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A pilot study of a text messaging intervention to modify illness and medication beliefs amongst patients diagnosed with inflammatory bowel disease
Intentional and unintentional medication non-adherence is a particular challenge for patients with inflammatory bowel disease (IBD). Non-adherence can affect patients’ quality of life, which can result in unfavorable treatment outcomes, more hospitalizations, and higher healthcare-related costs. The purpose of this study was to assess whether a tailored text message intervention designed to modify illness and medication adherence beliefs in patients with IBD would increase treatment compliance and change patients’ illness perceptions and medication concerns. This pilot study utilized a pre-test-post-test non-randomized design. A sample of 32 IBD patients was recruited within the UK. Participants’ medication beliefs and illness perception scores determined the set of tailored daily text messages, which were sent to patients over duration of 12 weeks. Medication adherence increased post-intervention, as “forgetting to take medication” decreased while “never” forgetting to take medication increased over time. A significant increase in treatment control and coherence and a decreased level of concern surrounding their condition was evident. Participants’ level of concern towards their medications changed during the 12 weeks, with a baseline mean concern score of 3.08 (.57) in comparison to the 12 weeks mean concern score of 2.89 (.59), which is statistically different, t (31) = 2.16, p < .038, r = .36 (medium effect). Sixty-six percent of participants from the baseline were aware of the necessity of their medication: “without my medication I would become ill.” The results have direct implications for improving medication adherence and changing illness and medication beliefs. This study validated the benefits of text messages and highlighted the importance of addressing these beliefs in order to understand the reasons for non-adherence fully
NMR analogues of the quantum Zeno effect
We describe Nuclear Magnetic Resonance (NMR) demonstrations of the quantum
Zeno effect, and discuss briefly how these are related to similar phenomena in
more conventional NMR experiments.Comment: 8 pages including 4 figures; intended as a possible answer to Malcolm
Levitt's question at the 2005 Magnetic Resonanace GRC: "What is the NMR
analogue of the quantum Zeno effect?". In press at Physics Letters
Photonic qubits, qutrits and ququads accurately prepared and delivered on demand
Reliable encoding of information in quantum systems is crucial to all
approaches to quantum information processing or communication. This applies in
particular to photons used in linear optics quantum computing (LOQC), which is
scalable provided a deterministic single-photon emission and preparation is
available. Here, we show that narrowband photons deterministically emitted from
an atom-cavity system fulfill these requirements. Within their 500 ns coherence
time, we demonstrate a subdivision into d time bins of various amplitudes and
phases, which we use for encoding arbitrary qu-d-its. The latter is done
deterministically with a fidelity >95% for qubits, verified using a newly
developed time-resolved quantum-homodyne method.Comment: 5 pages, 4 figure
Electrical activity of carbon-hydrogen centers in Si
The electrical activity of Cs-H defects in Si has been investigated in a combined modeling and experimental study. High-resolution Laplace capacitance spectroscopy with the uniaxial stress technique has been used to measure the stress-energy tensor and the results are compared with theoretical modeling. At low temperatures, implanted H is trapped as a negative-U center with a donor level in the upper half of the gap. However, at higher temperatures, H migrates closer to the carbon impurity and the donor level falls, crossing the gap. At the same time, an acceptor level is introduced into the upper gap making the defect a positive-U center
High frequency sampling of a continuous-time ARMA process
Continuous-time autoregressive moving average (CARMA) processes have recently
been used widely in the modeling of non-uniformly spaced data and as a tool for
dealing with high-frequency data of the form , where
is small and positive. Such data occur in many fields of application,
particularly in finance and the study of turbulence. This paper is concerned
with the characteristics of the process (Y_{n\Delta})_{n\in\bbz}, when
is small and the underlying continuous-time process (Y_t)_{t\in\bbr}
is a specified CARMA process.Comment: 13 pages, submitte
Entanglement distribution by an arbitrarily inept delivery service
We consider the scenario where a company C manufactures in bulk pure
entangled pairs of particles, each pair intended for a distinct pair of distant
customers. Unfortunately, its delivery service is inept - the probability that
any given customer pair receives its intended particles is S, and the customers
cannot detect whether an error has occurred. Remarkably, no matter how small S
is, it is still possible for C to distribute entanglement by starting with
non-maximally entangled pairs. We determine the maximum entanglement
distributable for a given S, and also determine the ability of the parties to
perform nonlocal tasks with the qubits they receive.Comment: 5 pages, 3 figures. v2 includes minor change
Sharing Polarization within Quantum Subspaces
Given an ensemble of n spins, at least some of which are partially polarized,
we investigate the sharing of this polarization within a subspace of k spins.
We assume that the sharing results in a pseudopure state, characterized by a
single purity parameter which we call the bias. As a concrete example we
consider ensembles of spin-1/2 nuclei in liquid-state nuclear magnetic
resonance (NMR) systems. The shared bias levels are compared with some current
entanglement bounds to determine whether the reduced subspaces can give rise to
entangled states.Comment: 7 pages, 3 figure
Geometric Aspects of Composite Pulses
Unitary operations acting on a quantum system must be robust against
systematic errors in control parameters for reliable quantum computing.
Composite pulse technique in nuclear magnetic resonance (NMR) realises such a
robust operation by employing a sequence of possibly poor quality pulses. In
this article, we demonstrate that two kinds of composite pulses, one
compensates for a pulse length error in a one-qubit system and the other
compensates for a J-coupling error in a twoqubit system, have vanishing
dynamical phase and thereby can be seen as geometric quantum gates, which
implement unitary gates by the holonomy associated with dynamics of cyclic
vectors defined in the text.Comment: 20 pages, 4 figures. Accepted for publication in Philosophical
Transactions of the Royal Society
Theory Including Future Not Excluded -- Formulation of Complex Action Theory II --
We study a complex action theory (CAT) whose path runs over not only past but
also future. We show that if we regard a matrix element defined in terms of the
future state at time and the past state at time as an expectation
value in the CAT, then we are allowed to have the Heisenberg equation, the
Ehrenfest's theorem and the conserved probability current density. In addition
we show that the expectation value at the present time of a future-included
theory for large and large corresponds to that of a
future-not-included theory with a proper inner product for large .
Hence the CAT with future explicitly present in the formalism and influencing
in principle the past is not excluded phenomenologically, because the effects
are argued to be very small in the present era. Furthermore we explicitly
derive the Schr\"{o}dinger equation and Hamiltonian for the future state via
path integral, and confirm that the Hamiltonian is given by the Hermitian
conjugate of the Hamiltonian for the past state.Comment: Latex 28 pages, 2 figures, typos corrected, presentation improved,
the final version to appear in Prog.Theor.Exp.Phys (v4) The errors related to
the Hermitian operator are corrected. A missed -dependent
normalization factor is properly considered in the appendix. The errors and
typos mentioned in the erratum of PTEP are correcte
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