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Background and Objective. Haemophilus influenzae (HI) is a common cause of community-acquired pneumonia in children. In many countries, HI strains are increasingly resistant to ampicillin and other commonly prescribed antibiotics, posing a challenge for effective clinical treatment. This study was undertaken to determine the antibiotic resistance profiles of HI isolates from Chinese children and to provide guidelines for clinical treatment. Methods. Our Infectious Disease Surveillance of Pediatrics (ISPED) collaboration group includes six children’s hospitals in different regions of China. The same protocols and guidelines were used by all collaborators for the culture and identification of HI. The Kirby–Bauer method was used to test antibiotic susceptibility, and a cefinase disc was used to detect β-lactamase activity. Results. We isolated 2073 HI strains in 2016: 83.9% from the respiratory tract, 11.1% from vaginal secretions, and 0.5% from blood. Patients with respiratory isolates were significantly younger than nonrespiratory patients (P<0.001). Of all 2073 strains, 50.3% were positive for β-lactamase and 58.1% were resistant to ampicillin; 9.3% were β-lactamase-negative and ampicillin-resistant. The resistance rates of the HI isolates to trimethoprim-sulfamethoxazole, azithromycin, cefuroxime, ampicillin-sulbactam, cefotaxime, and meropenem were 71.1%, 32.0%, 31.2%, 17.6%, 5.9%, and 0.2%, respectively. Conclusions. More than half of the HI strains isolated from Chinese children were resistant to ampicillin, primarily due to the production of β-lactamase. Cefotaxime and other third-generation cephalosporins could be the first choice for the treatment of ampicillin-resistant HI infections.

Lithium–oxygen (Li–O2) batteries have been widely recognized as appealing power systems for their extremely high energy density versus common Li-ion batteries. However, there are still lots of issues that need to be addressed toward the practical application. Here, free-standing Co-doped NiO three-dimensional nanosheets were prepared by a hydrothermal synthesis method and directly employed as the air-breathing cathode of the Li–O2 battery. The morphological phenomenon and electrochemical performance of the as-prepared cathode material were characterized by high-resolution scanning electron microscopy, X-ray diffraction, cyclic voltammetry, galvanostatic charge–discharge tests, and electrochemical impedance spectroscopy measurements. The Co-doped NiO electrode delivered a maximum discharge capacity of around 12 857 mA h g–1 with a low overpotential (0.82 V) at 200 mA g–1. Under upper-limit specific capacities of 500 mA h g–1 at 400 mA g–1, the Li–O2 batteries exhibited a long cycle life of 165 cycles. Compared with the undoped NiO electrode, the Li–O2 battery based on the Co-doped NiO cathode showed significantly higher oxygen reduction reaction and oxygen evolution reaction activities. This superior electrochemical performance is because of the partial substitution of Ni2+ in the NiO matrix by Co2+ to improve the p-type electronic conductivity of NiO. In addition, the morphology and specific surface area of NiO are affected by Co doping, which can expand the electrode–electrolyte contact area and lead to sufficient space for Li2O2 deposition. This approach harnesses the great potential of Co-doped NiO nanosheets for practical applications as advanced electrodes for rechargeable Li–O2 batteries.

Article impact statementConcurrent effects of different types of human disturbance on wildlife communities need to be considered in conservation planning.