电子商务与SOA的结合是个真正的机会

面向服务的体系结构（Service-Oriented Architecture,SOA,也叫面向服务架构）是指为了解决在Internet环境下业务集成的需要,通过连接能完成特定任务的独立功能实体实现的一种软件系统架构。SOA是一个组件模型,它将应用程序的不同功能单元（称为服务）通过这些服务之间定义良好的接口和契约联系起来。接口是采用中立的方     

Imaging of KCa3.1 Channels in Tumor Cells with PET and Small-Molecule Fluorescent Probes

The Ca²⁺ activated K⁺ channel K_Ca3.1 is overexpressed in several human tumor cell lines, e. g. clear cell renal carcinoma, prostate cancer, non-small cell lung cancer. Highly aggressive cancer cells use this ion channel for key processes of the metastatic cascade such as migration, extravasation and invasion. Therefore, small molecules, which are able to image this K_Ca3.1 channel in vitro and in vivo represent valuable diagnostic and prognostic tool compounds. The [¹⁸F]fluoroethyltriazolyl substituted senicapoc was used as positron emission tomography (PET) tracer and showed promising properties for imaging of K_Ca3.1 channels in lung adenocarcinoma cells in mice. The novel senicapoc BODIPY conjugates with two F-atoms ( 9 a ) and with a F-atom and a methoxy moiety ( 9 b ) at the B-atom led to the characteristic punctate staining pattern resulting from labeling of single K_Ca3.1 channels in A549-3R cells. This punctate pattern was completely removed by preincubation with an excess of senicapoc confirming the high specificity of K_Ca3.1 labeling. Due to the methoxy moiety at the B-atom and the additional oxyethylene unit in the spacer, 9 b exhibits higher polarity, which improves solubility and handling without reduction of fluorescence quantum yield. Docking studies using a cryo-electron microscopy (EM) structure of the K_Ca3.1 channel confirmed the interaction of 9 a and 9 b with a binding pocket in the channel pore.     

Recent Progress in Developing a LiOH-Based Reversible Nonaqueous Lithium–Air Battery

The realization of practical nonaqueous lithium–air batteries (LABs) calls for novel strategies to address their numerous theoretical and technical challenges. LiOH formation/decomposition has recently been proposed as a promising alternative route to cycling LABs via Li₂O₂. Herein, the progress in developing LiOH-based nonaqueous LABs is reviewed. Various catalytic systems, either soluble or solid-state, that can activate a LiOH-based electrochemistry are compared in detail, with emphasis in providing an updated understanding of the oxygen reduction and evolution reactions in nonaqueous media. We identify the key factors that can switch the cell chemistry between Li₂O₂ and LiOH and highlight the debate around these routes, as well as rationalize potential causes for these opposing opinions. The identities of the reaction intermediates, activity of redox mediators and additives, location of reaction interfaces, causes of parasitic reactions, as well as the effect of CO₂ on the LiOH electrochemistry, all play a critical role in altering the relative rates of a series of interconnected reactions and all warrant further investigation.     

Effects of Lipase Immobilization Conditions and Support Materials for the Production of Structured Triacylglycerols

Structured triacylglycerols (STAG) with desired properties can be synthesized by transesterification using immobilized lipases. Herein, the effect of immobilization conditions and support material on the immobilization yield, specific activity and regioselectivity of lipases from Rhizomucor miehei (RML) and Rhizopus oryzae (ROL) in the production of STAG, are evaluated. Four different support materials utilizing adsorption and one with covalent binding are investigated. Ammonium sulfate is found to significantly increase the activity-based immobilization yield (12% and 38% for RML and ROL, respectively) and specific activity on Accurel MP1000 (MP1000) when used as the immobilization buffer. Furthermore, the immobilization principle and support material influenced both the activity and regiospecificity. Immobilization by adsorption is found to result in higher catalytic activity, while covalent binding resulted in lipase inactivation. For RML, the highest specific activity of 43 µmol STAG min⁻¹ g⁻¹ (U) is obtained on MP1000, while ROL, which exhibited higher activities in general, results in a maximum activity of 120 U on Lifetech ECR8806. The obtained specific activites are comparable to the commercial preparations Novozym 40086 (45 U) and Lipase DF “Amano” IM (147 U) while the regiospecificity of the developed preparations is even higher, forming at least 64% less byproduct. Practical applications: There is an increasing need for lipids with specific nutritional and physical properties in health, nutrition, and food applications. In this context, STAG are highly promising products due to the possibility to tailor the composition to obtain the desired properties. Immobilized lipases are the catalyst of choice for the production of STAG, in which activity and regioselectivity are particularly important parameters for the process performance. In this study, it is shown that these parameters can be affected by the immobilization conditions and support material. Immobilized preparations with high activity and excellent regiospecificity are created on commercially available supports. This shows the possibility of STAG synthesis with high purity and beneficial properties.     

Uncovering microstructure and composition susceptibility of high permittivity ceramic granules to plasma-induced arc breakdown

Effective diversion of surge currents is vital to prevent unwanted damage to sensitive electronics. Among the most successful and efficient strategies relies on a dielectric stimulated arc breakdown mechanism with high permittivity ceramic granules in a spark-gap geometry. Although generally regarded as a self-healing process, substantial energy deposition may occur that, over time, diminishes the ability to withstand repeated electrical assaults. We investigate the susceptibility of lead–magnesium–niobate–lead titanate (PMN–PT) granule microstructure and composition changes following many exposures to high voltage impulses resulting in arc breakdown. Scanning electron microscopy and energy-dispersive spectroscopy mapping reveal a broad range of thermal and mechanical defects entailing thermal reduction of constituent PMN–PT metal ions and recasting due to rapid eruption of volatile species. Additionally, evidence of local melting and microcracking are apparent that can have deleterious impact on the proper function of the granules, namely, the ability to concentrate electric fields across air gaps to establish and sustain discharge pathways. We propose that the localized nature of damage and stochasticity associated with the dielectric stimulated breakdown mechanism may allow granules to maintain functionality provided no permanent conduction paths are established.