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With the explosive growth of distributed renewable energy connected to the power system, the application of AC–DC hybrid distribution network with power electronic transformer (PET) becomes more and more extensive. An equivalent loss model is formulated from the perspective of the internal topology of PET. Then, a novel PET power flow model is established to obtain the relationship between the three ports. On this basis, reactive power of PV nodes connecting PET and distributed renewable generation is modified by establishing an equivalent impedance matrix, thus the forward–backward sweep load flow calculation method is improved for power flow calculation and volt/var control of distribution network. Different from traditional reactive optimization methods, a multi-objective reactive power optimization model considering the PET and two types of photovoltaic converters is established in this paper, with the targets of minimizing voltage deviation and power loss simultaneously. Finally, the numerical simulation shows the accuracy, rationality, and feasibility of the proposed method.

Soft tissue defects in the weight-bearing heel represent a reconstructive challenge because of tissue complexity and lack of local/regional coverage. This study presents our reconstruction outcomes of different defect aetiologies, reconstruction timing, and flap selection.Patients with weight-bearing heel defects who underwent free tissue transfer from 2003 to 2014 and with at least 6 months of follow-up were retrospectively reviewed. Flap types (fasciocutaneous vs muscle/musculocutaneous), timing of reconstruction (early vs subacute vs delayed), and defect aetiology were compared in terms of flap failure, vascular complications, and ulceration.Seventy-four flaps were used to reconstruct weight-bearing heel defects in 70 patients. Defect aetiology included trauma in 53 patients (75%), chronic wound in 12 patients (17%), and tumour resection in 6 patients (8%). Flap survival was 97% (72/74). There was no significant difference in flap failures between muscle and fasciocutaneous flaps. The timing of reconstruction showed no difference in flap survival. There was a significant difference in ulceration rate between the trauma and non-trauma groups (p = 0.001). Twenty-eight ulcers (39%) developed, 12 (43%) of which presented 3 years postoperatively, while only 6 cases (21%) presented within one year postoperatively.Our experience represents one of the highest survival rates reported regarding free flap weight-bearing heel reconstruction. The anterolateral thigh flap was our first choice for extensive heel defects. Ulceration incidence was directly related to trauma and tends to develop 3 years after reconstruction. Delayed reconstruction was at least as safe as early or subacute reconstruction though with less need for debulking.

Magnesium (Mg) and some of its alloys are considered promising biodegradable metallic biomaterials for bone implant applications. The osteogenesis effect of Mg alloys is widely reported; however, the underlying mechanisms are still not clear. In this study, pure Mg, Mg-3Zn, and Mg-2Zn-1Mn were prepared, and their degradation behavior, biocompatibility, and osteogenesis effect were systematically assessed both in vitro and in vivo. Primary rat bone marrow-derived mesenchymal stem cells (BMSCs) were used to evaluate the biocompatibility of the prepared Mg alloys, and a rat femur fracture model was used to assess the stimulating effect of these alloys on bone-tissue formation. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. Extracts of the three materials showed significant stimulating effects on osteogenic differentiation of BMSCs along with non-cytotoxicity. Implantation of Mg-2Zn-1Mn wires into the femur of rats demonstrated superior histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. Moreover, the results of both in vitro and in vivo assessments demonstrated that bone morphogenetic proteins and fibroblast growth factor receptors are involved in the stimulating effect of Mg alloys. STATEMENT OF SIGNIFICANCE: This work reports the degradation behavior, biocompatibility, and osteogenic effect of pure Mg and Mg-3Zn and Mg-2Zn-1Mn alloys in both in vitro and in vivo conditions. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. The extracts of the three materials showed a significant stimulating effect on osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs) along with non-cytotoxicity. Mg-2Zn-1Mn wires implanted into the femur of rats showed good histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. The results of the present study suggest that bone morphogenetic proteins (BMPs) and fibroblast growth factor receptors (FGFRs) are involved in the stimulating effect of Mg alloys on osteogenesis.

