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In this study, hierarchically mesoporous silica (HMS) with properties such as high specific surface area, high photostability, and no cellular toxicity was synthesized. The synthesized silica can be considered as an excellent carrier candidate material. Through the use of nitrogen adsorption and desorption analysis, the shape of the hysteresis loop implied the presence of mesoporous structures in the HMS powder. In addition, the encapsulation efficiency was more than 90%. These results showed that avobenzone could be encapsulated into the HMS powder because of its high specific surface area and pore volume. Additionally, X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and UV-visible (Vis) spectrophotometry were used to prove that the hierarchically mesoporous silica was able to effectively encapsulate avobenzone. In addition, the new synthetic sunscreen kept its excellent UVA absorption properties after being encapsulated.

This study provides a preparing method for mesoporous silica to effectively encapsulate with avobenzone.  相似文献   
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The treatment of posterior canal benign paroxysmal positional vertigo often involves repositioning maneuvers and exercises; however, these procedures may not be suitable for patients with limb disabilities or back disorders, or for elder patients. We sought to develop a simple therapeutic maneuver as an alternative procedure, suitable for patients with a wide range of physical ability. A simple therapeutic maneuver, supine to prolonged lateral position, was developed based on the mechanism of canalolithiasis. Its efficacy in treating posterior canal benign paroxysmal positional vertigo was evaluated in a prospective study consisting of 81 objective and 13 subjective posterior canal benign paroxysmal positional vertigo patients. A successful outcome was defined as a negative Dix-Hallpike test within 2 weeks followed by the continued absence of symptoms of vertigo or dizziness for the next 4 weeks. Seventy-two patients with objective posterior canal benign paroxysmal positional vertigo and all 13 patients with subjective posterior canal benign paroxysmal positional vertigo were successfully treated: resolution rates were 88.9 and 100 %, respectively. In the objective group, negative Dix-Hallpike tests were obtained at 1 and 2 weeks in 66.7 and 88.9 % of patients, respectively. In the subjective group, the percentages of patients free of side-dependent vertigo illusions at 1 and 2 weeks were 84.6 and 100 %, respectively. These results suggest that the supine to prolonged lateral position maneuver, which is easy to perform and generally well tolerated, could be recommended as an alternative treatment modality for patients with posterior canal benign paroxysmal positional vertigo.  相似文献   
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In contrast to the commonly present UV light-stimulated synaptic oxide thin-film transistors, this study demonstrates a violet light (wavelength of 405 nm) stimulated zinc–tin oxide (ZTO) photoelectric transistor for potential application in optical neuromorphic computation. Owing to the light-induced oxygen vacancy ionization and persistent photoconductivity effect in ZTO, this device well imitates prominent synaptic functions, including photonic potentiation, electric depression, and short-term memory (STM) to long-term memory (LTM) transition. A highly linear and broad dynamic range of photonic potentiation can be achieved by modulating the light power density, while electric depression is realized by gate voltage pulsing. In addition, the brain-like re-learning experience with extended forgetting time (200 s) is well mimicked by the ZTO photoelectric transistor. As a result, the ZTO photoelectric transistor provides excessive synaptic function with multi-series of synaptic weight levels (90 levels for each given light power density), which makes it prevalent in the neuromorphic computation of massive data as well as in learning-driven artificial intelligence computation.

Photonic potentiation and electric depression are realized in a ZTO thin film transistor for the application in neuromorphic computation.  相似文献   
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