1,408 research outputs found

    Externalizing psychopatholog yand the error-related negativity

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    Prior research has demonstrated that antisocial behavior, substance-use disorders, and personality dimensions of aggression and impulsivity are indicators of a highly heritable underlying dimension of risk, labeled externalizing. Other work has shown that individual trait constructs within this psychopathology spectrum are associated with reduced self-monitoring, as reflected by amplitude of the error-related negativity (ERN) brain response. In this study of undergraduate subjects, reduced ERN amplitude was associated with higher scores on a self-report measure of the broad externalizing construct that links these various indicators. In addition, the ERN was associated with a response-locked increase in anterior theta (4–7 Hz) oscillation; like the ERN, this theta response to errors was reduced among high-externalizing individuals. These findings suggest that neurobiologically based deficits in endogenous action monitoring may underlie generalized risk for an array of impulse-control problems

    Intravesical administration of combined hyaluronic acid (HA) and chondroitin sulfate (CS) for the treatment of female recurrent urinary tract infections: a European multicentre nested case-control study.

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    Published onlineJournal ArticleMulticenter StudyObservational StudyResearch Support, Non-U.S. Gov'tThis is the final version of the article. Available from BMJ Publishing Group via the DOI in this record.OBJECTIVES: To compare the clinical effectiveness of the intravesical administration of combined hyaluronic acid and chondroitin sulfate (HA+CS) versus current standard management in adult women with recurrent urinary tract infections (RUTIs). SETTING: A European Union-based multicentre, retrospective nested case-control study. PARTICIPANTS: 276 adult women treated for RUTIs starting from 2009 to 2013. INTERVENTIONS: Patients treated with either intravesical administration of HA+CS or standard of care (antimicrobial/immunoactive prophylaxis/probiotics/cranberry). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was occurrence of bacteriologically confirmed recurrence within 12 months. Secondary outcomes were time to recurrence, total number of recurrences, health-related quality of life and healthcare resource consumption. Crude and adjusted results for unbalanced characteristics are presented. RESULTS: 181 patients treated with HA+CS and 95 patients treated with standard of care from 7 centres were included. The crude and adjusted ORs (95% CI) for the primary end point were 0.77 (0.46 to 1.28) and 0.51 (0.27 to 0.96), respectively. However, no evidence of improvement in terms of total number of recurrences (incidence rate ratio (95% CI), 0.99 (0.69 to 1.43)) or time to first recurrence was seen (HR (95% CI), 0.99 (0.61 to 1.61)). The benefit of intravesical HA+CS therapy improves when the number of instillations is ≥ 5. CONCLUSIONS: Our results show that bladder instillations of combined HA+CS reduce the risk of bacteriologically confirmed recurrences compared with the current standard management of RUTIs. Total incidence rates and hazard rates were instead non-significantly different between the 2 groups after adjusting for unbalanced factors. In contrast to what happens with antibiotic prophylaxis, the effectiveness of the HA+CS reinstatement therapy improves over time. TRIAL REGISTRATION NUMBER: NCT02016118.This study was funded by an unrestricted grant from the TETI Association—study group for urogenital diseases. Members of the association were involved in the data collection and revised the manuscript

    Nano-mechanical properties of silver-welded YBCO bulks

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    The mechanical properties of melt-textured YBCO bulk boundaries are a topic of special interest especially in the manufacturing of superconductor devices for engineering applications. Instrumented indentation technique is a powerful tool widely employed to characterize the mechanical properties of small volumes. We presented results of the nanohardness (H) and Young’s modulus (E) across [001]-welds fabricated by silver welding. The residual imprints performed by a sharp tip indenter were observed by Field Emission Scanning Electron Microscope (FE-SEM) to investigate the different fracture mechanisms nucleated during the indentation process. Results show a decrease of the nanohardness across the grain boundary related to the appearance of a “welding path” free of Y-211 particles. The FE-SEM images show chipping and sink-in effects in that region. Remarkably, for zero-angle welds the mechanical properties are unaltered across the joint, thus probing the high quality of silver welds for large-scale applications.Peer ReviewedPostprint (published version

