Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrome...Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.展开更多
Honeycomb interlayer structure sound wave transferring theory of infinite is introduced into the underwater noise control. Based on the layered elastic or viscoelastic medium, the sound insulation property of a normal...Honeycomb interlayer structure sound wave transferring theory of infinite is introduced into the underwater noise control. Based on the layered elastic or viscoelastic medium, the sound insulation property of a normal incidence plane wave on underwater honeycomb interlayer structure is studied by using the method of the transfer matrix and percentage distribution of sound energy in As a particular kind of complex multilayered rubber compound structures, honeycomb different areas. compound structure has better sound insulation property than rubber interlayer with cylindrical cavities compound structure. Simulation results show that the property of rubber material has great effect on structural sound insulation. Soft and small Poisson＇ s ratio rubber can obviously improve sound insulation performance of the whole structure. Furthermore, the material property of the face layer of the honeycomb interlayer structure has greater effects on the insulation performance. To validate the theoretical analysis, large samples of freedom-field measurement of honeycomb sandwich compound structure is carried out in the anechoic water tank of our university. The measurement result is in good agreement with the theoretical prediction.展开更多
目的:探讨多元复合声治疗联合口服银杏叶提取物在治疗慢性主观性耳鸣患者中的效果与安全性。方法:选取我院2021年2月至2024年2月收治的60例慢性主观性耳鸣患者作为研究对象,采用随机数字表法分为单一组和联合组,各30例。单一组患者接受...目的:探讨多元复合声治疗联合口服银杏叶提取物在治疗慢性主观性耳鸣患者中的效果与安全性。方法:选取我院2021年2月至2024年2月收治的60例慢性主观性耳鸣患者作为研究对象,采用随机数字表法分为单一组和联合组,各30例。单一组患者接受多元复合声治疗,联合组在单一组的基础上增加口服银杏叶提取物治疗。分别评估两组患者的临床疗效、听力损失程度、耳鸣改善情况[耳鸣严重程度分级量表(Tinnitus Handicap Inventory,THI)]、生活质量[健康状况调查量表(36-Item Short Form Health Survey,SF-36)]、睡眠质量[匹兹堡睡眠质量指数(Pittsburgh Sleep Quality Index,PSQI)]和心理状态[贝克焦虑量表(Beck Anxiety Inventory,BAI)]。结果:联用组的临床总有效率明显高于单一组(P<0.05);治疗后,两组患者的听力损失程度和THI评分、PSQI、BAI评分均明显降低,且联用组明显低于单一组(P<0.05);两组患者的SF-36评分均明显升高,且联用组明显高于单一组(P<0.05)。结论:多元复合声治疗联合口服银杏叶提取物治疗慢性主观性耳鸣患者临床疗效好,可以有效降低听力损伤程度,改善患者的耳鸣症状,提高其生活质量和睡眠质量,促进心理健康。展开更多
DIVA(Directions Into Velocities of Articulators)模型是一种被用来对涉及大脑中有关语音生成和理解区域的功能进行仿真和描述的自适应神经网络模型,其依赖的语言背景是英文29个基本音素。由于汉语与英语发音区别很大,且加工脑机制也...DIVA(Directions Into Velocities of Articulators)模型是一种被用来对涉及大脑中有关语音生成和理解区域的功能进行仿真和描述的自适应神经网络模型,其依赖的语言背景是英文29个基本音素。由于汉语与英语发音区别很大,且加工脑机制也颇为不同,要想将汉语者大脑思维过程"阅读"出来,需要对模型汉语背景的适应性进行专门研究。在DIVA模型的基础上研究汉语复合元音的发音方法,探讨汉语者脑区语音生成与获取的相关问题。通过调节模型的共振峰以及模拟声道对应器官的参数,新构建的模型能很好地辨识汉语与英语元音的区别。该研究为DIVA模型汉语语音生成与获取奠定了良好的基础。展开更多
文摘Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.
基金supported by the 985-2(New Century Excellent Scholar Plan)Project under Grant No.NCET-04-0959
文摘Honeycomb interlayer structure sound wave transferring theory of infinite is introduced into the underwater noise control. Based on the layered elastic or viscoelastic medium, the sound insulation property of a normal incidence plane wave on underwater honeycomb interlayer structure is studied by using the method of the transfer matrix and percentage distribution of sound energy in As a particular kind of complex multilayered rubber compound structures, honeycomb different areas. compound structure has better sound insulation property than rubber interlayer with cylindrical cavities compound structure. Simulation results show that the property of rubber material has great effect on structural sound insulation. Soft and small Poisson＇ s ratio rubber can obviously improve sound insulation performance of the whole structure. Furthermore, the material property of the face layer of the honeycomb interlayer structure has greater effects on the insulation performance. To validate the theoretical analysis, large samples of freedom-field measurement of honeycomb sandwich compound structure is carried out in the anechoic water tank of our university. The measurement result is in good agreement with the theoretical prediction.
文摘目的:探讨多元复合声治疗联合口服银杏叶提取物在治疗慢性主观性耳鸣患者中的效果与安全性。方法:选取我院2021年2月至2024年2月收治的60例慢性主观性耳鸣患者作为研究对象,采用随机数字表法分为单一组和联合组,各30例。单一组患者接受多元复合声治疗,联合组在单一组的基础上增加口服银杏叶提取物治疗。分别评估两组患者的临床疗效、听力损失程度、耳鸣改善情况[耳鸣严重程度分级量表(Tinnitus Handicap Inventory,THI)]、生活质量[健康状况调查量表(36-Item Short Form Health Survey,SF-36)]、睡眠质量[匹兹堡睡眠质量指数(Pittsburgh Sleep Quality Index,PSQI)]和心理状态[贝克焦虑量表(Beck Anxiety Inventory,BAI)]。结果:联用组的临床总有效率明显高于单一组(P<0.05);治疗后,两组患者的听力损失程度和THI评分、PSQI、BAI评分均明显降低,且联用组明显低于单一组(P<0.05);两组患者的SF-36评分均明显升高,且联用组明显高于单一组(P<0.05)。结论:多元复合声治疗联合口服银杏叶提取物治疗慢性主观性耳鸣患者临床疗效好,可以有效降低听力损伤程度,改善患者的耳鸣症状,提高其生活质量和睡眠质量,促进心理健康。
文摘DIVA(Directions Into Velocities of Articulators)模型是一种被用来对涉及大脑中有关语音生成和理解区域的功能进行仿真和描述的自适应神经网络模型,其依赖的语言背景是英文29个基本音素。由于汉语与英语发音区别很大,且加工脑机制也颇为不同,要想将汉语者大脑思维过程"阅读"出来,需要对模型汉语背景的适应性进行专门研究。在DIVA模型的基础上研究汉语复合元音的发音方法,探讨汉语者脑区语音生成与获取的相关问题。通过调节模型的共振峰以及模拟声道对应器官的参数,新构建的模型能很好地辨识汉语与英语元音的区别。该研究为DIVA模型汉语语音生成与获取奠定了良好的基础。
基金Supported by the Chinese National ScienceFoundationSupported by the National Excellent Ph.DSupported by the the Graduate Starting Seed Fund of Northwestern Polytechnical University.
