1,354 research outputs found

    Rare quantum metastable states in the strongly dispersive Jaynes-Cummings oscillator

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    We present evidence of metastable rare quantum-fluctuation switching for the driven dissipative Jaynes-Cummings oscillator coupled to a zero-temperature bath in the strongly dispersive regime. We show that single-atom complex amplitude bistability is accompanied by the appearance of a low-amplitude long-lived transient state, hereinafter called `dark state', having a distribution with quasi-Poissonian statistics both for the coupled qubit and cavity mode. We find that the dark state is linked to a spontaneous flipping of the qubit state, detuning the cavity to a low-photon response. The appearance of the dark state is correlated with the participation of the two metastable states in the dispersive bistability, as evidenced by the solution of the Master Equation and single quantum trajectories.Comment: Extensively revised text, 18 revised figures (16 in main and 2 in appendix), 38(+1) references, appendi

    Parallel quantum simulation of large systems on small NISQ computers

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    Tensor networks permit computational and entanglement resources to be concentrated in interesting regions of Hilbert space. Implemented on NISQ machines they allow simulation of quantum systems that are much larger than the computational machine itself. This is achieved by parallelising the quantum simulation. Here, we demonstrate this in the simplest case; an infinite, translationally invariant quantum spin chain. We provide Cirq and Qiskit code that translates infinite, translationally invariant matrix product state (iMPS) algorithms to finite-depth quantum circuit machines, allowing the representation, optimisation and evolution of arbitrary one-dimensional systems. The illustrative simulated output of these codes for achievable circuit sizes is given

    Fatigue in celiac disease: A review of the literature

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    Fatigue is increasingly recognized as a significant problem in patients with chronic inflammatory and autoimmune diseases. In celiac disease, a chronic immune‐mediated disease triggered by dietary gluten, conflicting opinions exist regarding both the size of the problem and the effect of a gluten‐free diet (GFD) on fatigue. We reviewed the existing literature regarding fatigue in celiac disease. We conducted a systematic search in the Embase, Ovid Medline, and Cochrane databases using subject terms from controlled vocabularies. Articles were reviewed based on language, type of article, title, and abstract or full text. Eighteen articles were finally selected for review. Fatigue was significantly greater in patients with celiac disease compared to healthy control subjects. Fatigue prevalence ranged from 8 to 100%. Fatigue severity was assessed in six studies. The fatigue visual analogue scale was the most frequently used fatigue instrument with scores from 57 to 79 prior to starting a GFD and from 39 to 59 in patients on a GFD. Seven studies investigated the effect of a GFD on fatigue, including five studies that reported less fatigue while on the diet and two studies that showed no significant difference. This review concludes that fatigue is a substantial complaint in patients with celiac disease. A GFD seems to reduce fatigue, but existing data are limited.publishedVersio

    C Wright Mills, power and the power elites ? a reappraisal

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    This paper revisits and presents a critical appraisal of Mills's analysis of power and the power elite. There are signs of a revival of interest in Mills, but recent commentators have shown little interest in the intellectual, social or political context of his analysis. Setting Mills's thesis in its historical context, we consider an element of his project that has been particularly neglected in recent discussion: Mills's search for possible ways of redistributing power and his attempt to forge an ethico-political stance. Reflecting on recent discussion of contemporary elite formations, we comment on what critics might take from Mills in our own time in relation to the analysis of elites and the politics of critical management studies

    Rayleigh-B\'{e}nard convection in a homeotropically aligned nematic liquid crystal

