351 research outputs found

    Ground State Entanglement Energetics

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    We consider the ground state of simple quantum systems coupled to an environment. In general the system is entangled with its environment. As a consequence, even at zero temperature, the energy of the system is not sharp: a projective measurement can find the system in an excited state. We show that energy fluctuation measurements at zero temperature provide entanglement information. For two-state systems which exhibit a persistent current in the ground state, energy fluctuations and persistent current fluctuations are closely related. The harmonic oscillator serves to illustrate energy fluctuations in a system with an infinite number of states. In addition to the energy distribution we discuss the energy-energy time-correlation function in the zero-temperature limit.Comment: 10 pages, 6 figure

    Aharonov-Bohm ring with fluctuating flux

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    We consider a non-interacting system of electrons on a clean one-channel Aharonov-Bohm ring which is threaded by a fluctuating magnetic flux. The flux derives from a Caldeira-Leggett bath of harmonic oscillators. We address the influence of the bath on the following properties: one- and two-particle Green's functions, dephasing, persistent current and visibility of the Aharonov-Bohm effect in cotunneling transport through the ring. For the bath spectra considered here (including Nyquist noise of an external coil), we find no dephasing in the linear transport regime at zero temperature. PACS numbers: 73.23.-b, 73.23.Hk, 73.23.Ra, 03.65.YzComment: 17 pages, 8 figures. To be published in PRB. New version contains minor corrections and additional discussion suggested by referee. A simple introduction to the basics of dephasing can be found at http://iff.physik.unibas.ch/~florian/dephasing/dephasing.htm

    Characteristics of elderly patients with fibromyalgia: a pilot retrospective study

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    Background and aims: Very little informations are available about the characteristics of fibromyalgia (FM) in older patients. The objective of the study was to know better what are some of their specificities in order to tailor the management of elderly patients with FM. Methods: Retrospective chart review of all patients with a diagnosis of FM addressed to the pain consultation of a geriatric hospital, have been analysed. Results: Forty patients (38 women and 2 men) were included. Mean age at the moment of diagnosis of FM was 75±9.1 years. Patients were hospitalized with a mean of 6±5.2 years after onset of FM. Median pain intensity measured by a visual or numerical pain scale was 6 at rest and 9 during mobilisation. Seventeen patients were isolated at home because of pain. Symptoms associated with FM were depression (n=25), fatigue and poor sleep quality (n=24), anxiety (n=15), irritable bowel syndrome (n=10), restless leg syndrome (n=3) and tension-type headache (n=2). Traumatic events, such as the death of a relative or nursing home admission were frequent. Twenty-four patients were discharged home, 13 patients in a nursing home and 3 patients died during the hospitalisation. Discussion: Although elderly patients with FM constituted a small proportion of elderly patient's addressed to a pain consultation, these patients have some particular features that must be taken into account. Further prospective studies should be conducted in this populatio

    Persistent current noise and electron-electron interactions

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    We analyze fluctuations of persistent current (PC) produced by a charged quantum particle moving in a ring and interacting with a dissipative environment formed by diffusive electron gas. We demonstrate that in the presence of interactions such PC fluctuations persist down to zero temperature. In the case of weak interactions and/or sufficiently small values of the ring radius RR PC noise remains coherent and can be tuned by external magnetic flux Φx\Phi_x piercing the ring. In the opposite limit of strong interactions and/or large values of RR fluctuations in the electronic bath strongly suppress quantum coherence of the particle down to T=0T=0 and induce incoherent Φx\Phi_x-independent current noise in the ring which persists even at Φx=0\Phi_x=0 when the average PC is absent.Comment: 12 pages, 8 figure

    EuroSpine Task Force on Research: support for spine researchers

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    In recognition of the value of research to the practice of spine care, Federico Balagué and Ferran Pellisé, at the time President and Secretary for EuroSpine, asked Margareta Nordin to set up a Task Force on Research (TFR) for EuroSpine during summer 2011. The concept was to stimulate and facilitate a research community within the society, through two main functions: (1) distribution of EuroSpine funds to researchers; (2) develop and deliver research training/education courses. What has the EuroSpine TFR accomplished since its inception

    The representation of the back in idiomatic expressions--do idioms value the body?