    Beating noise with abstention in state estimation

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    We address the problem of estimating pure qubit states with non-ideal (noisy) measurements in the multiple-copy scenario, where the data consists of a number N of identically prepared qubits. We show that the average fidelity of the estimates can increase significantly if the estimation protocol allows for inconclusive answers, or abstentions. We present the optimal such protocol and compute its fidelity for a given probability of abstention. The improvement over standard estimation, without abstention, can be viewed as an effective noise reduction. These and other results are exemplified for small values of N. For asymptotically large N, we derive analytical expressions of the fidelity and the probability of abstention, and show that for a fixed fidelity gain the latter decreases with N at an exponential rate given by a Kulback-Leibler (relative) entropy. As a byproduct, we obtain an asymptotic expression in terms of this very entropy of the probability that a system of N qubits, all prepared in the same state, has a given total angular momentum. We also discuss an extreme situation where noise increases with N and where estimation with abstention provides a most significant improvement as compared to the standard approach

    The effect of vibration therapy on neck myofascial trigger points: A randomized controlled pilot study

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    [EN] Background: The purpose of this study was to evaluate the effect of low-frequency self-administered vibration therapy into myofascial trigger points in the upper trapezius and levator scapulae on patients with chronic non-specific neck pain. Methods: Twenty-eight patients with chronic non-specific neck pain were randomly assigned into a vibration group, receiving 10 self-applied sessions of vibration therapy in the upper trapezius and levator scapulae trigger points; or a control group, receiving no intervention. Self-reported neck pain and disability (Neck Disability Index) and pressure pain threshold were assessed at baseline and after the first, fifth and 10th treatment sessions. Findings: Significant differences were found in the vibration group when compared to the control group after the treatment period: the vibration group reached lower Neck Disability Index scores (F = 4.74, P = .033, eta(2) = 0.07) and greater pressure pain threshold values (F = 7.56, P = .01, eta(2) = 0.10) than the control group. The vibration group reported a significant reduction in Neck Disability Index scores (chi(2) = 19,35, P = .00, Kendall's W = 0.28) and an increase in pressure pain threshold (chi(2) = 87,10, P = .00, Kendall's W = 0.73) between the assessment times over the course of the treatment. The mean increase in pressure pain threshold in the vibration group after the 10 sessions was 8.54 N/cm2, while the mean reduction in Neck Disability Index scores was 4.53 points. Interpretation: Vibration therapy may be an effective intervention for reducing self-reported neck pain and disability and pressure pain sensitivity in patients with chronic non-specific neck pain. This tool could be recommended for people with non-specific neck pain.Dueñas, L.; Zamora, T.; Lluch, E.; Artacho Ramírez, MÁ.; Mayoral, O.; Balasch Parisi, S.; Balasch-Bernat, M. (2020). The effect of vibration therapy on neck myofascial trigger points: A randomized controlled pilot study. Clinical Biomechanics. 78:1-9. https://doi.org/10.1016/j.clinbiomech.2020.1050711978Andrade Ortega, J. A., Delgado Martínez, A. D., & Ruiz, R. A. (2010). Validation of the Spanish Version of the Neck Disability Index. Spine, 35(4), E114-E118. doi:10.1097/brs.0b013e3181afea5dArmstrong, W. J., Grinnell, D. C., & Warren, G. S. (2010). The Acute Effect of Whole-Body Vibration on the Vertical Jump Height. Journal of Strength and Conditioning Research, 24(10), 2835-2839. doi:10.1519/jsc.0b013e3181e271ccBal, M. I., Sattoe, J. N. T., Roelofs, P. D. D. M., Bal, R., van Staa, A., & Miedema, H. S. (2016). Exploring effectiveness and effective components of self-management interventions for young people with chronic physical conditions: A systematic review. Patient Education and Counseling, 99(8), 1293-1309. doi:10.1016/j.pec.2016.02.012Bishop, M. D., Mintken, P., Bialosky, J. E., & Cleland, J. A. (2013). Patient Expectations of Benefit From Interventions for Neck Pain and Resulting Influence on Outcomes. Journal of Orthopaedic & Sports Physical Therapy, 43(7), 457-465. doi:10.2519/jospt.2013.4492Cagnie, B., Dewitte, V., Barbe, T., Timmermans, F., Delrue, N., & Meeus, M. (2013). Physiologic Effects of Dry Needling. Current Pain and Headache Reports, 17(8). doi:10.1007/s11916-013-0348-5Cagnie, B., Castelein, B., Pollie, F., Steelant, L., Verhoeyen, H., & Cools, A. (2015). Evidence for the Use of Ischemic Compression and Dry Needling in the Management of Trigger Points of the Upper Trapezius in Patients with Neck Pain. American Journal of Physical Medicine & Rehabilitation, 94(7), 573-583. doi:10.1097/phm.0000000000000266Celik, D., & Mutlu, E. K. (2013). Clinical Implication of Latent Myofascial Trigger Point. Current Pain and Headache Reports, 17(8). doi:10.1007/s11916-013-0353-8Chan, Y.