63 research outputs found

    Quantum Control of the Hyperfine Spin of a Cs Atom Ensemble

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    We demonstrate quantum control of a large spin-angular momentum associated with the F=3 hyperfine ground state of 133Cs. A combination of time dependent magnetic fields and a static tensor light shift is used to implement near-optimal controls and map a fiducial state to a broad range of target states, with yields in the range 0.8-0.9. Squeezed states are produced also by an adiabatic scheme that is more robust against errors. Universal control facilitates the encoding and manipulation of qubits and qudits in atomic ground states, and may lead to improvement of some precision measurements.Comment: 4 pages, 4 figures (color

    Minimal Informationally Complete Measurements for Pure States

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    We consider measurements, described by a positive-operator-valued measure (POVM), whose outcome probabilities determine an arbitrary pure state of a D-dimensional quantum system. We call such a measurement a pure-state informationally complete (PSI-complete) POVM. We show that a measurement with 2D-1 outcomes cannot be PSI-complete, and then we construct a POVM with 2D outcomes that suffices, thus showing that a minimal PSI-complete POVM has 2D outcomes. We also consider PSI-complete POVMs that have only rank-one POVM elements and construct an example with 3D-2 outcomes, which is a generalization of the tetrahedral measurement for a qubit. The question of the minimal number of elements in a rank-one PSI-complete POVM is left open.Comment: 2 figures, submitted for the Asher Peres festschrif

    Effects of a 105 hours psychological training program on attitudes, communication skills and occupational stress in oncology: a randomised study

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    There is today a wide consensus regarding the need to improve communication skills (CS) of health-care professionals (HCPs) dealing with cancer patients. Psychological training programs (PTPs) may be useful to acquire the needed CS. Testing the efficacy of PTP will allow to define their optimal content. The present study was designed to assess the impact of a PTP on HCP stress, attitudes and CS, and on HCP and patients' satisfaction with HCP communication skills in a randomised study. A total of 115 oncology nurses were randomly assigned to a 105-h PTP or to a waiting list. Stress was assessed with the Nursing Stress Scale, attitudes with a Semantic Differential Questionnaire, CS used during one simulated and one actual patient interview with the Cancer Research Campaign Workshop Evaluation Manual, and satisfaction with the nurses' CS with a questionnaire completed by the patients and the nurses. Trained (TG) and control (CG) groups were compared at baseline, after 3 months (just following training for TG) and after 6 months (3 months after the end of training for TG). Compared to controls, trained nurses reported positive changes on their stress levels (P</=0.05) and on their attitudes (P</=0.05). Positive training effects were found on CS used during the simulated interview: a significant increase in facilitative behaviours (open questions: P</=0.001; evaluative functions: P</=0.05) and a significant decrease in inhibitory behaviours (inappropriate information: P</=0.01; false reassurance: P</=0.05). Less positive training effects were found regarding interviews with a cancer patient: a significant increase in educated guesses (P</=0.001) was noticed. No training effect was observed on nurses' satisfaction levels, but a positive training effect was found on patients' satisfaction levels (P</=0.01). Although results outline PTP efficacy, they indicate the need to design PTP, amplifying the transfer of learned CS to clinical practice.info:eu-repo/semantics/publishe

    Distribution and determinants of patient satisfaction in oncology with a focus on health related quality of life

