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Objective This study aimed to investigate the epidemiology and changes in antibacterial susceptibility of children in Shenmu City, northern Shaanxi, and provide a basis for rational drug use.Methods The distribution and drug resistance pattern of pathogenic bacteria isolated from children were retrospectively analysed.Results A total of 573 strains of pathogens were cultivated. A total of 201 (35.07%) strains of Gram-positive cocci and 183 (31.93%) strains of Gram-negative cocci were detected. A total of 189 (32.98%) strains of fungi were detected. The resistance rate of Staphylococcus to penicillin was 100% and that to erythromycin was 90.69%. There were varying degrees of resistance to other drugs, but no single strain had vancomycin resistance. Gram-negative bacilli were generally resistant to ampicillin, but had low resistance to the combined preparation of enzyme inhibitors, quinolones, and aminoglycosides, and were highly sensitive to imipenem and meropenem.Conclusion Gram-negative bacilli are the main pathogens of bacterial infection in the paediatric ward. Strengthening clinical monitoring of bacterial distribution in paediatric clinical isolates and understanding changes in drug resistance are important for guiding the rational use of antibiotics. These measures could also prevent emergence and spreading of resistant strains.

We use QCD sum rules to study the mass spectra of P-wave charmed baryons of the SU(3) flavor 6F. We also use light cone sum rules to study their S- and D-wave decays into ground-state charmed baryons together with light pseudoscalar and vector mesons. We work within the framework of heavy quark effective theory, and we also consider the mixing effect. Our results can explain many excited charmed baryons as a whole, including the Σc(2800)0, Ξc(2923)0, Ξc(2939)0, Ξc(2965)0, Ωc(3000)0, Ωc(3050)0, Ωc(3066)0, Ωc(3090)0, and Ωc(3119)0. Their masses, mass splittings within the same multiplets, and decay properties are extracted for future experimental searches. [ABSTRACT FROM AUTHOR]

We systematically study mass spectra and decay properties of P-wave Ξ′c baryons of the SU(3) flavor 6F, using the methods of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. Our results suggest that the three excited Ξ0c baryons recently observed by LHCb can be well explained as P-wave Ξ′c baryons: the Ξc(2923)0 and Ξc(2939)0 are partner states of JP=1/2- and 3/2-, respectively, both of which contain one λ-mode orbital excitation; the Ξc(2965)0 has JP=3/2- and also contains one λ-mode orbital excitation. We propose to search for another P-wave Ξ′c state of JP=5/2- in the ΛcK/Ξcπ mass spectral in future experiments. Its mass is about 56+30-35  MeV larger than the Ξc(2965)0, and its width is about 18.1+19.7-8.3  MeV. [ABSTRACT FROM AUTHOR]

We investigate P-wave bottom baryons of the SU(3) flavor 6F, and systematically study their D-wave decays into ground-state bottom baryons and pseudoscalar mesons. Together with [H. X. Chen et al., Phys. Rev. D 91, 054034 (2015); Q. Mao et al., Phys. Rev. D 92, 114007 (2015); H. X. Chen et al., Phys. Rev. D 95, 094008 (2017); H. M. Yang et al.,Eur. Phys. J. C 80, 80 (2020)], a rather complete study is performed on both mass spectra and decay properties of P-wave bottom baryons, using the method of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. Among all the possibilities, we find four Σb, four Ξ′b, and six Ωb baryons, with limited widths and so capable of being observed. Their masses, mass splittings within the same multiplets, and decay properties are extracted (summarized in Table VI) for future experimental searches. [ABSTRACT FROM AUTHOR]

We use the method of QCD sum rules within the framework of heavy quark effective theory to study the mass spectrum of the Σb(6097)± and Ξb(6227)-, and use the method of light cone sum rules still within the heavy quark effective theory to study their decay properties. Our results suggest that they can be well interpreted as P-wave bottom baryons with the spin-parity JP=3/2-. They belong to the baryon doublet [6F,2,1,λ], where the total and spin angular momenta of the light degree of freedom are jl=2 and sl=1, and the orbital angular momentum is between the bottom quark and the two-light-quark system (λ-type). This doublet contains six bottom baryons, and we predict masses (mass differences) and decay widths of the other four states to be MΩb(3/2-)=6.46±0.12  GeV, ΓΩb(3/2-)=58+65-33  MeV, MΣb(5/2-)-MΣb(3/2-)=13±5  MeV, MΞ′b(5/2-)-MΞ′b(3/2-)=12±5  MeV, and MΩb(5/2-)-MΩb(3/2-)=11±5  MeV. We propose to search for them in further LHCb experiments. [ABSTRACT FROM AUTHOR]