Photocaged Hoechst Enables Subnuclear Visualization and Cell Selective Staining of DNA in vivo

Selective targeting of DNA by means of fluorescent labeling has become a mainstay in the life sciences. While genetic engineering serves as a powerful technique and allows the visualization of nucleic acid by using DNA-targeting fluorescent fusion proteins in a cell-type- and subcellular-specific manner, it relies on the introduction of foreign genes. On the other hand, DNA-binding small fluorescent molecules can be used without genetic engineering, but they are not spatially restricted. Herein, we report a photocaged version of the DNA dye Hoechst33342 (pcHoechst), which can be uncaged by using UV to blue light for the selective staining of chromosomal DNA in subnuclear regions of live cells. Expanding its application to a vertebrate model organism, we demonstrate uncaging in epithelial cells and short-term cell tracking in vivo in zebrafish. We envision pcHoechst as a valuable tool for targeting and interrogating DNA with precise spatiotemporal resolution in living cells and wild-type organisms.     

景观设计展望:国际性和中国特色

中国的当代景观设计仍然在传统的范例和国际的范例之间探寻其自己的风格。北京土人景观规划设计研究院所做的项目展示了当代的、同时又是自己的设计语言,彰显了全球化背景下当代中国人的身份。     

The consequences of an increase in heavy goods vehicles for passenger car drivers' mental workload and behaviour: a simulator study

The effects of an increase in Heavy Goods Vehicles (HGVs) on merging behaviour and on mental workload of motorists during filtering in and out of traffic were studied. Participants drove in a driving simulator in a total of 12 conditions; twice in each of two weather conditions and in three traffic conditions. The weather conditions were clear weather and foggy weather. The traffic conditions were without HGVs (i.e. only private cars), the current mix of HGVs and private cars, and a condition with a 70% increase of HGVs leading to an HGV column in the slow lane. The focus of the study was on assessing effects on behaviour and mental workload during filtering into traffic, and during exiting from the motorway. During the experiment driving performance was registered, behaviour was observed, self reports were collected, and the participant's heart rate was recorded. The results showed that directly after filtering into traffic the variation in driving speed increased and the minimum time headway decreased with an increase in the proportion of HGVs. Joining motorway traffic was considered to involve greater effort and risk in the condition with a column of HGVs. The effects of the conditions on heart rate are less clear, although the moment when the participants joined the traffic is clearly visible. The effects of weather conditions were limited, drivers adapting their driving behaviour in adverse weather by reducing speed. To exit the motorway is not a difficult manoeuvre. For that reason the lane change from the left hand to the right hand lane that preceded the exit was analysed. Although increased mental effort was reported and the lane change was visible in the heart rate record, no critical changes as a result of increase in proportion of HGVs were found for this manoeuvre. However, in the condition with a column of HGVs, the exit that had to be taken was most frequently missed as HGVs obstructed the view of the exit signs. It is concluded that an increase in HGVs will make merging into traffic more mentally demanding and will decrease safety margins.     

高炉炉衬和冷却技术

介绍了达涅利康力斯板式冷却器炉衬和冷却概念,并介绍炉役期已达16年的康力斯IJmuiden6号高炉。在连续生产3430万t铁水之后,最近对这座高炉的炉底和炉缸区进行大修。康力斯IJmuiden6号高炉炉腹上部区、炉腰区和炉身区的设计表现非常好,仅在上述部分看到轻微的侵蚀现象。达涅利康力斯在其他许多高炉上也采用同样的设计,达到很长的炉龄。康力斯IJmuiden6号高炉达到这样长的炉龄,证明了采用具有良好传热性能的耐火材料结合板式冷却器设计,具有很高的可靠性。     

Selection and fusion of color models for image feature detection

The choice of a color model is of great importance for many computer vision algorithms (e.g., feature detection, object recognition, and tracking) as the chosen color model induces the equivalence classes to the actual algorithms. As there are many color models available, the inherent difficulty is how to automatically select a single color model or, alternatively, a weighted subset of color models producing the best result for a particular task. The subsequent hurdle is how to obtain a proper fusion scheme for the algorithms so that the results are combined in an optimal setting. To achieve proper color model selection and fusion of feature detection algorithms, in this paper, we propose a method that exploits nonperfect correlation between color models or feature detection algorithms derived from the principles of diversification. As a consequence, a proper balance is obtained between repeatability and distinctiveness. The result is a weighting scheme which yields maximal feature discrimination. The method is verified experimentally for three different image feature detectors. The experimental results show that the fusion method provides feature detection results having a higher discriminative power than the standard weighting scheme. Further, it is experimentally shown that the color model selection scheme provides a proper balance between color invariance (repeatability) and discriminative power (distinctiveness)     

洁净都市主义 vs 非洁净设计：把水基础设施系统作为城市水景观

按照“洁净都市主义”的方式,建筑师、城市设计师、景观设计师通常假定那些关于水供给和处理的工程挑战需要通过一种技术性且最好看不见的方法来解决。这就让土地利用从流域的逻辑中分离了,并且导致了越来越多的洪水,干旱以及水污染。“非洁净设计”从另外一方面来说是指建筑师、城市设计师、景观设计师需要积极地参与现代水基础设施系统的设计中,并将其作为塑造城市形态以及迎合更广阔的人类、生态和美学目标的基础。这篇文章通过讲述两个分别来自于中国和欧洲的项目,来讨论如何将自然过程效能与空间设计策略相结合,整合工程、生态和城市设计思想。     

Advanced light microscopy core facilities: Balancing service,science and career

Core Facilities (CF) for advanced light microscopy (ALM) have become indispensable support units for research in the life sciences. Their organizational structure and technical characteristics are quite diverse, although the tasks they pursue and the services they offer are similar. Therefore, throughout Europe, scientists from ALM‐CFs are forming networks to promote interactions and discuss best practice models. Here, we present recommendations for ALM‐CF operations elaborated by the workgroups of the German network of ALM‐CFs, German Bio‐Imaging (GerBI). We address technical aspects of CF planning and instrument maintainance, give advice on the organization and management of an ALM‐CF, propose a scheme for the training of CF users, and provide an overview of current resources for image processing and analysis. Further, we elaborate on the new challenges and opportunities for professional development and careers created by CFs. While some information specifically refers to the German academic system, most of the content of this article is of general interest for CFs in the life sciences. Microsc. Res. Tech. 79:463–479, 2016. © 2016 THE AUTHORS MICROSCOPY RESEARCH AND TECHNIQUE PUBLISHED BY WILEY PERIODICALS, INC.     

Classifying color edges in video into shadow-geometry, highlight, or material transitions

We aim at using color information to classify the physical nature of edges in video. To achieve physics-based edge classification, we first propose a novel approach to color edge detection by automatic noise-adaptive thresholding derived from sensor noise analysis. Then, we present a taxonomy on color edge types. As a result, a parameter-free edge classifier is obtained labeling color transitions into one of the following types: 1) shadow-geometry, 2) highlight edges, and 3) material edges. The proposed method is empirically verified on images showing complex real world scenes.     

从灰到绿的基础设施——城市可持续设计与水资源综合管理

水基础设施是非常基本的,它可以解决很多重要的问题。现在,大多数的基础设施都是看不见的,人们一般只是使用这些设施,觉得从水龙头当中会流出无穷无尽的水。但是对于规划人员,景观设计师来说不是这样,从工程师的角度来说,这往往是灰色的角度。灰色概念从未来的角度来说,已经不太能适应城市未来的设计了,新的方式是绿色的,是非常好的。灰色的设计是在工业化时期,现代化开始的初期做的,