254 research outputs found

    Структура и свойства керамических композитов, модифицированных углеродными нанотрубками и нановолокнами Al2O3

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    Работа направлена на установление закономерности влияния вводимых добавок одностенных/многостенных УНТ и нановолокон Al2O3 на структуру, фазовый состав и физико-механические свойства композитов на основе оксидов алюминия и циркония. Показано, что использование УНТ и нановолокон Al2O3 при изготовлении композитов, может приводить к существенному повышению трещиностойкость керамических материалов. Кроме того, варьируя концентрацию вводимых добавок, можно получать оптимальные свойства керамических композитов для конкретных применений.The work is aimed at establishing the regularity of the influence of the introduced additives of single-wall/multi-walled CNTs and Al2O3 nanofibers on the structure, phase composition, and mechanical properties of composites based on alumina and zirconia. It is shown that the use of CNTs and Al2O3 nanofibers in the manufacture of composites can lead to a significant increase in the fracture toughness of ceramic materials. In addition, by varying the concentration of the added additives, it is possible to obtain the optimal properties of ceramic composites for specific applications

    Using SDRT to analyze pathological conversations. Logicality, rationality and pragmatic deviances

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    International audienceSchizophrenia is well-known among mental illnesses for the severity of the thought dis- orders it involves, and for their widespread and spectacular manifestations ranging from deviant social behavior to delusion, not to mention affective and sensory distortions. Confronted with such a pathological con- versation, any "ordinary" speaker intuitively feels that there are some incoherencies or discontinuities. The aim of this research is to account for these using both pragmatics and formal semantics. Linguistics, especially semantics and pragmatics, is thus central to this work

    How to improve prescription of inhaled salbutamol by providing standardised feedback on administration: a controlled intervention pilot study with follow-up

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    Background: The effectiveness of inhaled salbutamol in routine care depends particularly on prescribed dosage and applied inhalation technique. To achieve maximum effectiveness and to prevent drug-related problems, prescription and administration need to work in concert. Methods: We performed a controlled intervention pilot study with 4 consecutive groups in a general paediatric unit and assessed problems in salbutamol prescribing and administration. Control group [i]: Routine care without additional support. First intervention group [ii]: We carried out a teaching session for nurses aimed at preventing problems in inhalation technique. Independently from this, a pharmacist counselled physicians on problems in salbutamol prescribing. Second intervention group [iii]: Additionally to the first intervention, physicians received standardised feedback on the inhalation technique. Follow-up group [iv]: Subsequently, without any delay after the second intervention group had been completed, sustainability of the measures was assessed. We performed the chi-square test to calculate the level of significance with p ≤ 0.05 to indicate a statistically significant difference for the primary outcome. As we performed multiple testing, an adjusted p ≤ 0.01 according to Bonferroni correction was considered as significant. Results: We included a total of 225 patients. By counselling the physicians, we reduced the number of patients with problems from 55% to 43% (control [i] vs. first intervention [ii], n.s.). With additional feedback to physicians, this number was further reduced to 25% ([i] vs. [iii], p < 0.001). In the follow-up [iv], the number rose again to 48% (p < 0.01 compared to feedback group). Conclusions: Teaching nurses, counselling physicians, and providing feedback on the quality of inhalation technique effectively reduced problems in salbutamol treatment. However, for success to be sustained, continuous support needs to be provided. Trial registration: German Clinical Trials register: DRKS00006792

    Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR

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    The possibility of measuring the proton electromagnetic form factors in the time-like region at FAIR with the \PANDA detector is discussed. Detailed simulations on signal efficiency for the annihilation of pˉ+p\bar p +p into a lepton pair as well as for the most important background channels have been performed. It is shown that precision measurements of the differential cross section of the reaction pˉ+pe++e\bar p +p \to e^++ e^- can be obtained in a wide angular and kinematical range. The individual determination of the moduli of the electric and magnetic proton form factors will be possible up to a value of momentum transfer squared of q214q^2\simeq 14 (GeV/c)2^2. The total pˉ+pe++e\bar p +p\to e^++e^- cross section will be measured up to q228q^2\simeq 28 (GeV/c)2^2. The results obtained from simulated events are compared to the existing data. Sensitivity to the two photons exchange mechanism is also investigated.Comment: 12 pages, 4 tables, 8 figures Revised, added details on simulations, 4 tables, 9 figure

    Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR

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    Simulation results for future measurements of electromagnetic proton form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel pˉpe+e\bar p p \to e^+ e^- is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e.\textit{i.e.} pˉpπ+π\bar p p \to \pi^+ \pi^-, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance

    Study of J/ψJ/\psi and ψ(3686)Σ(1385)0Σˉ(1385)0\psi(3686)\rightarrow\Sigma(1385)^{0}\bar\Sigma(1385)^{0} and Ξ0Ξˉ0\Xi^0\bar\Xi^{0}

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    We study the decays of J/ψJ/\psi and ψ(3686)\psi(3686) to the final states Σ(1385)0Σˉ(1385)0\Sigma(1385)^{0}\bar\Sigma(1385)^{0} and Ξ0Ξˉ0\Xi^0\bar\Xi^{0} based on a single baryon tag method using data samples of (1310.6±7.0)×106(1310.6 \pm 7.0) \times 10^{6} J/ψJ/\psi and (447.9±2.9)×106(447.9 \pm 2.9) \times 10^{6} ψ(3686)\psi(3686) events collected with the BESIII detector at the BEPCII collider. The decays to Σ(1385)0Σˉ(1385)0\Sigma(1385)^{0}\bar\Sigma(1385)^{0} are observed for the first time. The measured branching fractions of J/ψJ/\psi and ψ(3686)Ξ0Ξˉ0\psi(3686)\rightarrow\Xi^0\bar\Xi^{0} are in good agreement with, and much more precise, than the previously published results. The angular parameters for these decays are also measured for the first time. The measured angular decay parameter for J/ψΣ(1385)0Σˉ(1385)0J/\psi\rightarrow\Sigma(1385)^{0}\bar\Sigma(1385)^{0}, α=0.64±0.03±0.10\alpha =-0.64 \pm 0.03 \pm 0.10, is found to be negative, different to the other decay processes in this measurement. In addition, the "12\% rule" and isospin symmetry in the J/ψJ/\psi and ψ(3686)ΞΞˉ\psi(3686)\rightarrow\Xi\bar\Xi and Σ(1385)Σˉ(1385)\Sigma(1385)\bar{\Sigma}(1385) systems are tested.Comment: 11 pages, 7 figures. This version is consistent with paper published in Phys.Lett. B770 (2017) 217-22

    Observation of an anomalous line shape of the ηπ+π\eta^{\prime}\pi^{+}\pi^{-} mass spectrum near the ppˉp\bar{p} mass threshold in J/ψγηπ+πJ/\psi\rightarrow\gamma\eta^{\prime}\pi^{+}\pi^{-}

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    Using 1.09×1091.09\times10^{9} J/ψJ/\psi events collected by the BESIII experiment in 2012, we study the J/ψγηπ+πJ/\psi\rightarrow\gamma\eta^{\prime}\pi^{+}\pi^{-} process and observe a significant abrupt change in the slope of the ηπ+π\eta^{\prime}\pi^{+}\pi^{-} invariant mass distribution at the proton-antiproton (ppˉp\bar{p}) mass threshold. We use two models to characterize the ηπ+π\eta^{\prime}\pi^{+}\pi^{-} line shape around 1.85 GeV/c21.85~\text{GeV}/c^{2}: one which explicitly incorporates the opening of a decay threshold in the mass spectrum (Flatt\'{e} formula), and another which is the coherent sum of two resonant amplitudes. Both fits show almost equally good agreement with data, and suggest the existence of either a broad state around 1.85 GeV/c21.85~\text{GeV}/c^{2} with strong couplings to ppˉp\bar{p} final states or a narrow state just below the ppˉp\bar{p} mass threshold. Although we cannot distinguish between the fits, either one supports the existence of a ppˉp\bar{p} molecule-like state or bound state with greater than 7σ7\sigma significance
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