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Langerhans cell histiocytosis (LCH) is a neoplastic disease characterized by aberrant proliferation of the mononuclear phagocyte system, predominantly affecting children under the age of 3 years. Although LCH can affect almost all organs, sinus involvement is rare. This case report documents a 9-year-old boy presented with vision impairment and intermittent headache on the right side. The CT scan and MRI examination revealed the presence of a soft mass in the right atrium of sphenoid sinus, which impacted the right optic canal. Biopsy results confirmed the presence of LCH. Considering the involvement of optic canal and vision impairment, meticulous debridement was performed followed by a 12-month standard chemotherapy. After 2 years of follow-up, the patient showed significant improvement, despite the presence of an encapsulated cyst in the right sphenoid sinus. This case highlights the importance of considering LCH when encountering an isolated soft mass accompanied by decreased vision in the sphenoid sinus. A thorough physical examination, laboratory tests, and imaging methods should be performed, with a biopsy being necessary to confirm the type of lesion and guide the appropriate treatment.

MgH2, TiH2, and ZrH2are three typical metal hydrides that have been gradually applied to composite explosives and propellants as additives in recent years. To evaluate ignition sensitivity and explosion severity, the Hartmann device and spherical pressure vessel were used to test ignition energy and explosion pressure, respectively. The results showed that the ignition sensitivity of ZrH2, TiH2and MgH2gradually increased. When the concentration of MgH2is 83.0 g/m3in Hartmann device, the ignition energy attained a minimum of 10.0 mJ. The explosion pressure of MgH2were 1.44 times and 1.76 times that of TiH2and ZrH2, respectively, and the explosion pressure rising rate were 3.97 times and 9.96 times that of TiH2and ZrH2, respectively, through the spherical pressure vessel. It indicated that the reaction reactivity and reaction rate of MgH2were higher than that of TiH2and ZrH2. In addition, to conduct in–depth theoretical analysis of ignition sensitivity and explosion severity, gas production and combustion heat per unit mass of ZrH2, TiH2and MgH2were tested by mercury manometer and oxygen bomb calorimetry. The experimental results revealed that MgH2had a relatively high gas production per unit mass (5.15 mL/g), while TiH2and ZrH2both had a gas production of less than 2.0 mL/g. Their thermal stability gradually increased, leading to a gradual increase in ignition energy. Furthermore, compared with theoretical combustion heat, the combustion ratio of MgH2, TiH2and ZrH2was more than 96.0%, with combustion heat value of 29.96, 20.94 and 12.22 MJ/kg, respectively, which was consistent with the explosion pressure and explosion severity test results.

The article studies the development and effects of the sport ability index on the physique-ability training and preparations of female Chinese taekwondo athletes for the 2008 Beijing Olympics. It includes an in-depth analysis of the index system indicative of the sports abilities of the athletes, as well as a discussion on the issues' implications for sports training and science.