祁连山东部大气降水分δ17O变化特征及水汽输送          下载免费PDF全文

马兴刚  贾文雄  丁丹  朱国锋  巩宁刚  徐秀婷  袁瑞丰 《干旱区地理》2019,42(3):517-525

祁连山作为我国西部重要生态安全屏障,是河西走廊内陆河流域核心水源区。通过测定2013年7月~2014年7月收集的降水样品中δ¹⁷O与δ¹⁷O值,分析了祁连山东部乌鞘岭大气降水中δ¹⁷O的特征,在此基础上对水汽来源进行了研究。结果表明：降水稳定同位素¹⁷O存在夏高冬低的变化特征;¹⁷O存在显著的温度效应而不存在降水量效应,¹⁷O与水汽压在干季呈现正相关关系。研究区大气降水的氧同位素降水线方程为：δ′¹⁷O = 0.509δ′¹⁷O -0.16,低于氧同位素全球降水线斜率;过量δ¹⁷O表现出夏低冬高的特点;综合分析氧同位素大气降水方程线和过量δ¹⁷O变化,发现该区域大气降水主要受局地水循环和大陆气团控制。祁连山东部地区主要受到西风和东南季风携带水汽影响,东南季风携带水汽对于祁连山东部的影响主要集中于夏季。研究可提高对祁连山区降水同位素演化的认知,为寒旱区同位素水文学的进一步研究奠定基础。  相似文献   

iTRAQ-based analysis of 17β-estradiol induced proteome in Chinese tongue sole Cynoglossus semilaevis     

ZHU Ying  LI Yangzhen  LI Hailong  WANG Lei  ZHANG Ning  LIU Yang  MENG Liang  XU Xiwen  DONG Zhongdian  WEI Min  GUO Hua  CUI Zhongkai  LI Xihong  SHAO Changwei  XU Wenteng 《海洋湖沼学报（英文）》2019,(5):1659-1668

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健脾祛湿颗粒联合卡泊三醇软膏治疗银屑病湿热蕴阻证50例          下载免费PDF全文

刘少芬  郭岱炯  杨玉峰 《应用海洋学学报》2023,39(11):8

目的:观察健脾祛湿颗粒联合卡泊三醇软膏治疗银屑病湿热蕴阻证的临床疗效,以及对患者血清白细胞介素-17（IL-17）、白细胞介素-23（IL-23）水平的影响。方法:选取银屑病湿热蕴阻证患者150 例,采用随机数字表法将其分为治疗组、对照1组及对照2组,每组各50 例。对照1组采用外涂卡泊三醇软膏联合口服复方甘草酸苷片治疗,对照2组采用外涂卡泊三醇软膏治疗,治疗组在对照组2组的基础上加服健脾祛湿颗粒,3组均治疗8周。比较3组治疗前、治疗4 周、治疗8 周后银屑病皮损面积与严重指数（PASI）评分、皮肤病生活质量指数（DLQI）评分及血清IL-17、IL-23水平,并进行安全性评价,于治疗结束后第 4 周随访复发情况。结果：总有效率治疗组为96.00%（48/50）,高于对照1组的92.00%(46/50)及对照2组的82.00%(41/50),差异均有统计学意义（P＜0.05）。治疗4周后及8周后,3组PASI、DLQI评分及血清IL-17、IL-23水平均较治疗前下降,且治疗后同时间节点治疗组均优于对照1、2组（P＜0.05）。治疗过程中,3组均未出现明显不良反应。复发率治疗组低于对照1、2组（P＜0.05）。结论：健脾祛湿颗粒联合卡泊三醇软膏治疗银屑病湿热蕴阻证疗效显著,能改善患者临床症状,降低患者PASI、DLQI评分以及血清IL-17、IL-23水平,且无明显不良反应,复发率亦较低,值得临床推广应用。  相似文献   

利用核酸适配体修饰氧化石墨烯复合物的17β-雌二醇检测机理     

朴云仙  胡慧  姚兰  张彧  梁丽娜  刘再冉 《吉林大学学报(地球科学版)》2020,50(4):1189-1196

为了提高复杂环境水体中雌激素污染的检测性能,通过直接吸附法将核酸适配体固定在氧化石墨烯表面,合成出核酸适配体修饰氧化石墨烯复合物,并将其应用于17β-雌二醇水体污染的高灵敏和特异性均相检测。采用紫外可见分光光谱分析核酸适配体修饰氧化石墨烯复合物,发现该复合物在250 nm处有较宽的肩峰,证明核酸适配体成功固定在氧化石墨烯表面。通过荧光分光光度计分析核酸适配体修饰氧化石墨烯复合物与目标物17β-雌二醇反应前后的荧光强度变化,发现荧光强度由峰值110增加到峰值450,表明该复合物可以成功用于对17β-雌二醇的检测,并且荧光强度与17β-雌二醇的质量浓度在10~100 μg/L范围内呈正比,最低检出限为6.2 μg/L。  相似文献   

General polytropic spheres as gravitational lenses     

《New Astronomy》2024

We propose hydrostatic polytropic spheres governed by the Lane-Emden equation (LEE) of index $n$ as a novel set of physical models for axially averaged gravitational lenses anywhere in the Universe, alternative to the familiar singular isothermal sphere (SIS) and the Navarro–Frenk–White (NFW) profile, as such general polytropic spheres are conceptually simple, versatile in representing a series of equations of state, and able to address both the inner core and cusp features. As LEE is nonlinear, there exist several distinct classes of LEE solutions to serve as physical lens models. With a few scaling parameters, the complete problem can be readily reconstructed with full physical dimensions. A given mass density profile satisfying LEE produces lensing effects that are solely determined by a dimensionless parameter $q$ which contains geometric and kinematic information about the source-lens-observer system. The lens mapping and tangential shear or distortion profile are derived, first analytically for special cases and then asymptotically at the outskirts or near the edge of the lens. Numerical procedures for calculating full lensing profiles of a general lens are developed. Our results include the analytical “singular polytropic sphere” (SPS) profile which generalizes the SIS model and may outperform the latter in modeling dark matter halos among others. We further point out that dynamic models of general polytropic spheres in self-similar evolution can serve as several broad classes of gravitational lenses and produce time-dependent lensing effects slow or fast depending on the pertinent time scales. Astrophysical sources that can be lensed include electromagnetic wave sources in the entire frequency band, gravitational wave sources in the entire frequency band, gravitons even possibly with finite masses, neutrino sources of three different types, neutron sources, and ultra high energy cosmic rays (UHECRs) of electrically charged particles which can also interact with magnetic fields. We discuss and elabrate applications to dark matter halos, hypermassive black holes and supermassive black holes in the entire Universe including the early Universe, magnetized supermassive stars, static and dynamically evolving spherical and cylindrical lenses in contexts of astrophysics and cosmology.  相似文献