Visuelle Analyse medizinischer Daten

In der Medizin werden gro?e Mengen an Daten generiert, die sich auf diagnostische Prozeduren, Behandlungsentscheidungen und Ergebnisse der Behandlung beziehen. Medizinische Bilddaten, z. B. Computertomografie (CT) und Kernspintomografiedaten (MRT), werden h?ufig akquiriert. Diese Daten müssen effizient analysiert werden, um klinische Entscheidungen ad?quat zu unterstützen. Insbesondere müssen Bildanalysetechniken, wie die Segmentierung und Quantifizierung anatomischer Strukturen und die visuelle Exploration der Daten, integriert werden. Neben den Anforderungen der individuellen Behandlung ergeben sich weitere Herausforderungen für die Datenauswertung aus den Bedürfnissen der klinischen Forschung, der ?ffentlichen Gesundheitsvorsorge und der Epidemiologie. Die Rolle des Benutzers ist hier die eines Forschers, der Daten untersucht und dabei z. B. potenzielle Korrelationen zwischen Risikofaktoren und der Entstehung von Erkrankungen analysiert. Die visuelle Exploration, bei der oft mehrere koordinierte Ansichten genutzt werden, und statistische Analysen müssen dazu geeignet integriert werden. Oft sind dabei die r?umliche (geografische) Verteilung der Patienten und die zeitliche Entwicklung von Erkrankungsf?llen wesentlich. Daher müssen die medizinischen Daten in ihrem r?umlichen und zeitlichen Bezug repr?sentiert werden, sodass eine enge Verbindung zwischen geografischen Informationssystemen und der Datenvisualisierung entsteht.     

Pathways to a hydrogen fuel infrastructure in Norway

Hydrogen is expected to become an integral part of the Norwegian energy system in the future, primarily as transportation fuel. The NorWays project aims at providing decision support for introduction of hydrogen in the Norwegian energy system by modelling of energy system and hydrogen infrastructure at various spatial levels. GIS-based regional hydrogen demand scenarios and fuelling station networks have been generated, considering organic growth of regional hydrogen coverage and increasing density of hydrogen users over time. A regional model optimised supply scenarios for these fuelling station networks, including choice of production technology (biomass gasification, NG SMR, electrolysis, by-product hydrogen) and delivery (pipeline, truck, and onsite schemes), including integrated hydrogen delivery networks by truck and pipeline. The impact of energy price and GHG emission constraint scenarios on hydrogen production and delivery mix and average hydrogen costs is analysed, and conclusions on the effectiveness of policy measures are drawn.     

The PhytO3 Tech Crop Protection Technology – Trial Results in a 2,700 ha (6,500 acre) Soy Farm in Brazil

Extended field trial testing of the PhytO3 technology (applying sequentially and rapidly electrolyzed water, ozone in water, and UV-C radiation to control insects and replace chemical sprays) was conducted in Brazil on growing soy bean crops during December 2006 to March 2007. Despite the very poor growing conditions because of excessive rainfalls, the test crops all reached harvest and provided significant economic benefits to the farmer. Details of the testing program are described. In addition to eliminating the need for pesticides and insecticides, crops treated by the PhytO3 technology qualify as organic-grown crops, and therefore command about double prices on world markets.     

CDM baseline approaches and carbon leakage

Carbon leakage is an important issue because it can reduce the environmental effectiveness of international climate agreements. Under the Kyoto Protocol, the clean development mechanism (CDM) can potentially reduce carbon leakage significantly. To what extent this potential can be realized depends on how the CDM baseline approach accounts for this effect. We use a computable general equilibrium model to analyze the impact of three different baseline approaches, and find that they produce diverging results as the number of CDM projects increase. We do, however, find that under realistic assumptions on the level of CDM activity the CDM will significantly reduce carbon leakage irrespective of which baseline approach is used.     

Hot gas filter contributes to IGCC power plant's reliable operation

Steffen Heidenreich (Pall Schumacher GmbH) and Carlo Wolters (Nuon Power Buggenum BV) report and discuss the long-term operating performance of a ceramic hot gas filter unit installed in the Nuon Power IGCC coal gasification plant in Buggenum, The Netherlands.     

Precipitation of titanium nitride in low-alloyed steel during solidification

The microsegregation of titanium and manganese and the precipitation of titanium nitride during dendritic solidification were investigated on an Fe-0.051%Ti-0.77%Mn alloy. Carbon and nitrogen were introduced into the liquid sample via the gas phase. The material solidifies as delta ferrite at a carbon mass content of about 0.08% but predominantly as austenite at ≥ 0.3%. At ferritic solidification, an about 3fold enrichment of the titanium in the residual melt between secondary dendrite arms is attained by segregration, whereas in the corners between some dendrites or grains in maximum a 10fold enrichment was detected. TiN particles of 0.5 to 1.0 μm size are formed only in the regions of maximum segregation where the supersaturation is higher than 15fold. An equal supersaturation has been calculated for homogeneous nucleation in the melt. The number of particles is moderate at 0.016% nitrogen but low at 0.008%. At austenitic solidification, the titanium content in the residual melt increases to more than the 30fold of the starting value. Particles formed in the melt grow to diameters in the 2 μm range.     

Comparison of two quantitative proton density mapping methods in multiple sclerosis

Objective

Proton density (PD) mapping requires correction for the receive profile (RP), which is frequently performed via bias-field correction. An alternative RP-mapping method utilizes a comparison of uncorrected PD-maps and a value ρ(T1) directly derived from T1-maps via the Fatouros equation. This may be problematic in multiple sclerosis (MS), if respective parameters are only valid for healthy brain tissue. We aimed to investigate whether the alternative method yields correct PD values in MS patients.

Materials/methods

PD mapping was performed on 27 patients with relapsing-remitting MS and 27 healthy controls, utilizing both methods, yielding reference PD values (PD_ref, bias-field method) and PD_alt (alternative method).

Results

PD_alt-values closely matched PD_ref, both for patients and controls. In contrast, ρ(T1) differed by up to 3 % from PD_ref, and the voxel-wise correlation between PD_ref and ρ(T1) was reduced in a patient subgroup with a higher degree of disability. Still, discrepancies between ρ(T1) and PD_ref were almost identical across different tissue types, thus translating into a scaling factor, which cancelled out during normalization to 100 % in CSF, yielding a good agreement between PD_alt and PD_ref.

Conclusion

RP correction utilizing the auxiliary parameter ρ(T1) derived via the Fatouros equation provides accurate PD results in MS patients, in spite of discrepancies between ρ(T1) and actual PD values.

     

Quasi-Adiabatic Investigations of Lead in Indium

The use of melting or freezing temperatures of high-purity substances as thermometric fixed points requires a knowledge of the binary phase diagrams of these substances and remaining impurities at very small impurity concentrations. In this paper, a calorimetric apparatus for the measurement of the change in liquidus temperature of fixed-point metals due to dissolved impurities at quasi-adiabatic conditions is presented. This approach combines advantages of the fixed-point method and adiabatic calorimetry. It is more efficient for the screening of a range of impurity concentrations than a fixed-point cell, requires less constructional and experimental expenditure compared with an adiabatic calorimeter, but provides similar small uncertainties on the millikelvin level. Measurements were carried out to determine the influence of lead on the melting temperature of indium at mass fractions up to 6.93 %. The results are in very good agreement with previous measurements by means of slim fixed-point cells in the Physikalisch-Technische Bundesanstalt and confirm a minimum of the freezing point of \(-\) 178 mK at a mass fraction of about 3.7 %. It was demonstrated that this setup allows the investigation of binary phase diagrams with uncertainties less than 8 mK.