342 research outputs found

    Feasibility of extracting a Σ\Sigma^- admixture probability in the neutron-rich Λ10^{10}_{\Lambda}Li hypernucleus

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    We examine theoretically production of the neutron-rich Λ10^{10}_{\Lambda}Li hypernucleus by a double-charge exchange (π\pi^-, K+K^+) reaction on a 10^{10}B target with distorted-wave impulse approximation calculations. The result shows that the magnitude and shape of the calculated spectrum at 1.20 GeV/c by a one-step mechanism πpK+Σ\pi^-p \to K^+ \Sigma^- via Σ\Sigma^- doorways caused by a ΣpΛn\Sigma^-p \leftrightarrow \Lambda n coupling can explain the recent experimental data, and the Σ\Sigma^- admixture probability in Λ10^{10}_{\Lambda}Li is found to be the order of 101^{-1} %. The (π\pi^-, K+K^+) reaction provides a capability of extracting properties of wave functions with Λ\Lambda-Σ\Sigma coupling effects in neutron-rich nuclei, together with the reaction mechanism.Comment: 13 pages, 3 figure

    Adopting Virtual Role Play in Family Medicine Training During COVID-19 Pandemic

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    Stochastic Variational Search for ΛΛ4^{4}_{\Lambda\Lambda}H

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    A four-body calculation of the pnΛΛpn\Lambda\Lambda bound state, $^{\ 4}_{\Lambda\Lambda}H,isperformedusingthestochasticvariationalmethodandphenomenologicalpotentials.TheH, is performed using the stochastic variational method and phenomenological potentials. The NN,, \Lambda N,and, and \Lambda\LambdapotentialsaretakenfromarecentLetterbyFilikhinandGal,PRL89,172502(2002).AlthoughtheirFaddeevYakubovskycalculationfoundnoboundstatesolutionoverawiderangeof potentials are taken from a recent Letter by Filikhin and Gal, PRL{\bf 89}, 172502 (2002). Although their Faddeev-Yakubovsky calculation found no bound-state solution over a wide range of \Lambda\Lambdainteractionstrengths,thepresentvariationalcalculationgivesaboundstateenergy,whichisclearlylowerthanthe interaction strengths, the present variational calculation gives a bound-state energy, which is clearly lower than the _\Lambda^3{H}+\Lambdathreshold,evenforaweak threshold, even for a weak \Lambda\Lambdainteractionstrengthdeducedfromarecentexperimental interaction strength deduced from a recent experimental B_{\Lambda\Lambda}(^{6}_{\Lambda\Lambda}{He})value.Thebindingenergiesobtainedarecloseto,andslightlylargerthan,thevaluesobtainedfromthethreebody value. The binding energies obtained are close to, and slightly larger than, the values obtained from the three-body d\Lambda\Lambda$ model in the Letter.Comment: Corrected typos, added addtional calculations regarding a truncated to l=0 interaction model, 4 pages, 3 figure

    Hyperonic mixing in five-baryon double-strangeness hypernuclei in a two-channel treatment

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    Properties of hypernuclei ΛΛ5_{\Lambda \Lambda}^5H and ΛΛ5_{\Lambda \Lambda }^5He are studied in a two-channel approach with explicit treatment of coupling of channels ^3\text{Z}+\Lambda+\Lambda and \alpha+\Xi. Diagonal \Lambda\Lambda and coupling \Lambda\Lambda-\Xi N interactions are derived within G-matrix procedure from Nijmegen meson-exchange models. Bond energy \Delta B_{\Lambda\Lambda} in ΛΛ5_{\Lambda \Lambda}^5He exceeds significantly that in ΛΛ5_{\Lambda \Lambda}^5H due to the channel coupling. Diagonal \Xi\alpha attraction amplifies the effect, which is sensitive also to \Lambda-core interaction. The difference of the \Delta B_{\Lambda\Lambda} values can be an unambiguous signature of the \Lambda\Lambda-\Xi N coupling in \Lambda\Lambda hypernuclei. However, improved knowledge of the hyperon-nucleus potentials is needed for quantitative extraction of the coupling strength from future data on the \Lambda\Lambda hypernuclear binding energies.Comment: 11 pages with 3 figures; Phys. Rev. C, accepte