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    We report experimental results for convection near onset in a thin layer of a homeotropically aligned nematic liquid crystal heated from below as a function of the temperature difference ΔT\Delta T and the applied vertical magnetic field HH and compare them with theoretical calculations. The experiments cover the field range 8 \alt h \equiv H/ H_{F} \alt 80 (HF=H_F = is the Fr\'eedericksz field). For hh less than a codimension-two field hct46h_{ct} \simeq 46 the bifurcation is subcritical and oscillatory, with travelling- and standing-wave transients. Beyond hcth_{ct} the bifurcation is stationary and subcritical until a tricritical field ht=57.2h_t= 57.2 is reached, beyond which it is supercritical. The bifurcation sequence as a function of hh found in the experiment confirms the qualitative aspects of the theoretical predictions. However, the value of hcth_{ct} is about 10% higher than the predicted value and the results for kck_c are systematically below the theory by about 2% at small hh and by as much as 7% near hcth_{ct}. At hcth_{ct}, kck_c is continuous within the experimental resolution whereas the theory indicates a 7% discontinuity. The theoretical tricritical field htth=51h_t^{th} = 51 is somewhat below the experimental one. The fully developed flow above RcR_c for h<hcth < h_{ct} is chaotic. For hct<h<hth_{ct} < h < h_t the subcritical stationary bifurcation also leads to a chaotic state. The chaotic states persist upon reducing the Rayleigh number below RcR_c, i.e. the bifurcation is hysteretic. Above the tricritical field hth_t, we find a bifurcation to a time independent pattern which within our resolution is non-hysteretic.Comment: 15 pages incl. 23 eps figure

    A New Approach toward Transition State Spectroscopy

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    Chirped-Pulse millimetre-Wave (CPmmW) rotational spectroscopy provides a new class of information about photolysis transition state(s). Measured intensities in rotational spectra determine species-isomer-vibrational populations, provided that rotational populations can be thermalized. The formation and detection of S0 vinylidene is discussed in the limits of low and high initial rotational excitation. CPmmW spectra of 193 nm photolysis of Vinyl Cyanide (Acrylonitrile) contain J=0-1 transitions in more than 20 vibrational levels of HCN, HNC, but no transitions in vinylidene or highly excited local-bender vibrational levels of acetylene. Reasons for the non-observation of the vinylidene co-product of HCN are discussed.Comment: Accepted by Faraday Discussion

    Results of an international drug testing service for cryptomarket users

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    Introduction: User surveys indicate that expectations of higher drug purity are a key reason for cryptomarket use. In 2014-2015, Spain's NGO Energy Control conducted a 1-year pilot project to provide a testing service to cryptomarket drug users using the Transnational European Drug Information (TEDI) guidelines. In this paper, we present content and purity data from the trial. Methods: 219 samples were analyzed by gas chromatography associated with mass spectrometry (GC/MS). Users were asked to report what substance they allegedly purchased. Results: 40 different advertised substances were reported, although 77.6% were common recreational drugs (cocaine, MDMA, amphetamines, LSD, ketamine, cannabis). In 200 samples (91.3%), the main result of analysis matched the advertised substance. Where the advertised compound was detected, purity levels (m. ±. SD) were: cocaine 71.6. ±. 19.4%; MDMA (crystal) 88.3. ±. 1.4%; MDMA (pills) 133.3. ±. 38.4. mg; Amphetamine (speed) 51.3. ±. 33.9%; LSD 123.6. ±. 40.5. µg; Cannabis resin THC: 16.5. ±. 7.5% CBD: 3.4. ±. 1.5%; Ketamine 71.3. ±. 38.4%. 39.8% of cocaine samples contained the adulterant levamisole (11.6. ±. 8%). No adulterants were found in MDMA and LSD samples. Discussion: The largest collection of test results from drug samples delivered from cryptomarkets are reported in this study. Most substances contained the advertised ingredient and most samples were of high purity. The representativeness of these results is unknown

    Smash products for secondary homotopy groups

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    We construct a smash product operation on secondary homotopy groups yielding the structure of a lax symmetric monoidal functor. Applications on cup-one products, Toda brackets and Whitehead products are considered. In particular we prove a formula for the crossed effect of the cup-one product operation on unstable homotopy groups of spheres which was claimed by Barratt-Jones-Mahowald.Comment: We give a clearer description of the tensor product of symmetric sequences of quadratic pair module

    The Spheres & Shield Maze Task: A virtual reality serious game for the assessment of risk taking in decision making

