β-Ga2O3 cone-like nanowires have been in-situ grown on the surface of gallium grains and films by heating gallium substrates at 750-1000℃for 2h in air.The controllable synthesis ofβ-Ga2O3 nano-wires with different ...β-Ga2O3 cone-like nanowires have been in-situ grown on the surface of gallium grains and films by heating gallium substrates at 750-1000℃for 2h in air.The controllable synthesis ofβ-Ga2O3 nano-wires with different diameters and lengths was achieved by adjusting the heating temperature and time.The as-synthesized products were characterized by means of X-ray diffraction,scanning electron mi-croscopy and transmission electron microscopy.The results showed that theβ-Ga2O3 nanowires are single crystalline with a monoclinic structure and have a controllable diameter and length in the range of 30-100nm and 0.5-1.5μm,respectively.A possible mechanism was also proposed to account for the formation ofβ-Ga2O3 cone-like nanowires.Photoluminescence spectra of theβ-Ga2O3 nanowires obtained at different temperatures were measured at room temperature,and a strong blue photolumi-nescence with peaks at 430 and 460nm and a weak red photoluminescence with peak at 713nm were observed.The blue light emission intensity decreases with increasing the reaction temperature,how-ever,the red light emission intensity hardly changes.The blue and red light emissions originate from the recombination of an electron on an oxygen vacancy with a hole on a gallium-oxygen vacancy pair and the nitrogen dopants,etc.,respectively.展开更多
目的:探究急性大血管闭塞性脑梗死(acute ischemic stroke due to large vessel occlusion,AIS-LVO)机械取栓的预后影响因素,构建列线图模型。方法:选取2020年1月至2023年8月保定市第一中心医院166例AIS-LVO患者,均接受机械取栓,根据取...目的:探究急性大血管闭塞性脑梗死(acute ischemic stroke due to large vessel occlusion,AIS-LVO)机械取栓的预后影响因素,构建列线图模型。方法:选取2020年1月至2023年8月保定市第一中心医院166例AIS-LVO患者,均接受机械取栓,根据取栓后3个月改良Rankin量表评分(modified rankin scale,mRS)分组,比较两组一般资料及血清视锥蛋白样蛋白-1(visininlike protein-1,VILIP-1)、硫氧还蛋白1(thioredoxin-1,Trx1)水平,采用Logistic回归方程、极端梯度提升(extreme gradient boosting,XGBoost)算法对AIS-LVO患者预后的相关因素进行筛选,构建列线图模型,采用受试者工作特征曲线(ROC)及曲线下面积(AUC)分析列线图模型的区分度,采用Bootstrap自抽样法,对数据集进行1000次重抽样的自举验证,进行内部验证并绘制校准曲线,采用决策曲线分析列线图模型的临床有效性。结果:预后不良组血清VILIP-1、入院时美国国立卫生研究院卒中量表(the national institutes of health stroke scale,NIHSS)评分高于预后良好组,Trx1、入院时Alberta卒中项目早期CT(alberta stroke project early CT,ASPECT)评分及CTA评分≥2级比例低于预后良好组(P<0.05);血清VILIP-1、Trx1、CTA评分≥2级及入院时NIHSS评分、ASPECT评分均是AIS-LVO机械取栓预后不良的影响因素(P<0.05);XGBoost算法显示,入院时NIHSS评分的SHAP平均值最高,其次为入院时ASPECT评分、VILIP-1、Trx1及CTA评分≥2级;采用Bootstrap自抽样法对列线图模型进行内部验证,列线图模型的AUCROC为0.927;校准曲线显示,模型的校准曲线观测值和预测值的重合度较好,经Hosmer-Lemeshow优度检验证实预测偏差不存在统计学意义(χ^(2)=5.411,P=0.736);决策曲线显示,列线图模型在0.0~1.0具有明显的正向净收益。结论:联合应用入院时NIHSS评分、ASPECT评分、CTA评分≥2级及血清VILIP-1、Trx1预测AIS-LVO机械取栓预后效能更佳,可帮助临床学者及早识别高危人群,减少预后不良发生。展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.20573072)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20060718010)
文摘β-Ga2O3 cone-like nanowires have been in-situ grown on the surface of gallium grains and films by heating gallium substrates at 750-1000℃for 2h in air.The controllable synthesis ofβ-Ga2O3 nano-wires with different diameters and lengths was achieved by adjusting the heating temperature and time.The as-synthesized products were characterized by means of X-ray diffraction,scanning electron mi-croscopy and transmission electron microscopy.The results showed that theβ-Ga2O3 nanowires are single crystalline with a monoclinic structure and have a controllable diameter and length in the range of 30-100nm and 0.5-1.5μm,respectively.A possible mechanism was also proposed to account for the formation ofβ-Ga2O3 cone-like nanowires.Photoluminescence spectra of theβ-Ga2O3 nanowires obtained at different temperatures were measured at room temperature,and a strong blue photolumi-nescence with peaks at 430 and 460nm and a weak red photoluminescence with peak at 713nm were observed.The blue light emission intensity decreases with increasing the reaction temperature,how-ever,the red light emission intensity hardly changes.The blue and red light emissions originate from the recombination of an electron on an oxygen vacancy with a hole on a gallium-oxygen vacancy pair and the nitrogen dopants,etc.,respectively.
文摘目的:探究急性大血管闭塞性脑梗死(acute ischemic stroke due to large vessel occlusion,AIS-LVO)机械取栓的预后影响因素,构建列线图模型。方法:选取2020年1月至2023年8月保定市第一中心医院166例AIS-LVO患者,均接受机械取栓,根据取栓后3个月改良Rankin量表评分(modified rankin scale,mRS)分组,比较两组一般资料及血清视锥蛋白样蛋白-1(visininlike protein-1,VILIP-1)、硫氧还蛋白1(thioredoxin-1,Trx1)水平,采用Logistic回归方程、极端梯度提升(extreme gradient boosting,XGBoost)算法对AIS-LVO患者预后的相关因素进行筛选,构建列线图模型,采用受试者工作特征曲线(ROC)及曲线下面积(AUC)分析列线图模型的区分度,采用Bootstrap自抽样法,对数据集进行1000次重抽样的自举验证,进行内部验证并绘制校准曲线,采用决策曲线分析列线图模型的临床有效性。结果:预后不良组血清VILIP-1、入院时美国国立卫生研究院卒中量表(the national institutes of health stroke scale,NIHSS)评分高于预后良好组,Trx1、入院时Alberta卒中项目早期CT(alberta stroke project early CT,ASPECT)评分及CTA评分≥2级比例低于预后良好组(P<0.05);血清VILIP-1、Trx1、CTA评分≥2级及入院时NIHSS评分、ASPECT评分均是AIS-LVO机械取栓预后不良的影响因素(P<0.05);XGBoost算法显示,入院时NIHSS评分的SHAP平均值最高,其次为入院时ASPECT评分、VILIP-1、Trx1及CTA评分≥2级;采用Bootstrap自抽样法对列线图模型进行内部验证,列线图模型的AUCROC为0.927;校准曲线显示,模型的校准曲线观测值和预测值的重合度较好,经Hosmer-Lemeshow优度检验证实预测偏差不存在统计学意义(χ^(2)=5.411,P=0.736);决策曲线显示,列线图模型在0.0~1.0具有明显的正向净收益。结论:联合应用入院时NIHSS评分、ASPECT评分、CTA评分≥2级及血清VILIP-1、Trx1预测AIS-LVO机械取栓预后效能更佳,可帮助临床学者及早识别高危人群,减少预后不良发生。