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    <p>Abstract</p> <p>Background</p> <p>Cancer patients usually undergo extensive and debilitating treatments, which make quality of life (QoL) and patient satisfaction important health care assessment measures. However, very few studies have evaluated the relationship between QoL and patient satisfaction in oncology. We investigated the clinical, demographic and QoL factors associated with patient satisfaction in a large heterogeneous sample of cancer patients.</p> <p>Methods</p> <p>A cohort of 538 cancer patients treated at Cancer Treatment Centers of America<sup>® </sup>(CTCA) was assessed. A patient satisfaction questionnaire developed in-house by CTCA was used. It covered the following dimensions of patient satisfaction: hospital operations and services, physicians and staff, and patient endorsements for themselves and others. QoL was assessed using the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30). The clinical, demographic and QoL factors were evaluated for predictive significance using univariate and multivariate logistic regression.</p> <p>Results</p> <p>The mean age of our patient population was 54.1 years (SD = 10.5, range 17-86), with a slight preponderance of females (57.2%). Breast cancer (n = 124) and lung cancer (n = 101) were the most frequent cancer types. 481 (89.4%) patients were "very satisfied" with their overall experience. Age and several QoL function and symptom scales were predictive of overall patient satisfaction upon univariate analysis. In the multivariate modeling, only those with a score above the median on the fatigue measure (i.e. worse fatigue) had reduced odds of 0.28 of being very satisfied (p = 0.03).</p> <p>Conclusion</p> <p>Patient fatigue, as reported by the QoL fatigue scale, was an independent significant predictor of overall patient satisfaction. This finding argues for special attention and programs for cancer patients who report higher levels of fatigue given that fatigue is the most frequently reported symptom in cancer patients.</p

    Circadian function in patients with advanced non-small-cell lung cancer

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    This study aimed to evaluate whether patients with advanced non-small-cell lung cancer experience disrupted rest–activity daily rhythms, poor sleep quality, weakness, and maintain attributes that are linked to circadian function such as fatigue. This report describes the rest–activity patterns of 33 non-small-cell lung cancer patients who participated in a randomised clinical trial evaluating the benefits of melatonin. Data are reported on circadian function, health-related quality of life (QoL), subjective sleep quality, and anxiety/depression levels prior to randomisation and treatment. Actigraphy data, an objective measure of circadian function, demonstrated that patients' rest–activity circadian function differs significantly from control subjects. Our patients reported poor sleep quality and high levels of fatigue. Ferrans and Powers QoL Index instrument found a high level of dissatisfaction with health-related QoL. Data from the European Organization for Research and Treatment for Cancer reported poor capacity to fulfil the activities of daily living. Patients studied in the hospital during or near chemotherapy had significantly more abnormal circadian function than those studied in the ambulatory setting. Our data indicate that measurement of circadian sleep/activity dynamics should be accomplished in the outpatient/home setting for a minimum of 4–7 circadian cycles to assure that they are most representative of the patients' true condition. We conclude that the daily sleep/activity patterns of patients with advanced lung cancer are disturbed. These are accompanied by marked disruption of QoL and function. These data argue for investigating how much of this poor functioning and QoL are actually caused by this circadian disruption, and, whether behavioural, light-based, and or pharmacologic strategies to correct the circadian/sleep activity patterns can improve function and QoL

    Photon-Atom Coupling with Parabolic Mirrors

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    Efficient coupling of light to single atomic systems has gained considerable attention over the past decades. This development is driven by the continuous growth of quantum technologies. The efficient coupling of light and matter is an enabling technology for quantum information processing and quantum communication. And indeed, in recent years much progress has been made in this direction. But applications aside, the interaction of photons and atoms is a fundamental physics problem. There are various possibilities for making this interaction more efficient, among them the apparently 'natural' attempt of mode-matching the light field to the free-space emission pattern of the atomic system of interest. Here we will describe the necessary steps of implementing this mode-matching with the ultimate aim of reaching unit coupling efficiency. We describe the use of deep parabolic mirrors as the central optical element of a free-space coupling scheme, covering the preparation of suitable modes of the field incident onto these mirrors as well as the location of an atom at the mirror's focus. Furthermore, we establish a robust method for determining the efficiency of the photon-atom coupling.Comment: Book chapter in compilation "Engineering the Atom-Photon Interaction" published by Springer in 2015, edited by A. Predojevic and M. W. Mitchell, ISBN 9783319192307, http://www.springer.com/gp/book/9783319192307. Only change to version1: now with hyperlinks to arXiv eprints of other book chapters mentioned in this on

    Assessment of sleep in patients with lung cancer and breast cancer.

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