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    [EN] Risk taking (RT) is an essential component in decision-making process that depicts the propensity to make risky decisions. RT assessment has traditionally focused on self-report questionnaires. These classical tools have shown clear distance from real-life responses. Behavioral tasks assess human behavior with more fidelity, but still show some limitations related to transferability. A way to overcome these constraints is to take advantage from virtual reality (VR), to recreate real-simulated situations that might arise from performance-based assessments, supporting RT research. This article presents results of a pilot study in which 41 individuals explored a gamified VR environment: the Spheres & Shield Maze Task (SSMT). By eliciting implicit behavioral measures, we found relationships between scores obtained in the SSMT and self-reported risk-related constructs, as engagement in risky behaviors and marijuana consumption. We conclude that decontextualized Virtual Reality Serious Games are appropriate to assess RT, since they could be used as a cross-disciplinary tool to assess individuals' capabilities under the stealth assessment paradigm.This work was supported by the Spanish Ministry of Economy, Industry and Competitiveness funded projects "Advanced Therapeutic Tools for Mental Health'' (DPI2016-77396-R), and "Assessment and Training on Decision Making in Risk Environments'' (RTC-2017-6523-6) (MINECO/AEI/FEDER,UE) and by the Generalitat Valenciana funded project "Rebrand'' (PROMETEU/2019/105).Juan-Ripoll, CD.; Soler-Domínguez, JL.; Chicchi-Giglioli, IA.; Contero, M.; Alcañiz Raya, ML. (2020). The Spheres & Shield Maze Task: A virtual reality serious game for the assessment of risk taking in decision making. Cyberpsychology Behavior and Social Networking. 23(11):773-781. https://doi.org/10.1089/cyber.2019.0761S7737812311Bechara, A., Damasio, H., Tranel, D., & Damasio, A. R. (2005). The Iowa Gambling Task and the somatic marker hypothesis: some questions and answers. Trends in Cognitive Sciences, 9(4), 159-162. doi:10.1016/j.tics.2005.02.002Krain, A. L., Wilson, A. M., Arbuckle, R., Castellanos, F. X., & Milham, M. P. (2006). Distinct neural mechanisms of risk and ambiguity: A meta-analysis of decision-making. NeuroImage, 32(1), 477-484. doi:10.1016/j.neuroimage.2006.02.047Einhorn, H. J. (1970). The use of nonlinear, noncompensatory models in decision making. Psychological Bulletin, 73(3), 221-230. doi:10.1037/h0028695Figner, B., & Weber, E. U. (2011). Who Takes Risks When and Why? Current Directions in Psychological Science, 20(4), 211-216. doi:10.1177/0963721411415790Endsley, M. R., & Garland, D. J. (Eds.). (2000). Situation Awareness Analysis and Measurement. doi:10.1201/b12461Lauriola, M., & Levin, I. P. (2001). Personality traits and risky decision-making in a controlled experimental task: an exploratory study. Personality and Individual Differences, 31(2), 215-226. doi:10.1016/s0191-8869(00)00130-6Rundmo, T. (1996). Associations between risk perception and safety. Safety Science, 24(3), 197-209. doi:10.1016/s0925-7535(97)00038-6Zuckerman, M., & Kuhlman, D. M. (2000). Personality and Risk‐Taking: Common Bisocial Factors. Journal of Personality, 68(6), 999-1029. doi:10.1111/1467-6494.00124Dahlen, E. R., Martin, R. C., Ragan, K., & Kuhlman, M. M. (2005). Driving anger, sensation seeking, impulsiveness, and boredom proneness in the prediction of unsafe driving. Accident Analysis & Prevention, 37(2), 341-348. doi:10.1016/j.aap.2004.10.006Donohew, L., Zimmerman, R., Cupp, P. S., Novak, S., Colon, S., & Abell, R. (2000). Sensation seeking, impulsive decision-making, and risky sex: implications for risk-taking and design of