500 research outputs found

    Pole analysis on the hadron spectroscopy of Λb→J/ΨpK−\Lambda_b\to J/\Psi p K^-

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    In this paper we study the J/ΨpJ/\Psi p spectroscopy in the process of Λb→J/ΨpK−\Lambda_b\to J/\Psi p K^-. The final state interactions of coupled channel J/ΨpJ/\Psi p ~-~ DˉΣc\bar{D} \Sigma_c~-~Dˉ∗Σc\bar{D}^{*} \Sigma_c are constructed based on K-matrix with the Chew-Mandelstam function. We build the Λb→J/ΨpK−\Lambda_b\to J/\Psi p K^- amplitude according to the Au-Morgan-Pennington method. The event shape is fitted and the decay width of Λb→J/ΨpK−\Lambda_b\to J/\Psi p K^- is used to constrain the parameters, too. With the amplitudes we extract out the poles and their residues. Our amplitude and pole analysis suggest that the Pc(4312)P_c(4312) should be DˉΣc\bar{D}\Sigma_c molecule, the Pc(4440)P_c(4440) could be an S-wave compact pentaquark state, and the structure around Pc(4457)P_c(4457) is caused by the cusp effect. The future experimental measurement of the decays of Λb→DˉΣcK−\Lambda_b\to \bar{D}\Sigma_c K^- and Λb→Dˉ∗ΣcK−\Lambda_b\to \bar{D}^*\Sigma_c K^- would further help to study the nature of these resonances.Comment: updated to the published versio

    Expanded CURB-65: A new score system predicts severity of community-acquired pneumonia with superior efficiency

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    Aim of this study was to develop a new simpler and more effective severity score for communityacquired pneumonia (CAP) patients. A total of 1640 consecutive hospitalized CAP patients in Second Affiliated Hospital of Zhejiang University were included. The effectiveness of different pneumonia severity scores to predict mortality was compared, and the performance of the new score was validated on an external cohort of 1164 patients with pneumonia admitted to a teaching hospital in Italy. Using age≥ 65 years, LDH>230u/L, albumin<3.5g/dL, platelet count<100×109/L, confusion, urea>7mmol/L, respiratory rate≥30/min, low blood pressure, we assembled a new severity score named as expanded-CURB-65. The 30-day mortality and length of stay were increased along with increased risk score. The AUCs in the prediction of 30-day mortality in the main cohort were 0.826 (95%CI, 0.807–0.844), 0.801 (95%CI, 0.781–0.820), 0.756 (95%CI, 0.735–0.777), 0.793 (95%CI, 0.773–0.813) and 0.759 (95%CI, 0.737–0.779) for the expanded-CURB-65, PSI, CURB-65, SMART-COP and A-DROP, respectively. The performance of this bedside score was confirmed in CAP patients of the validation cohort although calibration was not successful in patients with health care-associated pneumonia (HCAP). The expanded CURB-65 is objective, simpler and more accurate scoring system for evaluation of CAP severity, and the predictive efficiency was better than other score systems

    Reinstatement of the corticioid genus Leifia (Hymenochaetales, Basidiomycota) with a new species L. brevispora from Hubei, Central China

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    The monotypic genus Leifia was previously considered to be a later synonym of Odonticium. With the morphological and phylogenetic evidence provided by an additional four East Asian specimens, we propose to reinstate Leifia as an independent genus in Hymenochaetales. Leifia morphologically differs from Odonticium by its grandinioid hymenophore with hyphal strands, numerous thick-walled cystidia with an invaginated apical end and narrowly and thick-walled basidia. The phylogeny generated from the current data set of ITS and 28S regions indicates that Leifia forms a sister clade to Odonticium. Besides the generic type Leifia flabelliradiata in the Leifia clade, two specimens, collected from Hubei, Central China, are newly introduced as Leifia brevispora. This new species is the second species of Leifia and differs from the generic type by its shorter basidiospores and distribution in warm-temperate to subtropical areas in East Asia. The additional two specimens, collected from Da Lat, Viet Nam, differ morphologically, both from each other and from known species of Leifia, but more samples need to be examined before further taxonomic decisions can be made

    A 1-hydroxy-2,4-diformylnaphthalene-based fluorescent probe and its detection of sulfites/bisulfite

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    A novel 1-hydroxy-2,4-diformylnaphthalene-based fluorescent probe L was synthesized by a Knoevenagel reaction and exhibited excellent sensitivity and selectivity towards sulfite ions (SO32−) and bisulfite ions (HSO3−). The detection limits of the probe L were 0.24 μM using UV-Vis spectroscopy and 9.93 nM using fluorescence spectroscopy, respectively. Furthermore, the fluorescent probe L could be utilized for detection in real water samples with satisfactory recoveries in the range 99.20%~104.30% in lake water and 100.00%~104.80% in tap water by UV-Vis absorption spectrometry, and in the range 100.50%~108.60% in lake water and 102.70%~103.80% in tap water by fluorescence spectrophotometry

    Experimental test of high-dimensional quantum contextuality based on contextuality concentration

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    Contextuality is a distinctive feature of quantum theory and a fundamental resource for quantum computation. However, existing examples of contextuality in high-dimensional systems lack the necessary robustness required in experiments. Here we address this problem by identifying a family of noncontextuality inequalities whose maximum quantum violation grows with the dimension of the system. At first glance, this contextuality is the single-system version of an extreme form of multipartite Bell nonlocality. What is interesting is that the single-system version achieves the same degree of contextuality but using a Hilbert space of {\em lower} dimension. That is, contextualize "concentrates" as the degree of contextuality per dimension increases. We demonstrate the usefulness of this result by showing the experimental observation of contextuality in a single system of dimension seven. By simulating sequences of quantum ideal measurements in an all-optical setup using projective measurements on structured light, we report a violation of 68.7 standard deviations of the simplest of the noncontextuality inequalities identified. Our results advance the investigation of high-dimensional contextuality, its connection to the Clifford algebra, and its role in quantum computation.Comment: 7+5 pages, 4+2 figures. Comments are welcom
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