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Monodisperse hollow silica spheres： An in-depth scattering analysis

Nano Research 2016年第5期9卷 1366-1376页

作者： Pia Ruckdeschel Martin Dulle tobias honold Stephan Forster Matthias Karg Markus Retsch Physical Chemistry 1 - Polymer Systems University ofBayreuth Universitatsstr. 30 95447 Bayreuth Germany Physical Chemistry 1 University of Bayreuth Universitatsstr. 30 95447 Bayreuth Germany Physical Chemistry 1 - Colloidal Systems University of Bayreuth Universitatsstr. 30 95447 Bayreuth Germany

Herein, we fabricate hollow silica nanoparticles with exceptionally narrow size distributions that inherently possess two distinct length scales-tens of nanometers with regards to the shell thickness, and hundreds of nanometers in regards to the total diameter. We characterize these structures using dynamic and static light scattering （DLS and SLS）, small angle X-ray scattering （SAXS）, and transmission electron microscopy （TEM）, and we demonstrate quantitative agreement among all methods. The ratio between the radius of gyration （SLS） and hydrodynamic radius （DLS） in these particles equals almost unity, corresponding to ideal capsule behavior. We are able to resolve up to 20 diffraction orders of the hollow sphere form factor in SAXS, indicating a narrow size distribution. Data from light and X-ray scattering can be combined to a master curve covering a q-range of four orders of magnitude assessing all hierarchical length scales of the form factor. The measured SLS intensity profiles noticeably change when the scattering contrast between the interior and exterior is altered, whereas the SAXS intensity profiles do not show any significant change. Tight control of the aforementioned length scales in one simple and robust colloidal building block renders these particles suitable as future calibration standards.

关键词： hollow sphere silica nanoparticle small angle X-ray scattering light scattering nanoscale characterization

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The maximal size of 6-and 7-arcs in projective Hjelmslev planes over chain rings of order 9 Dedicated to Professor Feng Keqin on the Occasion of his 70th Birthday

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Science China Mathematics 2012年第1期55卷 73-92页

作者： honold Thomas KIERMAIER Michael Department of Information and Electronic Engineering Zhejiang University Mathematisches Institut Universita¨t Bayreuth

We complete the determination of the maximum sizes of (k,n)-arcs,n≤12,in the projective Hjelmslev planes over the two (proper) chain rings Z 9=Z/9Z and S 3=F 3 [X]/(X 2) of order 9 by resolving the hitherto open cases n=6 and n=*** of our proofs rely on decidedly geometric properties of the planes such as Desargues' theorem and the existence of certain subplanes.

关键词：最大规模飞机投射链环生日笛沙格定理最大尺寸几何性质

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Assessment of Chronic Stress： Comparison of Hair Biomarkers and Allostatic Load Indices

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Psychology Research 2014年第7期4卷 517-524页

作者： Pia-Maria Wippert J. honold V. Wang C. Kirschbaum University of Potsdam Potsdam Germany Technical University of Dresden Dresden Germany

Background: The measurement of long-term stress is challenging and depends on the population under study. New methods, such as hair markers or ALIs (allostatic load indices), hold promise as a means of assessing personal stress levels. These methods are relatively new and there is still a lack of knowledge concerning their validity and reliability. Objective: This preliminary study aims to determine the test-retest reliability of hair hormone levels (progesterone, cortisol, dehydroepiandrosteron) and two different ALIs as well as the comparability of these biomarker sets among themselves and with different psychometric measures. Methods: Psychometric and physiological data were collected from 13 participants (10 f, 3 m; age = 28.2 ± 2.1 yr.) on two consecutive days with an interval of 24 hours. An 18-biomarker ALI included: HbA1c (glycosylated hemoglobin), fasting glucose, insulin resistance, triglycerides, HDL (high-density lipoprotein), LDL (low-density lipoprotein) waist-hip ratio, BMI (body mass index), BPSYS (systolic blood pressure), BPDIA (diastolic blood pressure), resting pulse, DHEA-S (dehydroepiandrosteron-serum), cortisol, epinephrine, norepinephrine (12 h urine), CRP (C-reactive protein), sICAM-1 (soluble intracellular adhesion molecule-1) and e-Selectin. ALI-HPA included only cortisol and DHEA-S. Hair samples (3 cm) were analyzed using high-performance LC-MS/MS (liquid chromatography-mass spectrometry). Subjective stress was documented using TICS (the Trier Inventory of Chronic Stress). Descriptive statistics were quantified as means ± SD and correlations with Pearson"s correlation coefficient. For reliability, ICC (inter-class correlation) 2.1 and Bland-Altman analysis (LoA (limits of agreement) 2.00*SD) were calculated. Results: HCC (Hair cortisol concentrations) and ALIs showed high test-retest reliabilities while other hair hormones (i. e., DHEA, progesterone) were only moderate or good in this respect. ALI and HCC correlated moderately, as did hai

