2,095 research outputs found

    Single-photon optomechanics in the strong coupling regime

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    We give a theoretical description of a coherently driven opto-mechanical system with a single added photon. The photon source is modeled as a cavity which initially contains one photon and which is irreversibly coupled to the opto-mechanical system. We show that the probability for the additional photon to be emitted by the opto-mechanical cavity will exhibit oscillations under a Lorentzian envelope, when the driven interaction with the mechanical resonator is strong enough. Our scheme provides a feasible route towards quantum state transfer between optical photons and micromechanical resonators.Comment: 14 pages, 6 figure

    Overcoming detection loss and noise in squeezing-based optical sensing

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    Among the known resources of quantum metrology, one of the most practical and efficient is squeezing. Squeezed states of atoms and light improve the sensing of the phase, magnetic field, polarization, mechanical displacement. They promise to considerably increase signal-to-noise ratio in imaging and spectroscopy, and are already used in real-life gravitational-wave detectors. But despite being more robust than other states, they are still very fragile, which narrows the scope of their application. In particular, squeezed states are useless in measurements where the detection is inefficient or the noise is high. Here, we experimentally demonstrate a remedy against loss and noise: strong noiseless amplification before detection. This way, we achieve loss-tolerant operation of an interferometer fed with squeezed and coherent light. With only 50% detection efficiency and with noise exceeding the level of squeezed light more than 50 times, we overcome the shot-noise limit by 6 dB. Sub-shot-noise phase sensitivity survives up to 87% loss. Application of this technique to other types of optical sensing and imaging promises a full use of quantum resources in these fields

    The effect of applying pressure to the LIV3 and LI4 on the symptoms of premenstrual syndrome: a randomized clinical trial

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    Objective: To evaluate the effect of simple acupressure protocol in LIV3, LI4 and placebo points on the quality of life (QOL) in women with premenstrual syndrome (PMS). Method: This paper reports a randomized, single blinded clinical trial. 97 participants (students in of Hormozgan University of Medical Sciences, Iran) with PMS were allocated to three groups to receive 20 minutes acupressure on different acupoints for 14 days before menstruation for three consecutive menstrual cycles (training and then two cycles self applied acupressure).The acupoints were LIV3 and LI4; one group received acupressure at a placebo point. Each participant completed the PSST scale (to determine PMS severity), HADS scale (for depression and anxiety), and quality of life SF12. Results: The number of people with moderate/severe PMS decreased in LIV3 and LI4 acupressure groups by the second and third cycles compared with the placebo group (p<0.04). Moreover, depression and anxiety scores significantly decreased in the LIV3 and LI4 groups by the second and third cycles compared with the placebo group (p<0.05).Analyzing the score of SF12 fields in the second and third cycles showed a significant difference in all dimensions between the intervention and placebo groups. There was no significant difference between LIV3 and LI4 acupressure groups in decrease of PMS symptoms, anxiety and depression and improving SF12scores (p<0.05). Conclusion: Performing the simple acupressure protocol at LIV3 and LI4 is an effective method to decrease the severity of PMS symptoms, anxiety and depression, and to improve the QOL. Pressure at LIV3 and LI4 appear to be equally effective

    Enhanced Trabeculectomy: The Moorfields Safer Surgery System

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    Trabeculectomy with antifibrotic treatment is still the most popular incisional procedure for glaucoma filtration surgery (GFS) worldwide. The advent of antifibrotic agents reduced failure due to scarring but resulted in increased complications. Advances in trabeculectomy surgery have been driven by the need to minimise the risk of: (1) complications and (2) surgical failure. This chapter covers preoperative, intraoperative, and postoperative strategies, which improve the outcome of GFS. Strategies to reduce the risk of complications centre on the prevention of postoperative hypotony by minimising the risk of overdrainage, postoperative wound leaks, and poor bleb morphology. Surgical techniques to reduce the risk of postoperative fibrosis by the use of antifibrotic agents (including mitomycin C) are discussed in detail. These techniques are based on a combination of considerable clinical experience, observation, and laboratory research. The need to address pre-, intra-, and postoperative issues in each individual patient is emphasised. These changes are embodied in the system we call the "Moorfields Safer Surgery System." The use of these strategies has considerably reduced the incidence of major complications, including hypotony, cystic blebs, and endophthalmitis in practices around the world. Most of these techniques are simple, require minimal equipment, and can be easily mastered. They are associated with an improvement in overall outcome and it is hoped that this chapter will help the reader benefit from these advances

