Extracting the Beat: An Experience-dependent Complex Integration of Multisensory Information Involving Multiple Levels of the Nervous System

In a series of studies we have shown that movement (or vestibular stimulation) that is synchronized to every second or every third beat of a metrically ambiguous rhythm pattern biases people to perceive the meter as a march or as a waltz, respectively. Riggle (this volume) claims that we postulate an "innate", "specialized brain unit" for beat perception that is "directly" influenced by vestibular input. In fact, to the contrary, we argue that experience likely plays a large role in the development of rhythmic auditory-movement interactions, and that rhythmic processing in the brain is widely distributed and includes subcortical and cortical areas involved in sound processing and movement. Further, we argue that vestibular and auditory information are integrated at various subcortical and cortical levels along with input from other sensory modalities, and it is not clear which levels are most important for rhythm processing or, indeed, what a "direct" influence of vestibular input would mean. Finally, we argue that vestibular input to sound location mechanisms may be involved, but likely cannot explain the influence of vestibular input on the perception of auditory rhythm. This remains an empirical question for future research

New inner drum test bench for dynamic tests of PLT and truck tires

At the Institute of Vehicle System Technology at the Karlsruhe Insti-tute of Technology (KIT) a new inner drum test bench had been build up and put into operation in 2022. This test bench allows the analysis of PLT (passenger and light truck) and truck tires under realistic quasi-stationary and dynamic loads on different real track surfaces. The test bench consists of a rotating drum and a load unit based on a servo-hydraulic hexapod unit, which allows almost any setting of the operating conditions of the tire with frequencies of up to 30 Hz. An electric wheel drive unit allows the tire to be loaded with respective drive and braking torques. In addition, the test bench construction principle allows the investigation of chassis systems, which can be attached to the Hexapod and be operated as a quarter vehicle. Initially, the authors discuss the future demands on the experimental analysis of tires and identify major research fields for the usage of the new test bench. After this introduction, the authors present and describe details of the construc-tion and the main technical specifications of the new test bench. The technical specifications will be compared to requirements resulting from the operation of PLT and truck tires, so that the operation field of the new test bench is more precisely described. Finally, first experimental results will be presented, that demonstrate the functionality of the test bench and give a first impression of fu-ture applications of the test bench

Ebbie: automated analysis and storage of small RNA cloning data using a dynamic web server

BACKGROUND: DNA sequencing is used ubiquitously: from deciphering genomes[1] to determining the primary sequence of small RNAs (smRNAs) [2-5]. The cloning of smRNAs is currently the most conventional method to determine the actual sequence of these important regulators of gene expression. Typical smRNA cloning projects involve the sequencing of hundreds to thousands of smRNA clones that are delimited at their 5' and 3' ends by fixed sequence regions. These primers result from the biochemical protocol used to isolate and convert the smRNA into clonable PCR products. Recently we completed a smRNA cloning project involving tobacco plants, where analysis was required for ~700 smRNA sequences[6]. Finding no easily accessible research tool to enter and analyze smRNA sequences we developed Ebbie to assist us with our study. RESULTS: Ebbie is a semi-automated smRNA cloning data processing algorithm, which initially searches for any substring within a DNA sequencing text file, which is flanked by two constant strings. The substring, also termed smRNA or insert, is stored in a MySQL and BlastN database. These inserts are then compared using BlastN to locally installed databases allowing the rapid comparison of the insert to both the growing smRNA database and to other static sequence databases. Our laboratory used Ebbie to analyze scores of DNA sequencing data originating from an smRNA cloning project[6]. Through its built-in instant analysis of all inserts using BlastN, we were able to quickly identify 33 groups of smRNAs from ~700 database entries. This clustering allowed the easy identification of novel and highly expressed clusters of smRNAs. Ebbie is available under GNU GPL and currently implemented on CONCLUSION: Ebbie was designed for medium sized smRNA cloning projects with about 1,000 database entries [6-8].Ebbie can be used for any type of sequence analysis where two constant primer regions flank a sequence of interest. The reliable storage of inserts, and their annotation in a MySQL database, BlastN[9] comparison of new inserts to dynamic and static databases make it a powerful new tool in any laboratory using DNA sequencing. Ebbie also prevents manual mistakes during the excision process and speeds up annotation and data-entry. Once the server is installed locally, its access can be restricted to protect sensitive new DNA sequencing data. Ebbie was primarily designed for smRNA cloning projects, but can be applied to a variety of RNA and DNA cloning projects[2,3,10,11]