-C., Wang, T.-J., Chang, C.-C., Chen, L.-C., Chu, H.-Y., Lin, S.-P., & Chang, S.-T. (2015). Short-term effects of self-massage combined with home exercise on pain, daily activity, and autonomic function in patients with myofascial pain dysfunction syndrome. Journal of Physical Therapy Science, 27(1), 217-221. doi:10.1589/jpts.27.217Chesterton, L. S., Barlas, P., Foster, N. E., Baxter, D. G., & Wright, C. C. (2003). Gender differences in pressure pain threshold in healthy humans. Pain, 101(3), 259-266. doi:10.1016/s0304-3959(02)00330-5Cummings, M., & Baldry, P. (2007). Regional myofascial pain: diagnosis and management. 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M., & Irnich, D. (2010). Discrepancy between prevalence and perceived effectiveness of treatment methods in myofascial pain syndrome: Results of a cross-sectional, nationwide survey. BMC Musculoskeletal Disorders, 11(1). doi:10.1186/1471-2474-11-32Franklin, N. C., Ali, M. M., Robinson, A. T., Norkeviciute, E., & Phillips, S. A. (2014). Massage Therapy Restores Peripheral Vascular Function After Exertion. Archives of Physical Medicine and Rehabilitation, 95(6), 1127-1134. doi:10.1016/j.apmr.2014.02.007Frey Law, L. A., Evans, S., Knudtson, J., Nus, S., Scholl, K., & Sluka, K. A. (2008). Massage Reduces Pain Perception and Hyperalgesia in Experimental Muscle Pain: A Randomized, Controlled Trial. The Journal of Pain, 9(8), 714-721. doi:10.1016/j.jpain.2008.03.009Gam, A. N., Warming, S., Larsen, L. H., Jensen, B., Høydalsmo, O., Allon, I., … Mathiesen, B. (1998). Treatment of myofascial trigger-points with ultrasound combined with massage and exercise – a randomised controlled trial. 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D., Coloma, P. S., Palma, F., Rey, A., & Falla, D. (2013). Effects of Deep Cervical Flexor Training on Pressure Pain Thresholds Over Myofascial Trigger Points in Patients With Chronic Neck Pain. Journal of Manipulative and Physiological Therapeutics, 36(9), 604-611. doi:10.1016/j.jmpt.2013.08.004Lobbezoo, F., Visscher, C. M., & Naeije, M. (2004). Impaired health status, sleep disorders, and pain in the craniomandibular and cervical spinal regions. European Journal of Pain, 8(1), 23-30. doi:10.1016/s1090-3801(03)00061-2Lu, X., Wang, Y., Lu, J., You, Y., Zhang, L., Zhu, D., & Yao, F. (2018). Does vibration benefit delayed-onset muscle soreness?: a meta-analysis and systematic review. Journal of International Medical Research, 47(1), 3-18. doi:10.1177/0300060518814999Lucas, K. R., Polus, B. I., & Rich, P. A. (2004). Latent myofascial trigger points: their effects on muscle activation and movement efficiency. 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    Diversity, competition, extinction: the ecophysics of language change

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    As early indicated by Charles Darwin, languages behave and change very much like living species. They display high diversity, differentiate in space and time, emerge and disappear. A large body of literature has explored the role of information exchanges and communicative constraints in groups of agents under selective scenarios. These models have been very helpful in providing a rationale on how complex forms of communication emerge under evolutionary pressures. However, other patterns of large-scale organization can be described using mathematical methods ignoring communicative traits. These approaches consider shorter time scales and have been developed by exploiting both theoretical ecology and statistical physics methods. The models are reviewed here and include extinction, invasion, origination, spatial organization, coexistence and diversity as key concepts and are very simple in their defining rules. Such simplicity is used in order to catch the most fundamental laws of organization and those universal ingredients responsible for qualitative traits. The similarities between observed and predicted patterns indicate that an ecological theory of language is emerging, supporting (on a quantitative basis) its ecological nature, although key differences are also present. Here we critically review some recent advances lying and outline their implications and limitations as well as open problems for future research.Comment: 17 Pages. A review on current models from statistical Physics and Theoretical Ecology applied to study language dynamic

