Biological variations of ADAMTS13 and von Willebrand factor in human adults

Background:

The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.

Materials and methods:

Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.

Results:

The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.

Conclusion:

We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels.     

以频率估计概率的误差估计及其应用

阐述了以频率估计概率的误差估计公式，并举例说明公式在实际问题中的有关应用。     

Datenstrukturen visualisieren und animieren mit DDD

Zusammenfassung. Der graphische Debugger DDD ist mit mehr als 250.000 Anwendern ein weitverbreitetes Werkzeug zur Softwarevisualisierung. Neben der für Debuggerüblichen Funktionalit?t erm?glicht DDD die Visualisierung von Datenstrukturen im laufenden Programm. DDD kann verzeigerte Strukturen (wie Listen oder B?ume) als Graphen darstellen, aber auch numerische Felder zwei- oder dreidimensional darstellen und im Programmlauf animieren. Dieser Beitrag beschreibt die technischen Grundlagen der Visualisierung, die verwendeten Plazierungsverfahren und die Animation von Algorithmen. Eingegangen am 13. Oktober 2000 / Angenommen am 19. Dezember 2000     

部分泛von Staudt定理的简化证明

运用p-adic赋值理论给出了泛可除Bernoulli数B^An／n的系数τu的p—adic赋值的界,从而给出了泛von Staudt定理中部分同余式的简化证明．     

Praxisleitfaden zur Betreuung von Diplomarbeiten

Die vorliegende Arbeit beschreibt erfolgskritische Faktoren des bei der Erstellung von Diplomarbeiten zwischen Studenten und Gutachter bestehenden Betreuungsverh?ltnisses und soll praktische Hinweise zu dessen Optimierung liefern.     

Stichwort: Bildungsökonomie und Qualität der Schulbildung

Keyword: Education Economics and Quality of Schooling. With reference to an earlier keyword article from the same author, this contribution looks at recent developments in education economics. The focus is a critical review of the field‘s contribution to research on the necessary conditions for high quality schooling. Of particular interest at the moment are the institutional framework conditions in a school system, which set incentives for performance. These are judged to be better than resource-based strategies of quality assurance. The empirical basis is provided by estimates of production functions using data from international school performance studies. This article will point out the limited validity of evidence gained through these studies and the – in sum – contradictory empirical findings. For this reason, political recommendations on the basis of this approach should be more reserved.     

20世纪德国高等教育改革及其当代启示

洪堡传统是德国高等教育的基石,其基本的理念是学术修养与精英教育。但是这一传统在面临新的情况时出现了种种问题,在恪守传统与寻求变革之间,德国人试图找出可以平衡二者的方法,即在精英教育与职业教育之间寻求妥协。当下中国的高等教育也存在着诸多弊病,其中最突出的问题之一就是大学生的就业难问题。在解决这个问题之前,我们首先应当明确的是,大学教育应偏重于精英化即培养大师,还是应当往职业化的方向发展即为劳动力市场培养具备职业技能的合格劳动者。但是问题在于,我们的大学既未能培养出真正的大师,也没能训练出适应社会需要的具备职业技能的合格劳动者。德国的高等教育发展也经历过与我们同样的问题,因此研究其解决这些问题的方法必定能够为我们带来一些有益的启示。     

Hierarchical models for failure analysis of plates bent by distributed and localized transverse loadings

The failure analysis of simply supported, isotropic, square plates is addressed. Attention focuses on minimum failure load amplitudes and failure locations, von Mises＇ equivalent stress along the plate thickness is also addressed. Several distributed and localized loading conditions are considered. Loads act on the top of the plate. Bi-sinusoidal and uniform loads are taken into account for distributed loadings, while stepwise constant centric and off-centric loadings are addressed in the case of localized loadings. Analysis is performed considering plates whose length-to-thickness ratio a/h can be as high as 100 （thin plates） and as low as 2 （very thick plates）. Results are obtained via several 2D plate models. Classical theories （CTs） and higher order models are applied. Those theories are based on polynomial approximation of the displacement field. Among the higher order theories （HOTs） HOTsa models account for the transverse shear deformations, while HOTs models account for both transverse shear and transverse normal deformations. LHOTs represent a local application of the higher order theories. A layerwise approach is thus assumed： by means of mathematical interfaces, the plate is considered to be made of several fictitious layers. The exact 3D solution is presented in order to determine the accuracy of the results obtained via the 2D models. In this way a hierarchy among the 2D theories is established. CTs provide highly accurate results for a/h greater than 10 in the case of distributed loadings and greater than 20 for localized loadings. Results obtained via HOTs are highly accurate in the case of very thick plates for bi-sinusoidal and centric loadings. In the case of uniform and off-centric loadings a high gradient is present in the neighborhood of the plate top. In those cases, LHOTs yield results that match the exact solution.     

试论米塞斯经济学方法论的历史线索

奥地利经济学派新与自由主义经济学重要代表人物米塞斯以其行动学方法论而著称,其行动学体系有着一条理性主义的演绎逻辑红线,其中方法论个人主义是其基本点。通过对历史主义、实证主义方法论以及方法论整体主义的反思与批判,米塞斯的方法论学说为经济学方法论作出了重要贡献。通过对米塞斯行动学方法论的比较式学理研究,有助于更深刻理解和把握现代经济学思潮的发展义理。