University of Cologne

About: University of Cologne is a education organization based out in Cologne, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 32050 authors who have published 66350 publications receiving 2210092 citations. The organization is also known as: Universität zu Köln & Universitatis Coloniensis.

A model of desynchronizing deep brain stimulation with a demand-controlled coordinated reset of neural subpopulations

Abstract: The coordinated reset of neural subpopulations is introduced as an effectively desynchronizing stimulation technique. For this, short sequences of high-frequency pulse trains are administered at different sites in a coordinated way. Desynchronization is easily maintained by performing a coordinated reset with demand-controlled timing or by periodically administering resetting high-frequency pulse trains of demand-controlled length. Unlike previously developed methods, this novel approach is robust against variations of model parameters and does not require time-consuming calibration. The novel technique is suggested to be used for demand-controlled deep brain stimulation in patients suffering from Parkinson's disease or essential tremor. It might even be applicable to diseases with intermittently emerging synchronized neural oscillations like epilepsy.

breathless, a Drosophila FGF receptor homolog, is essential for migration of tracheal and specific midline glial cells.

Abstract: A Drosophila homolog of the fibroblast growth factor (FGF) receptor was isolated and structurally characterized. After EMS mutagenesis or imprecise excisions of marked P elements inserted upstream to the gene, a phenotypic series of mutations in the locus was isolated. The mutants exhibit defects in the two embryonic tissues in which the receptor is expressed: the tracheal system and the midline. The tracheal cells fail to migrate in severe mutants and remain within the tracheal pits. Hypomorphic alleles exhibit partial migration of all tracheal branches; thus, the locus was termed breathless (btl). In the midline of the mutant embryos, the posterior pair of midline glial cells begins to migrate anteriorly, but fails to reach the posterior commissure. Abnormalities in cell migration appear to be a common denominator for the btl defects in these two disparate tissues. In hypomorphic mutants the cells exhibit partial migration but follow the normal tracts, suggesting that the presence of this receptor is essential for the ability of the migrating cells to recognize external guiding cues.

On the nucleus structure and activity of comet 67P/Churyumov-Gerasimenko

Abstract: Images from the OSIRIS scientific imaging system onboard Rosetta show that the nucleus of 67P/Churyumov-Gerasimenko consists of two lobes connected by a short neck. The nucleus has a bulk density less than half that of water. Activity at a distance from the Sun of >3 astronomical units is predominantly from the neck, where jets have been seen consistently. The nucleus rotates about the principal axis of momentum. The surface morphology suggests that the removal of larger volumes of material, possibly via explosive release of subsurface pressure or via creation of overhangs by sublimation, may be a major mass loss process. The shape raises the question of whether the two lobes represent a contact binary formed 4.5 billion years ago, or a single body where a gap has evolved via mass loss.