    The Λ\Lambda-Σ\Sigma coupling effect in the neutron-rich Λ\Lambda-hypernucleus Λ10_{\Lambda}^{10}Li by microscopic shell model

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    We investigate the structure of the neutron-rich Λ\Lambda-hypernucleus Λ10_{\Lambda}^{10}Li by using microscopic shell-model calculations considering a Λ\Lambda-Σ\Sigma coupling effect. The calculated Σ\Sigma-mixing probability in the Λ10_{\Lambda}^{10}Li ground state is found to be about 0.34 % which is coherently enhanced by the Λ\Lambda-Σ\Sigma coupling configurations, leading to the energy shift 0.28 MeV which is about 3 times larger than that in Λ7_{\Lambda}^{7}Li. The importance of the Σ\Sigma configuration obtained by the ΣN\Sigma N interaction and the potentiality of the neutron-rich environment are discussed.Comment: 6 figure

    Determination of iodine value of palm oil based on triglyceride composition

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    The triglyceride (TG) composition of palm oil is normally determined by high-performance liquid chromatography (HPLC). The HPLC chromatograms indicated a good separation of most of the TG components in the oil. The TG can be classified based on either the TG groups, i.e., triunsaturated, monosaturated, disaturated, or trisaturated, or the number of double bonds, i.e., zero, one, two, three, or four double bonds. The more unsaturated the fatty acid, the greater the iodine value (IV). Therefore, it is hypothesized that the IV of an oil can be determined based upon the TG composition of the oil. Based on the TG groups, stepwise regression analysis showed that the areas of the disaturated, trisaturated, and triunsaturated TG peaks could predict the IV with a coefficient of determination (R2) of 0.990. The regression based on the number of double bonds yielded a good regression equation with R2=0.992. The important variables were the peak area of the fatty acids that contained zero, one, two, and three double bonds. This study concludes that the TG composition can be used to predict the IV of palm oil. The best prediction model is obtained by using the number of double bonds in the TG as the independent variable

    Inter-prescriber variability in the decision to prescribe antibiotics to febrile patients attending primary care in Myanmar

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    Background: Most antibiotic prescribing occurs in primary care. Even within the same health facility, there may be differences between prescribers in their tendency to prescribe antibiotics, which may be masked by summary data. We aimed to quantify prescriber variability in antibiotic prescription to patients with acute fever in primary care clinics in Myanmar. Methods: We conducted a secondary analysis of prescribing data from 1090 patient consultations with 40 prescribing doctors from a trial investigating the effect of point-of-care C-reactive protein (CRP) tests on antibiotic prescription for acute fever. We used multilevel logistic regression models to assess inter-prescriber variability in the decision to prescribe antibiotics. Results: The median odds ratio (MOR) in the unadjusted model was 1.82 (95% CI: 1.47–2.56) indicating that when two prescribers from this population are randomly selected then in half of these pairs the odds of prescription will be greater than 1.82-fold higher in one prescriber than the other. The estimated variability from this sample of prescribers corresponds to a population of prescribers where the top 25% of prescribers will prescribe antibiotics to over 41% of patients while the bottom 25% will prescribe antibiotics to less than 23% of patients. Inter-prescriber variation in antibiotic prescribing remained after adjustment for patient characteristics and CRP information (P < 0.001). Conclusions: Despite sharing the same management guidelines, there was substantial inter-prescriber variation in antibiotic prescription to patients with acute fever. This variation should be considered when designing trials and stewardship programmes aiming to reduce inappropriate antibiotic prescribing
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