The sedimentary basin is a basic geological unit in the Earth system: its formation and evolution are controlled mainly by plate tectonics and geodynamics, which have produced a variety of basin types. The development and evolution of various basins depend not only on the tectonic effect of lithospheric plate but also on sublithospheric, and Earth surface actions. Basin classification schemes based on the theories of platform–geosyncline or plate tectonics could neither include all basin types nor reflect the complex processes of basin formation and evolution. From the viewpoint of Earth system, we proposed a new basin classification scheme based on geodynamic mechanism—that is, lithospheric plate, sublithospheric, and Earth surface actions. In our geodynamic classification, we employed a series of geodynamic settings of basin formation and evolution, including the lithospheric plate, sublithospheric, and Earth surface environments, the dynamic regimes of basin formation and evolution, such as tectonic setting (extension, compression and shearing), the thermal processes and gravity effects, the various natures of basin basement and crustal types (continental, oceanic, or transitional crust), and the history of basin sedimentary filling and tectonic paleogeography successively, as the controlling factors for basin classification. This new geodynamic classification scheme highlights both the role of the lithosphere and the effects of the sublithospheric and the Earth surface actions on controlling the basin formation and evolution. The basic dynamic types of basin classification include the prototype basin forming under a single tectonic, thermal, or gravity regime and the superimposed basin as well as residual basin forming under multistage thermal and/or tectonic regimes. Thus, this classification scheme could provide an evolving understanding of lithosphere, crust–mantle interaction, and geodynamic processes as well as of hydrocarbon accumulation and metallogenic mechanisms in sedimentary basins and would help in the synthetic exploration of various resources.

Na0.5Bi0.5TiO3-based ceramic specimens have been extensively investigated as ferroelectric materials. After being doped with CaTiO3, the resulting Na0.5Bi0.5TiO3-based ceramics exhibit relaxor characteristics, and improved energy storage density and efficiency. Based on these above results, CeO2 was further employed to modify the polarization of the 0.85Na0.5Bi0.5TiO3-0.15CaTiO3 matrix ceramic to achieve better energy storage performance. The effective energy storage density was enhanced from 1.93 to 2.53 J/cm3 by using the appropriate doping concentration of CeO2. Grain refinement effect can effectively enhance the electric-field strength from approximately 190 to 230 kV/cm. In particular, when doped with 2% CeO2, the energy storage efficiency of the sample was maintained at approximately 90% at 30 °C-150 °C and at approximately 80% in the frequency range of 0.2–200 Hz. This combination has very excellent temperature stability and frequency stability, making it a promising candidate for energy storage applications.

Background The EXTREME regimen (chemotherapy [CT; cisplatin/carboplatin and 5-fluorouracil]) plus cetuximab is a standard-of-care first-line (1L) treatment for patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN), as supported by international guidelines. The phase III CHANGE-2 trial assessed the efficacy and safety of a modified CT regimen (with a reduced dose of both components) and cetuximab versus CT for the 1L treatment of Chinese patients with R/M SCCHN. Methods Patients were randomised to receive up to six cycles of CT plus cetuximab followed by cetuximab maintenance until progressive disease or CT alone. The primary end-point was the progression-free survival (PFS) time assessed by the independent review committee (IRC). Results Overall, 243 patients were randomised (164 to CT plus cetuximab; 79 to CT). The hazard ratios for PFS by IRC and overall survival (OS) were 0.57 (95% CI: 0.40–0.80; median: 5.5 versus 4.2 months) and 0.69 (95% CI: 0.50–0.93; median: 11.1 versus 8.9 months), respectively, in favour of CT plus cetuximab. The objective response rates (ORR) by IRC were 50.0% and 26.6% with CT plus cetuximab and CT treatment, respectively. Treatment-emergent adverse events of maximum grade 3 or 4 occurred in 61.3% (CT plus cetuximab) and 48.7% (CT) of patients. Conclusions CHANGE-2 showed an improved median PFS, median OS and ORR with the addition of cetuximab to a modified platinum/5-fluorouracil regimen, with no new or unexpected safety findings, thereby confirming CT plus cetuximab as an effective and safe 1L treatment for Chinese patients with R/M SCCHN. Clinical trial registration number NCT02383966.