Evaluation of in vitro stability of large unilamellar liposomes coated with a modified polysaccharide (O-palmitoylpullulan)

Aiming at encapsulation of a hydrosoluble drug, large unilamellar liposomes (LUV) of egg phosphatidylcholine (PC) were coated with a natural polysaccharide derivative, O-palmitoylpullulan (OPP), and its in vitro stability evaluated using fluorescent probes. This coating (in OPP/PC weight ratio of 3) improved significantly the in vitro stability of LUV by decreasing both the permeability and fluidity of the liposomal membrane.This paper was accepted for publication after the 1995 Conference of the European Society of Biomaterials, Oporto, Portugal, 10–13 September.     

基于Patel-Teja状态方程的统一粘度模型(Ⅱ)应用于油气藏流体粘度的预测

基于(I)报根据pVT和Tμp图形的相似性和Patel-Teja状态方程建立的预测纯流体气、液相粘度的统一模型,通过引入常规的状态方程参数的混合规则,将其应用于二元轻烃混合物共计1894个数据点及模拟天然气高压粘度的预测,平均相对误差分别为13.78%和16.75%;应用于油藏原油和天然气高压粘度的预测,结果优于现有的有关油气藏流体粘度模型.     

RF excitation of a flowing gas CO2 waveguide laser

Investigation of an RF excited CO₂ waveguide laser in flowing gas operation is reported. Power extraction of 0.8 W/cm with an efficiency of 10.3% has been achieved. Using W.W. Rigrod's analysis (1965), values of the small-signal gain α₀ and saturation parameter I_s have been determined for different excitation levels and for different pressures of the amplifying medium. The parameters α₀ and I_s, have been determined as 0.6%/cm and 10.4 kW/cm ², respectively, at 125 torr and 100 W/cm³ RF loading power. These values are close to those reported for sealed-off RF CO₂ waveguide lasers with xenon added to the gas mixture     

Influence of mixed-mode loading on fatigue-crack propagation

The subject of fatigue which comprises crack nucleation, crack propagation and final failure or fracture has, over the years, been the subject of numerous theoretical and experimental studies. These studies have highlighted the extrinsic influence of mixed-mode loading in governing the fatigue behavior of a wide spectrum of engineering materials and structures. In this paper we review the basic criteria and models that have been proposed and used to predict crack behavior and response for structures containing large cracks and subject to mixed-mode loading. Since the aspect of crack growth is the focus of this review, the effects or contributions from intrinsic microstructural effects are largely excluded. Specific criteria discussed are the maximum tangential stress, minimum strain-energy density and the maximum energy-release rate criteria. The use of these criteria to predict the behavior of structures is examined based on results published in the open literature. The characteristics and implications of each criterion are examined and discussed with particular relevance to threshold conditions on crack growth, direction of crack growth and crack-growth rate. The limitations of each criterion are highlighted.     

Responses of practicing psychologists to a web site developed to promote empirically supported treatments.

Increased adoption of empirically supported treatments (ESTs) has been hindered in part by inadequate and inconvenient access to EST information and training. To improve diffusion of ESTs, the authors developed a Web application to provide practitioners with concise information by disorder on ESTs. The resulting site, therapyadvisor.com, was evaluated by 239 practicing psychologists to assess the usefulness of the site and explore possible interactions of EST attitudes on ratings of usefulness and impact. Two thirds of participants indicated using ESTs in practice, and limited time and resources were cited as primary barriers to EST adoption. The Web application was rated positively by most participants and was reported to increase awareness of and commitment to try ESTs among approximately 60% of participants. The results of this project support the feasibility of a Web application to increase diffusion and promote further adoption of ESTs. Technological and e-learning advances are promising directions for encouraging the adoption of ESTs specifically and evidence-based practice generally, particularly among busy practitioners who have inadequate time and resources for more traditional forms of dissemination and training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diagnostics and monitoring of complex production processes using measurement of vibration-acoustic signals

A vibration-acoustic method for diagnostics and monitoring of production processes such as cutting metals makes it possible compared with other methods to reduce the requirement for measuring equipment and it provides a computer representation of the results observed. The set of equipment suggested has low cost and it exhibits considerable flexibility compared with existing equipment. __________ Translated from Izmeritel’naya Tekhnika, No. 7, pp. 30–34, July, 2006.     

Technological strategies to improve photostability of a sunscreen agent

Due to the reduction of the ozone layer, there is an increasing need of effective UV protection systems with minimized side-effects. Trans-2-ethylhexyl- p -methoxycinnamate ( trans -EHMC) represents one of the most widely used sunscreen compound. Several studies demonstrated that trans -EHMC is unstable following UV irradiation both in solution and in emulsion formulations. Moreover, various reports of photocontact sensitization induced by trans -EHMC have appeared in the literature. Consequently, in order to ensure adequate efficacy and safety for this sunscreen agent, there is a need for new carrier systems to enhance trans -EHMC photostability. In the present study the photostability of the filter in different formulation types (emulsion–gel, gel and emulsion) with various ingredients is evaluated. In addition, nanoparticles based on poly- D , L -lactide-co-glycolide (PLGA) as carrier for trans -EHMC are investigated. The influence of nanoparticle matrix on the photochemical stability of the sunscreen agent is also presented. The results obtained demonstrated that PLGA nanoparticles are effective in reducing the light-induced degradation of the sunscreen agent. Moreover, the choice of formulation type and the excipients used play an important role in order to obtain a stable cosmetic product containing trans -EHMC.     

Advances in speech transcription at IBM under the DARPA EARS program

This paper describes the technical and system building advances made in IBM's speech recognition technology over the course of the Defense Advanced Research Projects Agency (DARPA) Effective Affordable Reusable Speech-to-Text (EARS) program. At a technical level, these advances include the development of a new form of feature-based minimum phone error training (fMPE), the use of large-scale discriminatively trained full-covariance Gaussian models, the use of septaphone acoustic context in static decoding graphs, and improvements in basic decoding algorithms. At a system building level, the advances include a system architecture based on cross-adaptation and the incorporation of 2100 h of training data in every system component. We present results on English conversational telephony test data from the 2003 and 2004 NIST evaluations. The combination of technical advances and an order of magnitude more training data in 2004 reduced the error rate on the 2003 test set by approximately 21% relative-from 20.4% to 16.1%-over the most accurate system in the 2003 evaluation and produced the most accurate results on the 2004 test sets in every speed category.     

米塔尔钢铁集团的全球并购发展战略

概述了米塔尔的并购经过和并购特点,着重探讨了米塔尔的管理模式、人员情况、钢铁厂布局、生产经营、主要战略伙伴、研发机构及其生产、采购与销售策略。系统地分析了米塔尔在中国的发展,指出米塔尔在全球钢铁业整合中处于领先地位,米塔尔来中国投资看中的是中国的原料和市场,且运作步伐明显加快,会对中国钢铁企业构成很大的威胁。