interventions. Personality and Individual Differences, 28(6), 1079-1091. doi:10.1016/s0191-8869(99)00158-0Moreno, M., Estevez, A. F., Zaldivar, F., Montes, J. M. G., Gutiérrez-Ferre, V. E., Esteban, L., … Flores, P. (2012). Impulsivity differences in recreational cannabis users and binge drinkers in a university population. Drug and Alcohol Dependence, 124(3), 355-362. doi:10.1016/j.drugalcdep.2012.02.011Dvorak, R. D., & Day, A. M. (2014). Marijuana and self-regulation: Examining likelihood and intensity of use and problems. Addictive Behaviors, 39(3), 709-712. doi:10.1016/j.addbeh.2013.11.001Trocki, K. F., Drabble, L. A., & Midanik, L. T. (2009). Tobacco, marijuana, and sensation seeking: Comparisons across gay, lesbian, bisexual, and heterosexual groups. Psychology of Addictive Behaviors, 23(4), 620-631. doi:10.1037/a0017334Ames, S. L., Zogg, J. B., & Stacy, A. W. (2002). Implicit cognition, sensation seeking, marijuana use and driving behavior among drug offenders. Personality and Individual Differences, 33(7), 1055-1072. doi:10.1016/s0191-8869(01)00212-4Highhouse, S., Nye, C. D., Zhang, D. C., & Rada, T. B. (2016). Structure of the Dospert: Is There Evidence for a General Risk Factor? Journal of Behavioral Decision Making, 30(2), 400-406. doi:10.1002/bdm.1953Jackson, D. N., Hourany, L., & Vidmar, N. J. (1972). A four-dimensional interpretation of risk taking1. Journal of Personality, 40(3), 483-501. doi:10.1111/j.1467-6494.1972.tb00075.xSkeel, R. L., Neudecker, J., Pilarski, C., & Pytlak, K. (2007). The utility of personality variables and behaviorally-based measures in the prediction of risk-taking behavior. Personality and Individual Differences, 43(1), 203-214. doi:10.1016/j.paid.2006.11.025Horvath, P., & Zuckerman, M. (1993). Sensation seeking, risk appraisal, and risky behavior. Personality and Individual Differences, 14(1), 41-52. doi:10.1016/0191-8869(93)90173-zLejuez, C. W., Aklin, W. M., Zvolensky, M. J., & Pedulla, C. M. (2003). Evaluation of the Balloon Analogue Risk Task (BART) as a predictor of adolescent real-world risk-taking behaviours. Journal of Adolescence, 26(4), 475-479. doi:10.1016/s0140-1971(03)00036-8Verhulst, N., De Keyser, A., Gustafsson, A., Shams, P., & Van Vaerenbergh, Y. (2019). Neuroscience in service research: an overview and discussion of its possibilities. Journal of Service Management, 30(5), 621-649. doi:10.1108/josm-05-2019-0135de-Juan-Ripoll, C., Soler-Domínguez, J. L., Guixeres, J., Contero, M., Álvarez Gutiérrez, N., & Alcañiz, M. (2018). Virtual Reality as a New Approach for Risk Taking Assessment. Frontiers in Psychology, 9. doi:10.3389/fpsyg.2018.02532Bechara, A., Damasio, A. R., Damasio, H., & Anderson, S. W. (1994). Insensitivity to future consequences following damage to human prefrontal cortex. Cognition, 50(1-3), 7-15. doi:10.1016/0010-0277(94)90018-3Bottari, C., Dassa, C., Rainville, C., & Dutil, É. (2009). The factorial validity and internal consistency of the Instrumental Activities of Daily Living Profile in individuals with a traumatic brain injury. Neuropsychological Rehabilitation, 19(2), 177-207. doi:10.1080/09602010802188435Verschoor, A., D’Exelle, B., & Perez-Viana, B. (2016). Lab and life: Does risky choice behaviour observed in experiments reflect that in the real world? Journal of Economic Behavior & Organization, 128, 134-148. doi:10.1016/j.jebo.2016.05.009Tarr, M. J., & Warren, W. H. (2002). Virtual reality in behavioral neuroscience and beyond. Nature Neuroscience, 5(S11), 1089-1092. doi:10.1038/nn948Alcañiz, M., Rey, B., Tembl, J., & Parkhutik, V. (2009). A Neuroscience Approach to Virtual Reality Experience Using Transcranial Doppler Monitoring. Presence: Teleoperators and Virtual Environments, 18(2), 97-111. doi:10.1162/pres.18.2.97Chittaro, L., & Ranon, R. (2009). Serious Games for Training Occupants of a Building in Personal Fire Safety Skills. 