Optimal stopping for non-linear expectations—Part II

Relying on the stochastic analysis tools developed in Bayraktar and Yao (2011) [1], we solve the optimal stopping problems for non-linear expectations.     

自动显微镜伺服控制系统的研制

研制了基于AT89C2051单片机的自动显微镜伺服控制系统。该系统采用分布式监控方式,由PC机经RS_232通信接口向单片机发送数据和命令,通过微控制器驱动控制环节和执行环节来实现显微镜载物台在X方向和Y方向上的二维运动(重复精度为±0.02mm),具有自动调焦(精度为0.5μm)和物镜的自动切换功能,能满足与医疗仪器主机配套的要求。该系统的研发不仅为显微镜的自动化作出了贡献,而且也将为提高我国显微镜的水平和行业的技术进步起到促进作用。     

Re-Evaluations of Zr-DFO Complex Coordination Chemistry for the Estimation of Radiochemical Yields and Chelator-to-Antibody Ratios of 89Zr Immune-PET Tracers

(1) Background: Deferoxamine B (DFO) is the most widely used chelator for labeling of zirconium-89 (⁸⁹Zr) to monoclonal antibody (mAb). Despite the remarkable developments of the clinical ⁸⁹Zr-immuno-PET, chemical species and stability constants of the Zr-DFO complexes remain controversial. The aim of this study was to re-evaluate their stability constants by identifying species of Zr-DFO complexes and demonstrate that the stability constants can estimate radiochemical yield (RCY) and chelator-to-antibody ratio (CAR). (2) Methods: Zr-DFO species were determined by UV and ESI-MS spectroscopy. Stability constants and speciation of the Zr-DFO complex were redetermined by potentiometric titration. Complexation inhibition of Zr-DFO by residual impurities was investigated by competition titration. (3) Results: Unknown species, ZrH_qDFO₂, were successfully detected by nano-ESI-Q-MS analysis. We revealed that a dominant specie under radiolabeling condition (pH 7) was ZrHDFO, and its stability constant (logβ₁₁₁) was 49.1 ± 0.3. Competition titration revealed that residual oxalate inhibits Zr-DFO complex formation. RCYs in different oxalate concentration (0.1 and 0.04 mol/L) were estimated to be 86% and >99%, which was in good agreement with reported results (87%, 97%). (4) Conclusion: This study succeeded in obtaining accurate stability constants of Zr-DFO complexes and estimating RCY and CAR from accurate stability constants established in this study.     

Statistical methods and regression analysis of stratospheric ozone and meteorological variables in Isfahan

Data of seven meteorological variables (relative humidity, wet temperature, dry temperature, maximum temperature, minimum temperature, ground temperature and sun radiation time) and ozone values have been used for statistical analysis. Meteorological variables and ozone values were analyzed using both multiple linear regression and principal component methods. Data for the period 1999-2004 are analyzed jointly using both methods. For all periods, temperature dependent variables were highly correlated, but were all negatively correlated with relative humidity. Multiple regression analysis was used to fit the meteorological variables using the meteorological variables as predictors. A variable selection method based on high loading of varimax rotated principal components was used to obtain subsets of the predictor variables to be included in the linear regression model of the meteorological variables. In 1999, 2001 and 2002 one of the meteorological variables was weakly influenced predominantly by the ozone concentrations. However, the model did not predict that the meteorological variables for the year 2000 were not influenced predominantly by the ozone concentrations that point to variation in sun radiation. This could be due to other factors that were not explicitly considered in this study.     

Ein tragbares Gerät für die Füllstandskontrolle

Neben der Füllstandskontrolle mil Radionukliden mittels stationär angebauten Anlagen an Kesseln, Bunkern usw. besteht häufig das Problem der gelegentlichen Füllstandskontrolle an Behältern kleinen Durchmessers. Ein zur Lösung dieser Aufgabe entwickeltes tragbares und nelzunabbängiges Gerät, das nach dem Durchstrahlungsprinzip arbeitet und eine neuartige akustische Anzeige der Füllgrenze aufweist, wird beschrieben. Einige charakteristische Anwendungsmöglichkeiten, wie Füllstandskontrolle in Stahlflaschen und Kabelendverschlüssen, werden erläutert.     

Verbessertes pyrolytisches Aufschlu?verfahren zur Radiostrontiumbestimmung in Reaktorgraphit

Zusammenfassung Eine verbesserte Methode zum raschen oxydativen Aufschluß von Tabletten, Granulat oder Staub aus Reaktorgraphit und Aktivkohle zusammen mit Strontiumträger bei etwa 900°C wird beschrieben. Der Aufschluß wird in einer sehr einfachen Anordnung aus Quarz und Pyrex durchgeführt. Die Probenasche und der Träger werden für die verschiedenen Dekontaminationsverfahren in HCl gelöst. Proben bis etwa 1 g konnten mit Radiostrontiumverlusten von weniger als 5% analysiert werden.Herrn Prof. Dr. H. W. Nürnberg, Direktor des Zentral-instituts für Analytische Chemie, sei für sein Interesse am Fortgang der Arbeiten, der Zentralen Glasbläserei der KFA (Leitung Herr H. Kremer) für die präzise Anfertigung der Quarz- und Pyrexteile, Frl. I. Gröbel und Herrn H. Wehner für technische Hilfe gedankt.     

基于STM32的凝结水液位监控系统的设计与实现

为降低PLC控制单容器液位控制系统的设计难度及成本,本系统选用STM32和STC89C51分别作为上位机与下位机的处理器,设计了基于Modbus-RTU协议的液位监控系统;实现了数据实时采集、显示与报警功能;采用PID算法很好的实现了凝结水液位恒值控制,满足了设计要求;最后给出了系统的实物图和测试结果。实验表明,该系统经济实用,抗干扰能力强,可以在工业控制中广泛使用。     

Beta-decay studies of neutron-rich Sc- Cr nuclei

The neutron-rich nuclei ₂₁^{57, 58}Sc, ₂₂^58-60Ti, ₂₃^60-63V, ₂₄^62-66Cr have been produced at Ganil via interactions of a 61.8A MeV ⁷⁶Ge beam with a ⁵⁸Ni target. Beta-decay studies have been performed using combined - and -ray spectroscopy. Half-lives have been determined and -decay schemes are proposed for ⁵⁸Ti, ⁶¹V and ⁶²Cr. From these studies, new hints for the existence of -decaying isomers in ⁶⁰V and in ⁶²Mn are provided. These results are compared to shell model calculations. The role of the f_7/2- f_5/2 proton-neutron interaction is examined through its influence on the lifetime values.     

Cauchy's equation on Δ+: Further results

Summary In a previous paper [Cauchy's equation on ⁺, Aequationes Math.41 (1991), 192–211], we began the study of Cauchy's equation on ⁺, the space of probability distribution functions of nonnegative random variables. In this paper we continue this study and extend our previous results to triangle functions of the form _{T, L} , whereT is a continuous Archimedean t-norm andL a binary operation onR ⁺, which is iseomorphic to a strict t-conorm. We again use a lattice theoretic approach, and introduce first a theorem on the powers and roots of certain elements of ⁺ under _T,L . Under certain additional restrictions we obtain a representation of sup-continuous solutions, similar to the one found in the first paper.