Chromosome painting: a useful art

Chromosome 'painting' refers to the hybridization of fluorescently labeled chromosome-specific, composite probe pools to cytological preparations. Chromosome painting allows the visualization of individual chromosomes in metaphase or interphase cells and the identification of both numerical and structural chromosomal aberrations in human pathology with high sensitivity and specificity. In addition to human chromosome-specific probe pools, painting probes have become available for an increasing range of different species. They can be applied to cross-species comparisons as well as to the study of chromosomal rearrangements in animal models of human diseases. The simultaneous hybridization of multiple chromosome painting probes, each tagged with a specific fluorochrome or fluorochrome combination, has resulted in the differential color display of human (and mouse) chromosomes, i.e. color karyotyping. In this review, we will summarize recent developments of multicolor chromosome painting, describe applications in basic chromosome research and cytogenetic diagnostics, and discuss limitations and future directions.     

Charakterisierung des quasilinearen Raumes I(R) und Klassifizierung der quasilinearen Räume der Dimension 1 und 2

In this paper we investigate the quasilinear spacesQ with dimQ≤2 and characterize the special role of the quasilinear space I(R), the space of all compact intervals overR.     

The determination of diffusion coefficients in activated carbons made from bituminous coal

The gas chromatographic method has been used to measure the effective diffusion coefficients D_e or the diffusion parameters $\text{D}{}_{\mathrm{e}}\text{d}{}^2$. Nitrogen was used as a carrier gas, krypton-85 as test gas. The tests were carried out on different activated carbons made from air-preoxidized bituminous coals whose pore structure as a function of the burn-off was known. The diffusion parameters for krypton were found to increase exponentially with the mean micropore diameter of the activated carbons which was varied in our tests between 5.8 and 7.0 Å. For activated carbon with the narrowest pores the activation energy of krypton diffusion was found to be 2.8 kcal/mol. In case of such a product the diffusion time is not rigidly dependent on the particle diameter as would have to be expected theoretically. With increasing micropore diameter this dependency is attenuated very rapidly, and in carbons with a mean micropore diameter above ca. 6.8 Å it exists no longer at all. To check the results, gravimetric studies on the adsorption kinetics of krypton in vacua and on the desorption kinetics using the gas flushing method were made. It was found that the results obtained by the gas chromatographic method and the gas flushing method were in good agreement, whereas the diffusion parameters obtained by measurements in vacuo were by one order of magnitude lower. The findings are discussed in relation to the pore structure of the adsorbent and the properties of the sorbate. The limits of the different measuring methods are shown.     

The yield,fatty acid composition and physical properties of milk fat obtained by feeding soya oil to dairy cows

The presence in the bovine mammary gland of a desaturase specific for the conversion of stearic to oleic acid allows the manipulation of the physical properties of milk fat by varying the dietary intake of C₁₆ and C₁₈ fatty acids. In particular, feeding the dairy cow an oil with a high C₁₈: C₁₆ ratio should allow the proportion of milk fat that is liquid at 5°C to be increased, with a consequent improvement in the low-temperature spreadability of butter. In this paper, the effect of feeding concentrate rations containing (a) soya oil as the free oil and as cracked soya beans; (b) various levels of soya oil, the ration being offered twice or 24-times daily, on the thermal properties of the milk fat and on the yield of milk constituents is examined in detail. Feeding ratios containing free soya oil greatly increased the proportion of milk fat liquid at 5°C, whereas cracked soya oil gave only slight increases. Proportion and yield of milk fat were decreased by feeding soya oil twice daily but were increased by continuous feeding.     

Large-Scale CFD Data Handling in a VR-Based Otorhinolaryngological CAS-System using a Linux-Cluster

Many of the operations to eliminate complaints concerning respiration impairments fail. In order to improve the success rate, it is important to recognize the responsiveness of the flow field within the nasal cavities. Therefore, we are developing a computer assisted surgery (CAS) system that combines computational fluid dynamics (CFD) and virtual reality (VR) technology. However, the primary prerequisite for VR-based applications is real-time interaction. A single graphics workstation is not capable of satisfying this condition and of simultaneously calculating flow features employing the huge CFD data set. In this paper, we will present our approach of a distributed system that relieves the load on the graphics workstation and makes use of an off-the-shelf parallel Linux cluster calculating streamlines. Moreover, we introduce first results and discuss remaining difficulties.     

Upscaling and automation of electrophysiology: toward high throughput screening in ion channel drug discovery

Effective screening of large compound libraries in ion channel drug discovery requires the development of new electrophysiological techniques with substantially increased throughputs compared to the conventional patch clamp technique. Sophion Bioscience is aiming to meet this challenge by developing two lines of automated patch clamp products, a traditional pipette-based system called Apatchi-1, and a silicon chip-based system QPatch. The degree of automation spans from semi-automation (Apatchi-1) where a trained technician interacts with the system in a limited way, to a complete automation (QPatch 96) where the system works continuously and unattended until screening of a full compound library is completed. The performance of the systems range from medium to high throughputs.     

Integrated planning of acquisition,disassembly and bulk recycling: a case study on electronic scrap recovery

Abstract. Due to national and supranational legislation activities, the recovery of discarded products will attain an increasing momentum. Electronic equipment consists of many different parts and materials. Therefore, the related recovery process is often divided into disassembly to remove harmful substances or reusable parts and into bulk recycling to recover ferrous and non-ferrous metals. In order to consider the interactions between choice of scrap to be recovered (acquisition problem), disassembly and bulk recycling, a mixed-integer linear programming model for integrated planning of these stages is presented in this case study. It is applied to determine the daily allocation of products to processes for a major electronic scrap recovery centre that faces limited processing capacities and market restrictions. The optimization calculations covering typical discarded electronic products to be recycled in the related centre lead to a relevant improvement of the economic success. RID="*" ID="*" The authors would like to thank the German “Bundesministerium für Bildung und Forschung” (Federal Ministry of Education and Research) for supporting the research project “Substance Flow Oriented Closed Loop Supply Chain Management in the Electrical and Electronic Equipment Industry (STREAM)rdquo;. Correspondence to: T. Spengler     

Origin of an absorption band peaked at 5560 cm−1 and related to divacancies in Si1−x Gex

It is found that two types of centers are formed in Si_1?x Ge_x single crystals as a result of irradiation with fast electrons: divacancies (V ₂) characteristic of silicon and the V ₂ ^* centers; the latter are complexes of divacancies V ₂ with germanium atoms (V ₂Ge). It is shown that an absorption band peaked at about 5560 cm^?1 is a superposition of two absorption bands that correspond to the above centers. The V ₂ divacancies diffuse during isochronous heat treatment and interact with germanium atoms, thus giving rise to additional V ₂ ^* centers. The latter have a higher thermal stability than the V ₂ centers do, and their annealing temperature increases with increasing content of germanium.