367 research outputs found
The role of internet resources in health decision-making::a qualitative study
Objective: Internet resources remain important for health information and advice but their specific role in decision-making is understudied, often assumed and remains unclear. In this article, we examine the different ways in which internet resources play a role in health decision-making within the context of distributed decision-making.
Methods: We conducted semi-structured interviews with thirty-seven people in the United Kingdom who reported using the internet in relation to decision-making and represented a range of long and short-term health conditions. The interviews focused on decision-making activities across different settings and in relation to different stakeholders to understand how internet resources play a role in these activities. We carried out a thematic analysis of the interviews.
Results: We identified three main ways in which internet resources played a role in health decision-making. A supportive role (as a decision crutch), a stimulating role (as a decision initiator), and an interactional role (impacting on the doctor–patient relationship). These three roles spanned different resources and illustrated how the decision-making process can be impacted by the encounters people have with technology – specifically internet based health resources, in different ways and at different time points.
Conclusions: Examining health decisions in respect to internet resources highlights the complex and distributed nature of decision-making alongside the complexity of online health information sourcing. We discuss the role of internet resources in relation to the increasing importance of online personal experiences and their relevance within shared decision-making
Hadamard Products of Product Operators and the Design of Gradient-Diffusion Experiments for Simulating Decoherence by NMR Spectroscopy
An extension of the product operator formalism of NMR is introduced, which
uses the Hadamard matrix product to describe many simple spin 1/2 relaxation
processes. The utility of this formalism is illustrated by deriving NMR
gradient-diffusion experiments to simulate several decoherence models of
interest in quantum information processing, along with their Lindblad and Kraus
representations. Gradient-diffusion experiments are also described for several
more complex forms of decoherence, including the well-known collective
isotropic model. Finally, it is shown that the Hadamard formalism gives a
concise representation of decoherence with arbitrary correlations among the
fluctuating fields at the different spins involved, and that this can be
applied to both decoherence (T2) as well as nonadiabatic relaxation (T1)
processes.Comment: RevTeX, 11 page single-spaced preprint, no figures. Version two has
new title, abstract, introduction & conclusions, while the main body of the
text remains substantially the sam
Mechanisms of proton-proton inelastic cross-section growth in multi-peripheral model within the framework of perturbation theory. Part 2
We demonstrate a new technique for calculating proton-proton inelastic
cross-section, which allows one by application of the Laplace' method replace
the integrand in the integral for the scattering amplitude in the vicinity of
the maximum point by expression of Gaussian type. This in turn, allows one to
overcome the computational difficulties for the calculation of the integrals
expressing the cross section to sufficiently large numbers of particles. We
have managed to overcome these problems in calculating the proton-proton
inelastic cross-section for production (n \le 8) number of secondary particles
in within the framework of \phi^3 model. As the result the obtained dependence
of inelastic cross-section and total scattering cross-section on the energy
\sqrt{s} are qualitative agrees with the experimental data. Such description of
total cross-section behavior differs considerably from existing now
description, where reggeons exchange with the intercept greater than unity is
considered.Comment: 11 pages, 10 figures (v3: some inaccuracies corrected
Simulation of the short-range order in disordered cubic titanium monoxide TiO1.0
A model of the atomic structure with the short-range order in the vacancy distribution for the disordered cubic phase of titanium monoxide TiO1.0 has been proposed. The effect of the short-range order on the electronic structure and the stability of the compound has been studied by the supercell method within the DFT-GGA approximation with the use of pseudopotentials. It has been established that the appearance of the short-range order considerably decreases the total energy. The decrease in the energy is comparable with the energy gain during the ordering of the vacancies according to the type of monoclinic superstructure Ti5O5 to the long-range order parameter η = 0.7. It has been shown that the discrepancies between the theoretical and experimental electronic spectra of titanium monoxide can be explained by allowance for the short range order. © 2013 Pleiades Publishing, Ltd
Quantum Codes for Controlling Coherent Evolution
Control over spin dynamics has been obtained in NMR via coherent averaging,
which is implemented through a sequence of RF pulses, and via quantum codes
which can protect against incoherent evolution. Here, we discuss the design and
implementation of quantum codes to protect against coherent evolution. A
detailed example is given of a quantum code for protecting two data qubits from
evolution under a weak coupling (Ising) term in the Hamiltonian, using an
``isolated'' ancilla which does not evolve on the experimental time scale. The
code is realized in a three-spin system by liquid-state NMR spectroscopy on
13C-labelled alanine, and tested for two initial states. It is also shown that
for coherent evolution and isolated ancillae, codes exist that do not require
the ancillae to initially be in a (pseudo-)pure state. Finally, it is shown
that even with non-isolated ancillae quantum codes exist which can protect
against evolution under weak coupling. An example is presented for a six qubit
code that protects two data spins to first order.Comment: Reformatted single spaced with figures incorporated into text (18
pages, 6 figures, PDF only, submitted to J. Chem. Phys.
