Intravesicular Genomic DNA Enriched by Size Exclusion Chromatography Can Enhance Lung Cancer Oncogene Mutation Detection Sensitivity

Extracellular vesicles (EVs) are cell-derived structures surrounded by a lipid bilayer that carry RNA and DNA as potential templates for molecular diagnostics, e.g., in cancer genotyping. While it has been established that DNA templates appear on the outside of EVs, no consensus exists on which nucleic acid species inside small EVs (<200 nm, sEVs) are sufficiently abundant and accessible for developing genotyping protocols. We investigated this by extracting total intravesicular nucleic acid content from sEVs isolated from the conditioned cell medium of the human NCI-H1975 cell line containing the epidermal growth factor (EGFR) gene mutation T790M as a model system for non-small cell lung cancer. We observed that mainly short genomic DNA (<35–100 bp) present in the sEVs served as a template. Using qEV size exclusion chromatography (SEC), significantly lower yield and higher purity of isolated sEV fractions were obtained as compared to exoEasy membrane affinity purification and ultracentrifugation. Nevertheless, we detected the EGFR T790M mutation in the sEVs’ lumen with similar sensitivity using digital PCR. When applying SEC-based sEV separation prior to cell-free DNA extraction on spiked human plasma samples, we found significantly higher mutant allele frequencies as compared to standard cell-free DNA extraction, which in part was due to co-purification of circulating tumor DNA. We conclude that intravesicular genomic DNA can be exploited next to ctDNA to enhance EGFR T790M mutation detection sensitivity by adding a fast and easy-to-use sEV separation method, such as SEC, upstream of standard clinical cell-free DNA workflows.     

Effects of boundary conditions on the end-of-life treatment of LCD TVs

Differences in legislation and markets for recycled materials result in the national implementation of distinct end-of-life treatment strategies. This paper presents a comparative analysis of the boundary conditions in Belgium and Japan that cause the adoption of diverse treatment strategies for the rapidly increasing number of end-of-life flat screen TVs. In addition, both treatment strategies are evaluated from an ecological and economic perspective and opportunities for improvement are identified.     

Efficiency (>15%) for thin‐film epitaxial silicon solar cells on 70 cm2 area offspec silicon substrate using porous silicon segmented mirrors

We report on the beneficial use of embedded segmented porous silicon broad‐band optical reflectors for thin‐film epitaxial silicon solar cells. These reflectors are formed by gradual increase of the spatial period between the layer segments, allowing for an enhanced absorption of low energy photons in the epitaxial layer. By combining these reflectors with well‐established solar cell processing by photolithography, a conversion efficiency of 15·2% was reached on 73 cm² area, highly doped offspec multicrystalline silicon substrates. The corresponding photogenerated current densities (J_sc) were well above 31 mA/cm² for an active layer of only 20 µm. Copyright © 2010 John Wiley & Sons, Ltd.     

Prophid: A Platform-Based Design Method

The continuing trendtowards higher integration densities of integrated circuits makesthe development of systems-on-a-chip possible. For well-definedapplication domains ``silicon platforms' must be defined whichallow efficient, yet programmable implementations. These platformsare heterogeneous reconfigurable multiprocessor architecturessupporting a variety of communication and computation models.As a consequence designers are facing a large architecture spacewith new possibilities for new architectures. To exploit theseopportunities a better understanding of system level architecturesis necessary. A first step in this direction is to learn fromdesign exercises. Eventually this may lead towards a system leveldesign method. In this paper a multiprocessor architecture templateis presented that serves as a platform for high-throughput applications.Central to this architecture is a reconfigurable high-performanceprocessor network that uses communication concepts based on theTST-networks known from the literature. We discuss the characteristicsof the architecture template in detail. Furthermore, we willdiscuss the specification, modelling, and mapping of applicationsfor this architecture. Finally, we analyse cost and performancefigures using real implementation results.     

安特卫普:一座再创造和再度活跃的城市

安特卫普是比利时第二大城市,有着光辉的历史和可预期的未来.早在16世纪,它就是一座重要的城市、主要港口以及国际化的商业与文化中心,许多“佛兰德画派”的著名画家发现这是一个具有创意的空间和适合生活与创作的场所. 安特卫普的发展得益于其位于斯凯尔特河沿岸的优越地理位置:在狭长凹进的河流转弯处的最高点,右岸逐渐发展成天然的船只停泊处.在港口周边,渐渐发展出聚居地,并随着繁忙的港口活动发展成为一座世界级城市.     

Geostatistical reservoir modelling using statistical pattern recognition

The traditional practice of geostatistics for reservoir characterization is limited by the variogram which, as a measure of geological continuity, can capture only two-point statistics. Important curvi-linear geological information, beyond the modelling capabilities of the variogram, can be taken from training images and later used in model construction. Training images can provide multiple-point statistics which describe the statistical relation between multiple spatial locations considered jointly. Stochastic reservoir simulation then consists of anchoring the borrowed geo-structures in the form of multiple-point statistics to the actual subsurface hard and soft data.     

Effects of Low-Thermal-Budget Treatments on the Porous Si Material Properties

Our interest in porous silicon is due to its potential benefits in crystalline Si solar cells. Besides the use as an anti-reflection coating, the porous layer also acts as a light-diffusor. However major drawbacks are the significant light absorption within the porous layer and both insufficient as well as unstable surface passivating capabilities. The unstable nature of the porous Si is also reflected in the presence of suboxides after storage in ambient. In this work we focus on rapid-thermal-oxidation (RTO) and plasma-nitridation as low-thermal-budget chemical modification techniques in order to obtain a surface layer with a controlled and stable structure and composition. RTO of porous Si converts the material into SiO₂ in conjunction with a drastically decreased porosity. Both a remote- and a direct-plasma nitridation of porous Si are able to incorporate nitrogen uniformly throughout the porous layer while preserving the porous character.