QUANTUM MECHANICAL MODEL AND SIMULATION OF GaAs/AlGaAs QUANTUM WELL INFRARED PHOTODETECTOR-Ⅱ ELECTRICAL ASPECTS

A complete quantum mechanical model for GaAs/AlGaAs quantum well infrared photodetectors(QWIPs) was presented. The photocurrent was investigated by the optical transition(absorption coefficient)between the ground state and the excited states due to the nonzero component of the radiation field along the sample growth direction. By studying the inter diffusion of the Al atoms across the GaAs/AlGaAs heterointer faces, the mobility of the drift diffusion carriers in the excited states was calculated. As a result, the measurement results of the dark current and the photocurrent spectra are explained theoretically.

QUANTUM MECHANICAL MODEL AND SIMULATION OF GaAs/AlGaAs QUANTUM WELL INFRARED PHOTO-DETECTOR-ⅠOPTICAL ASPECTS

A complete quantum mechanical model for GaAs?AlGaAs quantum well infrared photodetectors(QWIPs) is presented here. The model consisted of four parts: (1) Starting with the description of the electromagnetic field of the infrared radiation in the QWIP, effective component of the vector potential <| A z |> along the QWIP growth direction ( z axis) due to the optical diffraction grating was calculated. (2) From the wave transmissions and the occupations of the electronic states, it was discussed that the dark current in the QWIP is determined by the drift diffusion current of carriers thermally excited from the ground sublevel in the quantum well to extended states above the barrier. (3) The photocurrent was investigated by the optical transition (absorption coefficient between the ground state to excited states due to the nonzero <| A z |> ). (4) By studying the inter diffusion of the Al atoms across the GaAs?AlGaAs heterointerfaces,the mobility of the drift diffusion carriers in the excited states was calculated, so the measurement results of the dark current and photocurrent spectra can be explained theoretically. With the complete quantum mechanical descriptions of (1 4), QWIP device design and optimization are possible.

肝细胞来源外泌体可能成为慢加急性肝衰竭患者肝再生和预后评估的生物标志物

【据Hepatology International 2021年8月报道】题:肝细胞来源外泌体可能成为慢加急性肝衰竭患者肝再生和预后评估的生物标志物(作者Jiao Y等)慢加急性肝衰竭(ACLF)患者虽然肝损伤严重,但是部分患者仍可以通过肝脏再生得以存活,因此ACLF患者的肝再生评估尤为重要。外泌体兼具肝脏活组织检查的特异性和外周血检测的非侵袭性的优点,可能是肝脏疾病潜在的生物标志物。本研究旨在建立ACLF肝再生的外泌体表达谱模型,探讨其在肝衰竭患者肝再生及预后评估中的作用。

骨形态形成蛋白4增强大鼠远端肺动脉平滑肌细胞中的经典瞬间受体离子通道表达和钙池操纵性钙离子内流及基础钙水平

背景和目的：近期研究结果表明骨形态形成蛋白4（BMP4）在肺血管重塑中发挥重要作用，但其作用机制尚不明确。在我们的早期研究中已发现钙离子通过钙池操纵性钙离子通道（SOCC）内流可能是导致慢性缺氧性肺动脉高压的致病因素之一，

肺动脉高压患者气道微生态的组成及改变

背景与目的:肺动脉高压(PH)是一种呈进行性进展的肺血管疾病,其特征为持续性的肺血管收缩、肺血管重塑和原位血栓形成,这种血管病理改变被认为是病情发展的关键因素.近年来有实验研究发现微生态与血管性疾病有密切的联系,同时在肺癌、急性呼吸窘迫综合征、败血症及气道慢性疾病患者中发现气道微生物菌群的改变和全身炎症反应相关,而后者也是肺动脉高压进展的重要原因。

骨髓间充质干细胞移植通过抑制肺血管内皮‐间充质转化治疗肺动脉高压

背景与目的:肺动脉高压(PH)是肺血管阻力和肺动脉压力进行性升高的致命性肺血管疾病,近年来干细胞治疗肺动脉高压得到研究者的关注,但机制未明。本研究旨在探讨骨髓间充质干细胞(MSCs)对肺动脉高压的治疗作用及其对内皮‐间充质转化(EndMT)的潜在调节作用。方法:本研究采用慢性低氧性肺动脉高压(CHPH)大鼠模型和Sugen联合缺氧诱导的PH(SuHx‐PH)大鼠模型两种模型,于缺氧第7天从尾静脉注射骨髓间充质干细胞(细胞数为1×106个);采用肺组织免疫荧光、流式细胞术检测不同时间点用绿色荧光蛋白(GFP)标记的MSCs(GFP+MSCs)在CHPH大鼠肺中的归巢情况;通过血流动力学、肺组织病理学、Masson染色法、免疫荧光、免疫组化、实时荧光定量PCR、免疫蛋白质印迹和羟脯氨酸测定等方法评估MSCs对肺动脉高压大鼠模型的治疗作用及对EndMT的影响。另外培养原代大鼠肺微血管内皮细胞,用MSCs条件培养液(50%v/v)治疗处理,在缺氧72 h后应用免疫荧光、免疫蛋白质印迹、细胞迁移等实验来检测EndMT特异性标志物和细胞迁移特性。

体质量指数、腰围与全因死亡率的关联:一项为期22年的队列研究

该研究通过中国健康与营养调查研究中的一个成年人群研究体质量指数(bodymassindex,BMI)、腰围与全因死亡率的关系。研究者根据世界卫生组织的建议,将该成年人群分为轻体质量(BMI<18.5kg/m^2),正常体质量(BMI18.5~<23.0kg/m^2),超重(BMI23.0~<27.5kg/m^2).肥胖(BMI≥27.5kg/m^2)和腹型肥胖[腰围≥90(男性)、≥80cm(女性)]。结果显示,超重与年龄18~<30岁和30~<40岁男性亚组的全因死亡率降低相关(HR=0.136,0.462;分别P=0.049,0.023),轻体质量与50~59岁和鼻60岁男性亚组的全因死亡率增加相关(分别P=0.007,0.040)。