Spintronics and Quantum Dots for Quantum Computing and Quantum Communication
Control over electron-spin states, such as coherent manipulation, filtering
and measurement promises access to new technologies in conventional as well as
in quantum computation and quantum communication. We review our proposal of
using electron spins in quantum confined structures as qubits and discuss the
requirements for implementing a quantum computer. We describe several
realizations of one- and two-qubit gates and of the read-in and read-out tasks.
We discuss recently proposed schemes for using a single quantum dot as
spin-filter and spin-memory device. Considering electronic EPR pairs needed for
quantum communication we show that their spin entanglement can be detected in
mesoscopic transport measurements using metallic as well as superconducting
leads attached to the dots.Comment: Prepared for Fortschritte der Physik special issue, Experimental
Proposals for Quantum Computation. 15 pages, 5 figures; typos corrected,
references adde
Is mindfulness Buddhist? (and why it matters).
Modern exponents of mindfulness meditation promote the therapeutic effects of "bare attention"--a sort of non-judgmental, non-discursive attending to the moment-to-moment flow of consciousness. This approach to Buddhist meditation can be traced to Burmese Buddhist reform movements of the first half of the 20th century, and is arguably at odds with more traditional Theravāda Buddhist doctrine and meditative practices. But the cultivation of present-centered awareness is not without precedent in Buddhist history; similar innovations arose in medieval Chinese Zen (Chan) and Tibetan Dzogchen. These movements have several things in common. In each case the reforms were, in part, attempts to render Buddhist practice and insight accessible to laypersons unfamiliar with Buddhist philosophy and/or unwilling to adopt a renunciatory lifestyle. In addition, these movements all promised astonishingly quick results. And finally, the innovations in practice were met with suspicion and criticism from traditional Buddhist quarters. Those interested in the therapeutic effects of mindfulness and bare attention are often not aware of the existence, much less the content, of the controversies surrounding these practices in Asian Buddhist history
A Study of Quantum Error Correction by Geometric Algebra and Liquid-State NMR Spectroscopy
Quantum error correcting codes enable the information contained in a quantum
state to be protected from decoherence due to external perturbations. Applied
to NMR, quantum coding does not alter normal relaxation, but rather converts
the state of a ``data'' spin into multiple quantum coherences involving
additional ancilla spins. These multiple quantum coherences relax at differing
rates, thus permitting the original state of the data to be approximately
reconstructed by mixing them together in an appropriate fashion. This paper
describes the operation of a simple, three-bit quantum code in the product
operator formalism, and uses geometric algebra methods to obtain the
error-corrected decay curve in the presence of arbitrary correlations in the
external random fields. These predictions are confirmed in both the totally
correlated and uncorrelated cases by liquid-state NMR experiments on
13C-labeled alanine, using gradient-diffusion methods to implement these
idealized decoherence models. Quantum error correction in weakly polarized
systems requires that the ancilla spins be prepared in a pseudo-pure state
relative to the data spin, which entails a loss of signal that exceeds any
potential gain through error correction. Nevertheless, this study shows that
quantum coding can be used to validate theoretical decoherence mechanisms, and
to provide detailed information on correlations in the underlying NMR
relaxation dynamics.Comment: 33 pages plus 6 figures, LaTeX article class with amsmath & graphicx
package
Financial Aspects of Technological Concept for Energy Efficiency Enhancement during Stripper Wells Development in Tomsk Region
The issue of operating costs cutting in terms of falling oil prices on the world market actualizes the challenge to find technological solutions to reduce electricity consumption during well operation. This is especially important for stripped-wells of small deposits in Tomsk region. The correlation analysis between the cost of oil production, electricity, heat and fuel consumption during the extraction of one ton of oil allowed the authors to focus on the financial aspect of such technological solutions like periodic well operation in the Shinginskoye field as well as to recommend the application of this method at the other fields in Tomsk region
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