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    Objective: Whilst investigating the influence of patients' representations on the impact of teaching in the back school, we took an interest in 1) the place of the back in the French idioms referring to the body; and 2) the meaning these idioms convey about the back. Methods: The idioms including body part terms were sought on the basis of a compilation of French idioms; it has to be noted that such a compilation, however excellent it may be, can only offer a partial view of lay conversation. Occurrence of body parts and of their connotations were assessed. Idioms were classified as positive, negative or neutral, keeping in mind the difficulties of a strict classification in such a field. Drawings were then performed on the basis of the results of the descriptive analysis. Results: Globally, idiomatic expressions offer a rather negative picture of the body or at least suggest that the body is prominently used to express negative ideas and emotions. This is particularly striking for the idioms associated with the back. Conclusion: The analysis of idioms referring to the body allows us to 'see with our own eyes' another aspect of the representations of the body and the back, as they are conveyed in the French language. [Authors]]]> Back ; Communication Barriers ; Health Knowledge, Attitudes, Practice ; Semantics oai:serval.unil.ch:BIB_136ABBE1E5F6 2022-05-07T01:10:42Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_136ABBE1E5F6 Alessandro Tassoni Bucchi, Gabriele info:eu-repo/semantics/bookPart incollection 2022-04-01 Autografi dei letterati italiani. Il Cinquecento, vol. III, A cura di Matteo Motolese, Paolo Procaccioli, Emilio Russo,, pp. 417-434 ita oai:serval.unil.ch:BIB_136B34CCEB93 2022-05-07T01:10:42Z openaire documents urnserval <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_136B34CCEB93 Témoigner avant et après la guérison. Ce que le témoignage fait à la communauté. http://www.erudit.org/revue/ethno/ Monnot, C. Gonzalez, P. info:eu-repo/semantics/article article 2011 Ethnologies, vol. 33, no. 1, pp. 95-116 <![CDATA[Trois ans après avoir témoigné de son mal chronique, une fidèle s'exprime à nouveau devant sa communauté, une Église évangélique de type charismatique. Elle partage la nouvelle de sa guérison miraculeuse. L'analyse comparée de ces récits, ainsi qu'une description ethnographique des célébrations durant lesquelles ils sont émis, montre comment l'énonciation de la croyante est encadrée par le pasteur. Une approche pragmatique et énonciative permet de ressaisir simultanément cet encadrement au plan institutionnel et interactionnel. On verra alors comment cette parole publique contribue à redéfinir la perception que la communauté a de Dieu et d'elle-même. Chacune des situations de témoignage renvoie ainsi à deux façons présentes au sein de l'évangélisme charismatique de se rapporter au surnaturel qui ont un impact sur l'organisation des Églises locales.Three years after sharing publicly about her chronic illness, a believer addresses again her congregation, an Evangelical church with Charismatic leanings. She shares the news of her miraculous healing. A comparative analysis of those testimonies and on ethnographic descriptions of the worship services during which she spoke will show how the pastor frames the believer's enunciation. A pragmatic and enunciative approach recaptures simultaneously both interactional and institutional levels. It will appear that the public speech contributes to redefining the congregation's perception of God and of itself. Both testimony settings show two ways, within Charismatic Evangelism, to refer to the supernatural. Those ways have an impact on the organization of the local churches

    Zero-Point Fluctuations and the Quenching of the Persistent Current in Normal Metal Rings

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    The ground state of a phase-coherent mesoscopic system is sensitive to its environment. We investigate the persistent current of a ring with a quantum dot which is capacitively coupled to an external circuit with a dissipative impedance. At zero temperature, zero-point quantum fluctuations lead to a strong suppression of the persistent current with decreasing external impedance. We emphasize the role of displacement currents in the dynamical fluctuations of the persistent current and show that with decreasing external impedance the fluctuations exceed the average persistent current.Comment: 4 pages, 2 eps figure

    Exploring the major difficulties perceived by residents in training: a pilot study.

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    To assess residents' difficulties during the first year of residency. In contrast to previous studies that mainly used structured questionnaires, a qualitative procedure was applied. Twenty-four consecutive first-year residents in internal medicine were asked to "Please identify two to three major difficulties or concerns related to your practice of medicine within this hospital". The answers were submitted to content analysis performed by three independent researchers. Inter-rater agreement was high (kappa coefficient = 0.92). Disagreements were solved by consensus. Physicians' characteristics: female 37%, mean age 28 +/- 2.2 years, mean duration of postgraduate training 2.5 +/- 1.3 years. Total number of answers: 122, average answers/resident 5.1 +/- 1.3. Nine categories were extracted from content analysis: communication problems at the workplace, feelings of not being respected, constraints of collaborative work, experiencing the gap between medical school and clinical care, work overload, responsibility towards and emotional investment in patients, worries about career plans, and lack of theoretical knowledge. Residents expressed major difficulties in communicating with and being respected by seniors and peers in particular, and hospital staff in general. They also voiced problems in coping with emotions, either their own or those of their patients. The residents' responses stressed the complexity of blending the requirements of the physician's role when instrumental/cognitive knowledge is not sufficient to deal with problems requiring personal and relational dimensions. Learning to combine medical knowledge and practice necessitates helping students/residents identify and deal with the constraints of these requirements

    Zero-point fluctuations in the ground state of a mesoscopic normal ring

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    We investigate the persistent current of a ring with an in-line quantum dot capacitively coupled to an external circuit. Of special interest is the magnitude of the persistent current as a function of the external impedance in the zero temperature limit when the only fluctuations in the external circuit are zero-point fluctuations. These are time-dependent fluctuations which polarize the ring-dot structure and we discuss in detail the contribution of displacement currents to the persistent current. We have earlier discussed an exact solution for the persistent current and its fluctuations based on a Bethe ansatz. In this work, we emphasize a physically more intuitive approach using a Langevin description of the external circuit. This approach is limited to weak coupling between the ring and the external circuit. We show that the zero temperature persistent current obtained in this approach is consistent with the persistent current calculated from a Bethe ansatz solution. In the absence of coupling our system is a two level system consisting of the ground state and the first excited state. In the presence of coupling we investigate the projection of the actual state on the ground state and the first exited state of the decoupled ring. With each of these projections we can associate a phase diffusion time. In the zero temperature limit we find that the phase diffusion time of the excited state projection saturates, whereas the phase diffusion time of the ground state projection diverges.Comment: 12 pages, 5 figure

    Dephasing in sequential tunneling through a double-dot interferometer

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    We analyze dephasing in a model system where electrons tunnel sequentially through a symmetric interference setup consisting of two single-level quantum dots. Depending on the phase difference between the two tunneling paths, this may result in perfect destructive interference. However, if the dots are coupled to a bath, it may act as a which-way detector, leading to partial suppression of the phase-coherence and the reappearance of a finite tunneling current. In our approach, the tunneling is treated in leading order whereas coupling to the bath is kept to all orders (using P(E) theory). We discuss the influence of different bath spectra on the visibility of the interference pattern, including the distinction between "mere renormalization effects" and "true dephasing".Comment: 18 pages, 8 figures; For a tutorial introduction to dephasing see http://iff.physik.unibas.ch/~florian/dephasing/dephasing.htm
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