    Nonlinear Jaynes-Cummings model of atom-field interaction

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    Interaction of a two-level atom with a single mode of electromagnetic field including Kerr nonlinearity for the field and intensity-dependent atom-field coupling is discussed. The Hamiltonian for the atom-field system is written in terms of the elements of a closed algebra, which has SU(1,1) and Heisenberg-Weyl algebras as limiting cases. Eigenstates and eigenvalues of the Hamiltonian are constructed. With the field being in a coherent state initially, the dynamical behaviour of atomic-inversion, field-statistics and uncertainties in the field quadratures are studied. The appearance of nonclassical features during the evolution of the field is shown. Further, we explore the overlap of initial and time-evolved field states.Comment: 14 pages, 6 figures is PS forma

    Forced expression of Lmx1b enhances differentiation of mouse ES cells into serotonergic neurons

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    The LIM homeodomain transcription factor Lmx1b is a key factor in the specification of the serotonergic neurotransmitter phenotype. Here, we explored the capacity of Lmx1b to direct differentiation of mouse embryonic stem (mES) cells into serotonergic neurons. mES cells stably expressing human Lmx1b were generated by lentiviral vector infection. Clones expressing Lmx1b at a low level showed increased neurogenesis and elevated production of neurons expressing serotonin, serotonin transporter, Tryptophan hydroxylase 2, and transcription factor Pet1, the landmarks of serotonergic differentiation. To explore the role of Lmx1b in the specification of the serotonin neurotransmission phenotype further, a conditional system making use of a floxed inducible vector targeted into the ROSA26 locus and a hormone-dependent Cre recombinase was engineered. This novel strategy was tested with the reporter gene encoding human placental alkaline phosphatase, and demonstrated its capacity to drive transgene expression in nestin+ neural progenitors and in Tuj1+ neurons. When it was applied to the inducible expression of human Lmx1b, it resulted in elevated expression of serotonergic markers. Treatment of neural precursors with the floor plate signal Sonic hedgehog further enhanced differentiation of Lmx1b-overexpressing neural progenitors into neurons expressing 5-HT, serotonin transporter, Tryptophan hydroxylase 2 and Pet1, when compared to Lmx1b-non expressing progenitors. Together, our results demonstrate the capacity of Lmx1b to specify a serotonin neurotransmitter phenotype when overexpressed in mESC-derived neural progenitors

    Topological reversibility and causality in feed-forward networks

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    Systems whose organization displays causal asymmetry constraints, from evolutionary trees to river basins or transport networks, can be often described in terms of directed paths (causal flows) on a discrete state space. Such a set of paths defines a feed-forward, acyclic network. A key problem associated with these systems involves characterizing their intrinsic degree of path reversibility: given an end node in the graph, what is the uncertainty of recovering the process backwards until the origin? Here we propose a novel concept, \textit{topological reversibility}, which rigorously weigths such uncertainty in path dependency quantified as the minimum amount of information required to successfully revert a causal path. Within the proposed framework we also analytically characterize limit cases for both topologically reversible and maximally entropic structures. The relevance of these measures within the context of evolutionary dynamics is highlighted.Comment: 9 pages, 3 figure

    Nanosecond spin lifetimes in single- and few-layer graphene-hBN heterostructures at room temperature

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    We present a new fabrication method of graphene spin-valve devices which yields enhanced spin and charge transport properties by improving both the electrode-to-graphene and graphene-to-substrate interface. First, we prepare Co/MgO spin injection electrodes onto Si++^{++}/SiO2_2. Thereafter, we mechanically transfer a graphene-hBN heterostructure onto the prepatterned electrodes. We show that room temperature spin transport in single-, bi- and trilayer graphene devices exhibit nanosecond spin lifetimes with spin diffusion lengths reaching 10μ\mum combined with carrier mobilities exceeding 20,000 cm2^2/Vs.Comment: 15 pages, 5 figure
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