
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