    Personality Traits of Mentally Disordered Males Who Committed Homicide

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    Background: The relationship between personality traits and criminal behavior has not been sufficiently investigated. This study was done to determine the personality traits in a group of criminals who have committed homicide.Methods: This study was conducted to compare the personality traits in three groups of people in Tehran during 2014. The statistical population was examined 3 communities; first, forensic psychiatric patients; Second, people who accused homicide without psychiatric diagnosis; and, matched group (with no diagnosis and crime). The study sample included 121 males; they have been divided into 3 groups: psychiatric patients who have committed homicide (n=41), murderers without any major psychiatric disorder (n=40) and control group which includes non-committed and non-patient (n=40). The cases were evaluated by a short form of Neo questionnaire.Results: There was a significant difference between the groups in terms of personality traits, which included neurosis, extroversion, agreeableness and conscientiousness. The most significant difference was in extroversion and conscientiousness variables. Psychiatric patients’ committed homicide showed higher scores than those of non-patient and the control group. Psychiatric patients had lower scores in extroversion, agreeableness and conscientiousness characteristics in comparison with the other two groups.Conclusion: Psychiatric patients who have committed homicide have more Irascible traits. Non-patient cases who committed homicide have a tendency to introspection and egocentrism and they are socially compatible in comparison with patient groups. These subjects are among dispassionate ones. The results of this study failed to demonstrate a significant difference between non-patient cases who have committed homicide and the control group

    Probing the Structure of Halo Nuclei

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    Our understanding of halo nuclei has so far relied on high-energy scattering and reactions, but a number of uncertainties remain. I discuss in general terms the new range of observables which will be measured by experiments around the Coulomb barrier, and how some details of the reaction mechanisms still need to be clarified.Comment: Proceedings of FUSION97 conference (March 1997), South Durras, Australia. Submitted to J. Physics G: special issue `Heavy ion collisions at near barrier energies'. No figures; uses IOPConf.sty (included

    Effect of different levels of Azolla meal on growth performance and digestibility of common carp (Cyprinus carpio)

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    In this study, the effects of different dietary levels of Azolla meal were investigated on growth performance and digestibility of common carp (Cyprinus carpio) fingerlings during 60 days. Five experimental diets approximately iso-protein (30%) and isolipidic (10%), were formulated with different levels of Azolla meal consisting of 0, 15, 25, 35 and 45%, respectively. In each experimental treatment, triplicate groups of common Carp fingerlings (16.5± 0.2 g) were used in a completely randomized design. Twenty fish were assigned to each experimental unit and stocked in 300 L tank. The results showed that the use of Azolla meal up to 15% had no negative effect on growth performance. The growth of fish was reduced significantly with increasing Azolla meal level of more than 15% of diet. Based on results, the apparent digestibility coefficients (ADC) of dry matter decreased with increasing Azolla meal in diets. The highest ADC of protein was observed in control treatment. However, no significant difference was observed between the treatment 2 (diet with 15% Azolla meal) and control (without Azolla meal) for ADC of protein. In general, results of the present study showed that Azolla meal can be used up to 15% in Cyprinus carpio diet

    Probing halo nucleus structure through intermediate energy elastic scattering

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    This work addresses the question of precisely what features of few body models of halo nuclei are probed by elastic scattering on protons at high centre-of-mass energies. Our treatment is based on a multiple scattering expansion of the proton-projectile transition amplitude in a form which is well adapted to the weakly bound cluster picture of halo nuclei. In the specific case of 11^{11}Li scattering from protons at 800 MeV/u we show that because core recoil effects are significant, scattering crosssections can not, in general, be deduced from knowledge of the total matter density alone. We advocate that the optical potential concept for the scattering of halo nuclei on protons should be avoided and that the multiple scattering series for the full transition amplitude should be used instead.Comment: 8 pages REVTeX, 1 eps figure, accepted for publication in Phys. Rev.
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