414 research outputs found

    A life less lonely: the state of the art in interventions to reduce loneliness in people with mental health problems

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    PURPOSE: There is growing evidence of significant harmful effects of loneliness. Relatively little work has focused on how best to reduce loneliness in people with mental health problems. We aim to present an overview of the current state of the art in loneliness interventions in people with mental health problems, identify relevant challenges, and highlight priorities for future research and implementation. METHODS: A scoping review of the published and grey literature was conducted, as well as discussions with relevant experts, to propose a broad classification system for types of interventions targeting loneliness. RESULTS: We categorised interventions as ‘direct’, targeting loneliness and related concepts in social relationships, and ‘indirect’ broader approaches to well-being that may impact on loneliness. We describe four broad groups of direct interventions: changing cognitions; social skills training and psychoeducation; supported socialisation or having a ‘socially-focused supporter’; and ‘wider community approaches’. The most promising emerging evidence appears to be in ‘changing cognitions’, but, as yet, no approaches have a robust evidence base. Challenges include who is best placed to offer the intervention, how to test such complex interventions, and the stigma surrounding loneliness. CONCLUSIONS: Development of clearly defined loneliness interventions, high-quality trials of effectiveness, and identifying which approaches work best for whom is required. Promising future approaches may include wider community initiatives and social prescribing. It is important to place loneliness and social relationships high on the wider public mental health and research agenda

    Real clocks and the Zeno effect

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    Real clocks are not perfect. This must have an effect in our predictions for the behaviour of a quantum system, an effect for which we present a unified description encompassing several previous proposals. We study the relevance of clock errors in the Zeno effect, and find that generically no Zeno effect can be present (in such a way that there is no contradiction with currently available experimental data). We further observe that, within the class of stochasticities in time addressed here, there is no modification in emission lineshapes.Comment: 12 a4 pages, no figure

    Delocalization in the Anderson model due to a local measurement

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    We study a one-dimensional Anderson model in which one site interacts with a detector monitoring the occupation of that site. We demonstrate that such an interaction, no matter how weak, leads to total delocalization of the Anderson model, and we discuss the experimental consequencesComment: 4 pages, additional explanations added, to appear in Phys. Rev. Let

    Real measurements and Quantum Zeno effect

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    In 1977, Mishra and Sudarshan showed that an unstable particle would never be found decayed while it was continuously observed. They called this effect the quantum Zeno effect (or paradox). Later it was realized that the frequent measurements could also accelerate the decay (quantum anti-Zeno effect). In this paper we investigate the quantum Zeno effect using the definite model of the measurement. We take into account the finite duration and the finite accuracy of the measurement. A general equation for the jump probability during the measurement is derived. We find that the measurements can cause inhibition (quantum Zeno effect) or acceleration (quantum anti-Zeno effect) of the evolution, depending on the strength of the interaction with the measuring device and on the properties of the system. However, the evolution cannot be fully stopped.Comment: 3 figure

    Quantum Anti-Zeno Effect

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    We demonstrate that near threshold decay processes may be accelerated by repeated measurements. Examples include near threshold photodetachment of an electron from a negative ion, and spontaneous emission in a cavity close to the cutoff frequency, or in a photon band gap material.Comment: 4 pages, 3 figure

    Effect of the measurement on the decay rate of a quantum system

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    We investigated the electron tunneling out of a quantum dot in the presence of a continuous monitoring by a detector. It is shown that the Schr\"odinger equation for the whole system can be reduced to new Bloch-type rate equations describing the time-development of the detector and the measured system at once. Using these equations we find that the continuous measurement of the unstable system does not affect its exponential decay, exp(Γt)\exp (-\Gamma t), contrary to expectations based on the Quantum Zeno effect . However, the width of the energy distribution of the tunneling electron is no more Γ\Gamma, but increases due to the decoherence, generated by the detector.Comment: Additional explanations are added. Accepted for publications in Phys. Rev. Let

    Dynamics of Quantum Collapse in Energy Measurements

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    The influence of continuous measurements of energy with a finite accuracy is studied in various quantum systems through a restriction of the Feynman path-integrals around the measurement result. The method, which is equivalent to consider an effective Schr\"odinger equation with a non-Hermitian Hamiltonian, allows one to study the dynamics of the wavefunction collapse. A numerical algorithm for solving the effective Schr\"odinger equation is developed and checked in the case of a harmonic oscillator. The situations, of physical interest, of a two-level system and of a metastable quantum-well are then discussed. In the first case the Zeno inhibition observed in quantum optics experiments is recovered and extended to nonresonant transitions, in the second one we propose to observe inhibition of spontaneous decay in mesoscopic heterostructures. In all the considered examples the effect of the continuous measurement of energy is a freezing of the evolution of the system proportional to the accuracy of the measurement itself.Comment: 20 pages with figures, compressed and uuencoded ps fil

    Influence of the detector's temperature on the quantum Zeno effect

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    In this paper we study the quantum Zeno effect using the irreversible model of the measurement. The detector is modeled as a harmonic oscillator interacting with the environment. The oscillator is subjected to the force, proportional to the energy of the measured system. We use the Lindblad-type master equation to model the interaction with the environment. The influence of the detector's temperature on the quantum Zeno effect is obtained. It is shown that the quantum Zeno effect becomes stronger (the jump probability decreases) when the detector's temperature increases

    Mobilisation of Public Support for Policy Actions to Prevent Obesity

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    Public mobilisation is needed to enact obesity prevention policies and to mitigate backlash against their implementation. However, current approaches in public health focus primarily on dialogue between public health professionals and political leaders. Strategies to increase popular demand for obesity prevention policies include refining and streamlining public information, identifying effective frames for each population, enhancing media advocacy, building citizen protest and engagement, and developing a receptive political environment with change agents embedded across organisations and sectors. Long-term support and investment in collaboration among diverse stakeholders to create shared value is also important. Each actor in an expanded coalition for obesity prevention can make specific contributions to engaging, mobilising and coalescing the public. Shifting from a top-down to an integrated bottom-up and top-down approach would require an overhaul of current strategies and re-prioritisation of resources
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