2009 Conference in Games and Virtual Worlds for Serious Applications. doi:10.1109/vs-games.2009.8Lovreglio, R., Gonzalez, V., Amor, R., Spearpoint, M., Thomas, J., Trotter, M., & Sacks, R. (2017). The Need for Enhancing Earthquake Evacuee Safety by Using Virtual Reality Serious Games. Lean and Computing in Construction Congress - Volume 1: Proceedings of the Joint Conference on Computing in Construction. doi:10.24928/jc3-2017/0058Rizzo, A. A., Bowerly, T., Buckwalter, J. G., Klimchuk, D., Mitura, R., & Parsons, T. D. (2009). A Virtual Reality Scenario for All Seasons:The Virtual Classroom. CNS Spectrums, 11(1), 35-44. doi:10.1017/s1092852900024196Chicchi Giglioli, I. A., de Juan Ripoll, C., Parra, E., & Alcañiz Raya, M. (2019). Are 3D virtual environments better than 2D interfaces in serious games performance? An explorative study for the assessment of executive functions. Applied Neuropsychology: Adult, 28(2), 148-157. doi:10.1080/23279095.2019.1607735Huang, H.-M., Rauch, U., & Liaw, S.-S. (2010). Investigating learners’ attitudes toward virtual reality learning environments: Based on a constructivist approach. Computers & Education, 55(3), 1171-1182. doi:10.1016/j.compedu.2010.05.014Dalgarno, B., & Lee, M. J. W. (2009). What are the learning affordances of 3-D virtual environments? British Journal of Educational Technology, 41(1), 10-32. doi:10.1111/j.1467-8535.2009.01038.xFowler, C. (2014). Virtual reality and learning: Where is the pedagogy? British Journal of Educational Technology, 46(2), 412-422. doi:10.1111/bjet.12135Zuckerman, M., Kolin, E. A., Price, L., & Zoob, I. (1964). Development of a sensation-seeking scale. Journal of Consulting Psychology, 28(6), 477-482. doi:10.1037/h0040995Patton, J. H., Stanford, M. S., & Barratt, E. S. (1995). Factor structure of the barratt impulsiveness scale. Journal of Clinical Psychology, 51(6), 768-774. doi:10.1002/1097-4679(199511)51:63.0.co;2-1So, R. H. Y., Lo, W. T., & Ho, A. T. K. (2001). Effects of Navigation Speed on Motion Sickness Caused by an Immersive Virtual Environment. Human Factors: The Journal of the Human Factors and Ergonomics Society, 43(3), 452-461. doi:10.1518/001872001775898223Zuckerman, M. (2008). Sensation Seeking. The International Encyclopedia of Communication. doi:10.1002/9781405186407.wbiecs029Orlebeke, J. F., Van Der Molen, M. W., Dolan, C., & Stoffels, E. J. (1990). The additive factor logic applied to the personality trait disinhibition. Personality and Individual Differences, 11(6), 553-558. doi:10.1016/0191-8869(90)90037-rPopham, L. E., Kennison, S. M., & Bradley, K. I. (2011). Ageism, Sensation-Seeking, and Risk-Taking Behavior in Young Adults. Current Psychology, 30(2), 184-193. doi:10.1007/s12144-011-9107-0Roberti, J. W. (2004). A review of behavioral and biological correlates of sensation seeking. Journal of Research in Personality, 38(3), 256-279. doi:10.1016/s0092-6566(03)00067-9Zuckerman, M., Eysenck, S. B., & Eysenck, H. J. (1978). Sensation seeking in England and America: Cross-cultural, age, and sex comparisons. Journal of Consulting and Clinical Psychology, 46(1), 139-149. doi:10.1037/0022-006x.46.1.139Television campaigns and adolescent marijuana use: tests of sensation seeking targeting. (2001). American Journal of Public Health, 91(2), 292-296. doi:10.2105/ajph.91.2.292Barry, D., & Petry, N. M. (2008). Predictors of decision-making on the Iowa Gambling Task: Independent effects of lifetime history of substance use disorders and performance on the Trail Making Test. Brain and Cognition, 66(3), 243-252. doi:10.1016/j.bandc.2007.09.00
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