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Remagen, Germany

Based on a roller kiln plant, options are presented to reduce energy costs by the optimization of the exergy efficiency. To achieve this in a first step the energetic link of kiln and dryer is undocked and in this way the possibility is generated to supply dryers independently from kiln energy. This enables an optimized energy supply of the dryers by utilization of cogeneration. Besides this electric energy supply can be achieved by ORC units or thermoelectric generators. Source

Wittkowski K.M.,Rockefeller University | Sonakya V.,Rockefeller University | Bigio B.,Rockefeller University | Tonn M.K.,Hochschule Koblenz | And 4 more authors.
Translational Psychiatry | Year: 2014

The prevalence of autism spectrum disorders (ASDs) has increased 20-fold over the past 50 years to >1% of US children. Although twin studies attest to a high degree of heritability, the genetic risk factors are still poorly understood. We analyzed data from two independent populations using u-statistics for genetically structured wide-locus data and added data from unrelated controls to explore epistasis. To account for systematic, but disease-unrelated differences in (non-randomized) genome-wide association studies (GWAS), a correlation between P-values and minor allele frequency with low granularity data and for conducting multiple tests in overlapping genetic regions, we present a novel study-specific criterion for 'genome-wide significance'. From recent results in a comorbid disease, childhood absence epilepsy, we had hypothesized that axonal guidance and calcium signaling are involved in autism as well. Enrichment of the results in both studies with related genes confirms this hypothesis. Additional ASD-specific variations identified in this study suggest protracted growth factor signaling as causing more severe forms of ASD. Another cluster of related genes suggests chloride and potassium ion channels as additional ASD-specific drug targets. The involvement of growth factors suggests the time of accelerated neuronal growth and pruning at 9-24 months of age as the period during which treatment with ion channel modulators would be most effective in preventing progression to more severe forms of autism. By extension, the same computational biostatistics approach could yield profound insights into the etiology of many common diseases from the genetic data collected over the last decade. © 2014 Macmillan Publishers Limited. Source

Krause O.,Hochschule Koblenz | Klein T.,Hochschule Koblenz | Tischer D.,Hochschule Koblenz | Schwarz K.,Hochschule Koblenz | And 2 more authors.
InterCeram: International Ceramic Review | Year: 2014

This paper reports on the results of a science project conducted during the last two years. In this project a focus was set on the rheological and setting properties as a function of the mixing energy applied in dry and wet state. A proper adjustment of mixing time and velocity even prior to the water addition is a powerful measure to enhance the compaction properties of concretes. The products are more homogenous and show improved properties with special regard to their rheology, density, open porosity and mechanical strength. On the other hand, these encouraging results depict that results in development and research work should be read in a more qualitative way unless the preparation routine of test specimen are clearly communicated. It has to be proposed, that the mixing procedure should be an indispensable part of the procedure description. Future developments of refractory castables will even focus more consequently on the design of the particle distribution of the micro fine components in order to produce products with enhanced durability in service. However, if the matrix design turns more complex the requirements for a perfect homogenization increase exceptionally. It is necessary to define the optimum mixing energy for a proper deagglomeration without an unwanted warming of the mix that will lead to shorter pot times. As reported by many authors the setting velocity of plain cement-water suspensions is not predictable in a wanted correctness. As a spinoff of the said project, it can be shown, that the starting time of the crystallization of cement hydrate phases that correlates with the setting of the water cement suspensions is strongly dependent on the mixing energy. The starting time of the temperature increases and the distinct slope of the temperature evolution is a function of the deagglomeration degree of the cement particles during mixing. Source

Rausch M.,Hochschule Koblenz | Schyboll F.,Hochschule Koblenz | Neeb H.,Hochschule Koblenz
Technisches Messen | Year: 2013

There is an increasing tendency towards the use of combined MR/PET scanners and combined MR-Linac (Linear accelerator) systems in both clinical and research settings. The current work therefore investigated the effects of ionising radiation on the acquired MR signal, both experimentally and using a simple theoretical model. We have observed a phase signal change in the radiated area inside a water phantom. However, the theoretical basis of this observation is not fully covered by the employed model and needs further research. © 2013 by Walter de Gruyter Berlin Boston 2013. Source

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