关键词：生物标记负荷指标评估慢性 Pearson相关系数应激细胞间粘附分子-1 脱氢表雄酮

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心肌梗死后经冠状动脉祖细胞移植

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世界核心医学期刊文摘（心脏病学分册） 2007年第3期3卷 13-13页

作者： Assmus B. honold J. Schchinger V. A.M. Zeiher 郭俊 Dr.Department of Medicine III J.W. Goethe University Theodor-Stern-Kai 7 60590 Frankfurt Germany

背景:初步研究提示,冠状动脉内移植骨髓(BMC)源性或循环血(CPC)源性祖细胞可改善急性心肌梗死后的左室功能。细胞移植对心肌梗死已治愈患者有何效果尚不知晓。方法:在包括17例患者的最初试验后,在一项对照交叉研究中随机分配75例有既往... 详细信息

背景:初步研究提示,冠状动脉内移植骨髓(BMC)源性或循环血(CPC)源性祖细胞可改善急性心肌梗死后的左室功能。细胞移植对心肌梗死已治愈患者有何效果尚不知晓。方法:在包括17例患者的最初试验后,在一项对照交叉研究中随机分配75例有既往心肌梗死病史(至少已3个月)的稳定性缺血性心脏病患者接受无细胞注射治疗(23例患者)抑或CPC(24例患者)或BMC(28例患者)注射入供应左室运动障碍最严重区域的开放冠状动脉。

关键词：祖细胞缺血性心脏病左室功能细胞移植循环血交叉研究射血分数后左室运动障碍随机分配

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心血管磁共振成像评估主动脉狭窄与常规临床检查技术的比较

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世界核心医学期刊文摘（心脏病学分册） 2005年第1期1卷 22-22页

作者： Kupfahl C. honold M. Meinhardt G. U. Sechtem 艾文婷 Department of Cardiol ogy Robert Bosch Medical Centre Auerbachstrasse 110 70376 Stuttgart GermanyDr.

Objective: To evaluate whether direct planimetry of aortic valve area ( AVA) by cardiac magnetic resonance (CMR) imaging is a reliable tool for determining the severity of aortic stenosis compared with transthoracic echocardiography (TTE), transoesophageal echocardiography (TOE), and cardiac catheterisation. Methods: 44 symptomatic patients with severe aortic stenosis were studied. By cardiac cat heterisation AVA was calculated by the Gorlin equation. AVA was measured with CM R from steady state free precession (true fast imaging with steady state precess ion) by planimetry. AVA was also determined from TOE images by planimetry and fr om TTE images by the continuity equation. Results: Bland-Altman analysis evalua ting intraobserver and interobserver variability showed a very small bias for bo th (-0.016 and 0.019, respectively; n=20). Bias and limits of agreement between CMR and TTE were 0.05 (-0.35, 0.44) cm2 (n=37), between CMR and TOE 0.02 (-0. 39, 0.42) cm2 (n=32), and between CMR and cardiac catheterisation 0.09 (-0.30, 0.47) cm2 (n=36). The sensitivity and specificity of CMR to detect AVA ≤0.80 cm 2 measured by cardiac catheterisation was 78%and 89%, of TOE 70%and 70%, and of TTE 74%and 67%, respectively. Conclusion: CMR planimetry is highly reliabl e and reproducible. Further,CMR planimetry had the best sensitivity and specific ity of all non-invasive methods for detecting severe aortic stenosis in compari son with cardiac catheterisation. Therefore, CMR planimetry of AVA with steady s tate free precession is a new powerful diagnostic tool,particularly for patients with uncertain or discrepant findings by other modalities.

关键词：磁共振成像主动脉狭窄主动脉瓣口面积经胸超声心动图可重复性特异度心导管旋进连续方程诊断技术

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