Humboldt University of Berlin

About: Humboldt University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Medicine. The organization has 33671 authors who have published 61781 publications receiving 1908102 citations. The organization is also known as: Humboldt-Universität zu Berlin & Universitas Humboldtiana Berolinensis.

Transforming BPEL to petri nets

Abstract: We present a Petri net semantics for the Business Process Execution Language for Web Services (BPEL) Our semantics covers the standard behaviour of BPEL as well as the exceptional behaviour (eg faults, events, compensation) The semantics is implemented as a parser that translates BPEL specifications into the input language of the Petri net model checking tool LoLA We demonstrate that the semantics is well suited for computer aided verification purposes

Bootstrapping the three-loop hexagon

Abstract: We consider the hexagonal Wilson loop dual to the six-point MHV amplitude in planar N = 4 super Yang-Mills theory We apply constraints from the operator product expansion in the near-collinear limit to the symbol of the remainder function at three loops Using these constraints, and assuming a natural ansatz for the symbol's entries, we determine the symbol up to just two undetermined constants In the multi-Regge limit, both constants drop out from the symbol, enabling us to make a non-trivial confirmation of the BFKL prediction for the leading-log approximation This result provides a strong consistency check of both our ansatz for the symbol and the duality between Wilson loops and MHV amplitudes Furthermore, we predict the form of the full three-loop remainder function in the multi-Regge limit, beyond the leading-log approximation, up to a few constants representing terms not detected by the symbol Our results confirm an all-loop prediction for the real part of the remainder function in multi-Regge 3 {yields} 3 scattering In the multi-Regge limit, our result for the remainder function can be expressed entirely in terms of classical polylogarithms For generic six-point kinematics other functions are required

Detecting actively translated open reading frames in ribosome profiling data

Abstract: RNA-sequencing protocols can quantify gene expression regulation from transcription to protein synthesis. Ribosome profiling (Ribo-seq) maps the positions of translating ribosomes over the entire transcriptome. We have developed RiboTaper (available at https://ohlerlab.mdc-berlin.de/software/), a rigorous statistical approach that identifies translated regions on the basis of the characteristic three-nucleotide periodicity of Ribo-seq data. We used RiboTaper with deep Ribo-seq data from HEK293 cells to derive an extensive map of translation that covered open reading frame (ORF) annotations for more than 11,000 protein-coding genes. We also found distinct ribosomal signatures for several hundred upstream ORFs and ORFs in annotated noncoding genes (ncORFs). Mass spectrometry data confirmed that RiboTaper achieved excellent coverage of the cellular proteome. Although dozens of novel peptide products were validated in this manner, few of the currently annotated long noncoding RNAs appeared to encode stable polypeptides. RiboTaper is a powerful method for comprehensive de novo identification of actively used ORFs from Ribo-seq data.

Playing Super Mario induces structural brain plasticity: Gray matter changes resulting from training with a commercial video game.

Abstract: Video gaming is a highly pervasive activity, providing a multitude of complex cognitive and motor demands. Gaming can be seen as an intense training of several skills. Associated cerebral structural plasticity induced has not been investigated so far. Comparing a control with a video gaming training group that was trained for 2 months for at least 30 min per day with a platformer game, we found significant gray matter (GM) increase in right hippocampal formation (HC), right dorsolateral prefrontal cortex (DLPFC) and bilateral cerebellum in the training group. The HC increase correlated with changes from egocentric to allocentric navigation strategy. GM increases in HC and DLPFC correlated with participants' desire for video gaming, evidence suggesting a predictive role of desire in volume change. Video game training augments GM in brain areas crucial for spatial navigation, strategic planning, working memory and motor performance going along with evidence for behavioral changes of navigation strategy. The presented video game training could therefore be used to counteract known risk factors for mental disease such as smaller hippocampus and prefrontal cortex volume in, for example, post-traumatic stress disorder, schizophrenia and neurodegenerative disease.