Suchergebnisse

Abstract. Real-time probabilistic seismic hazard assessment (PSHA) was developed in this study in consideration of its practicability for daily life and the rate of seismic activity with time. Real-time PSHA follows the traditional PSHA framework, but the statistic occurrence rate is substituted by time-dependent seismic source probability. Over the last decade, the pattern informatics (PI) method has been developed as a time-dependent probability model of seismic source. We employed this method as a function of time-dependent seismic source probability, and we selected two major earthquakes in Taiwan as examples to explore real-time PSHA. These are the Meinong earthquake (ML 6.6) of 5 February 2016 and the Hualien earthquake (ML 6.2) of 6 February 2018. The seismic intensity maps produced by the real-time PSHA method facilitated the forecast of the maximum expected seismic intensity for the following 90 d. Compared with real ground motion data from the P-alert network, our seismic intensity forecasting maps showed considerable effectiveness. This result indicated that real-time PSHA is practicable and provides useful information that could be employed in the prevention of earthquake disasters.

The outcome of limb salvage treatment for femoral osteosarcoma with pathological fractures in children is currently unknown. The aim of the present study was to present two cases of patients who received limb salvage surgery with preservation of the epiphysis at the Department of Orthopedics of The General Hospital of Jinan Military Commanding Region (Shandong, China). Between January, 2007 and January, 2013, two pediatric patients were admitted to our hospital with pathological fractures. One of the patients was a girl, aged 11 years, with confirmed osteosarcoma of the right distal femur; the other patient was a boy, aged 9 years, with osteosarcoma of the left distal femur. After receiving two cycles of neoadjuvant chemotherapy following tumor biopsy, the patients received limb salvage surgery with epiphyseal preservation, with wide resection of the tumor and biological reconstruction by allogeneic bone and fibular autograft, followed by 10 cycles of adjuvant chemotherapy. With a mean follow-up of 64 months, there were no postoperative complications, local recurrence or metastasis. The limb function recovered well, although limb shortening was observed. The female patient underwent a second fixation and limb lengthening after epiphyseal closure. Therefore, with effective neoadjuvant chemotherapy, limb salvage surgery with epiphyseal preservation is not contraindicated for pediatric patients with pathological fractures from femoral osteosarcoma. Biological reconstruction by allogeneic bone and vascularized fibular autograft following wide tumor resection is a viable option for such patients, with a good postoperative functional outcome.

In this study, binary SiO2-CaO hollow mesoporous bioactive glass nanoparticles (HMBGNs) are prepared by combing selective etching and impregnation strategies. Spherical silica particles (SiO2 NPs) are used as hard cores to assemble cetyltrimethylammonium bromide (CTAB)/silica shells, which are later removed by selective etching to generate a hollow structure. After the removal of CTAB by calcination, the mesoporous shell of particles is formed. Calcium (Ca) is incorporated into the particles using impregnation by soaking the etched SiO2 NPs in calcium nitrate aqueous solution. The amount of incorporated Ca is tailorable by controlling the ratio of SiO2 NPs:calcium nitrate in the soaking solution. The produced HMBGNs are bioactive, as indicated by the rapid formation of hydroxyapatite on their surfaces after immersion in simulated body fluid. In a direct culture with MC3T3-E1 cells, HMBGNs were shown to exhibit concentration-dependent cytotoxicity and can stimulate osteogenic differentiation of MC3T3-E1 cells at concentrations of 1, 0.5, and 0.25 mg/mL. Our results indicate that the combination of selective etching and impregnation is a feasible approach to produce hierarchical HMBGNs. The produced hollow particles have potential in drug delivery and bone tissue regeneration applications, and should be further investigated in detailed in vitro and in vivo studies. ; European Union's Horizon 2020 research and innovation program 685872-MOZART