Three-transition cascade erbium laser at 1.7, 2.7, and 1.6 µm

We report on an upconversion cascade laser in an erbium-doped ZBLAN fiber emitting simultaneously on the three transitions 4S3/2 -> 4I9/2 at 1.7 um, 4I11/2 -> 4I13/2 at 2.7 um, and 4I13/2 -> 4I15/2 at 1.6 um. At moderate pump powers, the laser transition at 1.6 um supports 2.7-um lasing and permits a slope efficiency at 2.7 um of 15% versus launched pump power. Above the threshold of upconversion lasing at 1.7 um, the slope efficiency at 2.7 um increases to 25.4%. Taking pump excited-state absorption into account, this value represents more than 90% of the theoretical slope efficiency. A transversely single-mode output power of 99 mW is achieved at 2.7 um

Double cascade erbium fiber laser at 1.7 µm, 2.7 µm, and 1.6 µm

The output power of the erbium laser at 2.7 um (4I11/2 -> 4I13/2) is enhanced due to simultaneous laser action at 1.7 um (4S3/2 -> 4I9/2) and 1.6 um (4I13/2 -> 4I15/2) in an Er3+-doped fluorozirconate fiber. The laser cascade overwhelms the saturation effect for the transition at 2.7 um by suppressing the laser transition at 850 nm (4S3/2 -> 4I13/2) with lasing at 1.7 um [1]. The population of the level 4S3/2 occurs for pump wavelengths around 800 nm due to strong pump excited state absorption (ESA). A fluorozirconate fiber (core diameter: 6 um, N.A.: 0.4, 3000 ppm Er3+, length: 1.1 m) fabricated be Le Verre Fluoré was used for the measurements. The fiber laser set-up was of the Fabry-Perot type. The mirrors used as input and output mirror had reflectivities of 99% at 1.7 um, 98% at 1.6 um, 32% at 2.7 um and approximately 10% at 850 nm. Transmissivity at 792 nm was 84%. It was estimated that 70% of the impinging pump power was launched into the core. Using the pump wavelength at 792 nm, the laser at 2.7 um was the first initiated. The transition at 1.7 um had a higher threshold power at about 300 mW launched pump power. Figure 1 shows the laser spectra for the cascade lasers at 1.6 um and 1.7 um. The maxima are located at 1.6 um and 1.72 um. [1] M. Pollnau, Ch. Ghisler, G. Bunea, M. Bunea, W. Lüthy, H. P. Weber: Appl. Phts. Lett. 66, No. 26, (June 1995), p. 3564-3566. [2] J. Schneider, D. Hauschild, Ch. Frerichs, L. Wetenkamp: Int. J. Infrared and Millimeter Waves 15, No. 11, (November 1994), p. 1907-1922

Ribonucleoprotein Purification and Characterization Using RNA Mango

The characterization of RNA–protein complexes (RNPs) is a difficult but increasingly important problem in modern biology. By combining the compact RNA Mango aptamer with a fluorogenic thiazole orange desthiobiotin (TO1-Dtb or TO3-Dtb) ligand, we have created an RNA tagging system that simplifies the purification and subsequent characterization of endogenous RNPs. Mango-tagged RNP complexes can be immobilized on a streptavidin solid support and recovered in their native state by the addition of free biotin. Furthermore, Mango-based RNP purification can be adapted to different scales of RNP isolation ranging from pull-down assays to the isolation of large amounts of biochemically defined cellular RNPs. We have incorporated the Mango aptamer into the S. cerevisiae U1 small nuclear RNA (snRNA), shown that the Mango-snRNA is functional in cells, and used the aptamer to pull down a U1 snRNA-associated protein. To demonstrate large-scale isolation of RNPs, we purified and characterized bacterial RNA polymerase holoenzyme (HE) in complex with a Mango-containing 6S RNA. We were able to use the combination of a red-shifted TO3-Dtb ligand and eGFP-tagged HE to follow the binding and release of the 6S RNA by two-color native gel analysis as well as by single-molecule fluorescence cross-correlation spectroscopy. Together these experiments demonstrate how the Mango aptamer in conjunction with simple derivatives of its flurophore ligands enables the purification and characterization of endogenous cellular RNPs in vitro