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In recent years, hypervirulent Klebsiella pneumoniae (hvKp) has received greater attention. It mainly infects diabetic patients and typically causes a hepatic abscess. Here, we report a case of hvKp that caused forearm muscle and soft tissue infection in addition to bacteremia, hepatic and pulmonary abscess, and hyperglycemia. The patient’s condition stabilized after comprehensive treatment. She eventually recovered and was discharged after several debridement and flap operations. At 9 months of follow-up, no signs of infectious recurrence were noted, and the hyperglycemia resolved. Here, we detail important clinical features of a severe hvKp case diagnosed in an otherwise healthy individual. This report underscores the potential of hvKp to cause deep tissue infection and present with clinical symptoms similar to gas gangrene. Symptom onset in the setting of hvKp infection is usually gradual and misdiagnosis is common. The diagnosis of hvKp should be routinely considered in the clinical setting, and be strongly suspected when presenting with characteristic epidemiological, clinical and laboratory features. Although diabetes is a predisposing factor to hvKp infection, hyperglycemia appeared to manifest as a consequence of hvKp infection in this patient.

Poly(propylene carbonate) (PPC) has aroused extensive attention in the biomaterial field because of its excellent biocompatibility and appropriate degradability, but surface hydrophobicity and bioinertness limit its applications for bone repair and tissue engineering. In this study, a bioactive PPC/laponite (LAP) nanocomposite (PL) was prepared by a melt-blending method, and a microporous surface on PPC and PL (PT and PLT) was created by sodium hydroxide (NaOH) treatment. The results demonstrated that the surface roughness, hydrophilicity, surface energy, and degradability as well as protein adsorption of PLT were obviously improved compared with PPC. Moreover, the degradability of PLT was remarkably enhanced with a slight increase of pH values in Tris-HCl solution. Furthermore, adhesion and proliferation as well as osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) to PLT were significantly promoted compared with PPC. The results suggested that incorporating LAP into PPC obviously improved the surface performance of PL (with nanotopography), and surface treatment with NaOH further enhanced surface properties of PLT (with micronanotopography and hydrophilic groups), which significantly promoted responses of rBMSCs. In short, PLT displayed excellent cytocompatibility, which would have great potential for bone regeneration.

We propose a new method to estimate the directions-of-arrival (DOA) of target for passive bistatic radar (PBR) system in coherent environment. Since the illuminators of PBR is non-cooperative, the performance of the DOA estimation suffers from limited snapshots and low signal-to-noise ratio (SNR) In addition, the interferences of strong direct wave and multipath signals are also intractable to deal with. In this method a sparse representation of the signals is firstly established, and the iterative adaptive approach (IAA) is applied to spatial spectrum estimation. Then we can eliminate the direct wave in the airspace and obtain the DOA estimation of the scattered signal of target by searching for peaks. Compared with the previous works, the proposed method achieves improved DOA estimation accuracy. Simulation results validate the better performance of the proposed method.

The epidermis and dermis of human skin have randomly distributed microstructures, so we can sense external stimuli with high sensitivity and a low detection limit. Herein, a biomimetic microstructure sensor was fabricated using sandpaper as a template. The finite element simulation results show that the strain sensing property of the sensor can be improved by introducing a biomimetic microstructure, which is consistent with the experimental results. The gauge factor of the microstructure sensor (20.64) is 4.81 times that of the planar structure sensor (4.29) in the linear strain range from 0.1% to 1.0%. The microstructure sensor has a very low detection limit (0.1% strain), fast response (53.6 ms), and good cycling durability (3000 cycles). In addition, the microstructure sensor can achieve real-time monitoring of human motion and physiological signals, such as finger bending, knee bending, and breathing frequency. The proposed microstructure sensor is expected to have broad application prospects in motion monitoring and health-care fields.