The tRNATyr multigene family of Triticum aestivum: genome organization, sequence analyses and maturation of intron-containing pre-tRNAs in wheat germ extract

AbstractSouthern analysis of Triticum DNA has revealed that nuclear tRNATyr genes are dispersed at a minimum of 16 loci in the genome. We have isolated six independent tRNATyr genes from a Triticum aestivum library in addition to three known members of the Triticum tRNATyr family. Four of the sequenced tRNATyr genes code for Triticum tRNA1Tyr and two code for tRNA2Tyr. Three genes encode tRNATyr which carry one or two nucleotide substitutions as compared to the conventional genes. The nine Triticum tRNATyr genes possess highly conserved intron sequences ranging in size from 12 to 14 nucleotides. A common secondary intron structure with the 5′ and 3′ splice site loops separated by five base pairs can be formed by all pre-tRNAsTyr which are efficiently spliced in the homologous wheat germ extract

Laserstrahlumformen von Profilen

Im Rahmen dieser Arbeit wurde ein werkzeugloses Verfahren zur Herstellung von Profilbiegeprototypen aufgebaut. Die Umformung erfolgt mittels laserinduzierter thermischer Spannungen, d.h. es werden keine äußeren mechanischen Kräfte eingebracht. -Da es sich um ein kinematisches Profilbiegeverfahren handelt, zeichnet sich diese Technologie besonders durch ihre Produktflexibilität aus. Zur Umsetzung des Vorhabens war es zunächst erforderlich, die prozeßtechnischen Grundlagen des Laserstrahlumformens von Profilen mit Hilfe der Finite-Element-Methode zu erarbeiten und die Ergebnisse so weit wie möglich experimentell zu verifizieren. Mit Hilfe des so gewonnenen Prozeßverständnisses war es möglich, ein analytisches Prozeßmodell zu entwickeln, mit dem die zu erwartenden Formänderungen und somit die Anzahl der erforderlichen Bestrahlungen abgeschätzt werden können. Die Biegewinkel für eine Einzelbestrahlung liegen typischerweise im Bereich von 0,1° bis 0,5°. Der Gesamtbiegewinkel und die Biegeradien können durch die Anzahl der Einzelbestrahlungen und deren Versatz in Profillängsrichtung festgelegt werden. Die verfahrensspezifischen Kenntnisse wurden in Form eines Technologieprozessors rechnergestützt archiviert und repräsentiert. Der Technologieprozessor analysiert die im CAD-Modell festgelegte Bauteilgeometrie und leitet selbständig unter Berücksichtigung von Werkstoff, Maschinen- und Verfahrensparametern die NC-Programme ab. Für die Bearbeitung wurde ein CO2-Laser mit einer Ausgangsleistung von 2,2 kW eingesetzt, als Führungsmaschine diente ein 5-Achs-Portalroboter, der um eine weitere rotatorische Achse für die Werkstückhandhabung erweitert wurde.The aim of this project was the development of a flexible rapid prototyping process for bending extrusions. The forming is carried out by means of laser induced thermal stresses, i.e. no external mechanical forces are necessary and therefore it is a kinematic bending process. To realize this aim, first of all basic process knowledge had to be investigated. Therefore the Finite Element Method was used and the results were verified experimentally as far as possible. The knowledge gained by this strategy was employed to build up an analytical process model. Herewith it is possible to estimate the resulting deformations and the number of irradiations necessary to achieve a desired curvature. The bend angle for a single irradiation is typically between 0.1° and 0.5°degrees. The total bend angle and the radii are determined by the number of irradiations and the gap between the irradiations in extrusions’ axis direction. The basic process knowledge is stored computer assisted in form of a technology processor. The technology processor analyses the workpiece shape in the CAD-model and generates automatically the NC-programs under consideration of material, machine- and process-parameters. For the machining a CO2 laser with 2.2 kW laser power was used, a 5-axes-gantry robot with an additional rotary axis was employed as guiding system

Soft Inkjet Circuits: Rapid Multi-Material Fabrication of Soft Circuits using a Commodity Inkjet Printer

Despite the increasing popularity of soft interactive devices, their fabrication remains complex and time consuming. We contribute a process for rapid do-it-yourself fabrication of soft circuits using a conventional desktop inkjet printer. It supports inkjet printing of circuits that are stretchable, ultrathin, high resolution, and integrated with a wide variety of materials used for prototyping. We introduce multi-ink functional printing on a desktop printer for realizing multi-material devices, including conductive and isolating inks. We further present DIY techniques to enhance compatibility between inks and substrates and the circuits' elasticity. This enables circuits on a wide set of materials including temporary tattoo paper, textiles, and thermoplastic. Four application cases demonstrate versatile uses for realizing stretchable devices, e-textiles, body-based and re-shapeable interfaces

Research of the structure of gallstones by IR-spectroscopy method

The composition of gallstones was studied by IR spectroscopy. It is shown that it is possible to establish the presence in the gallstones of such compounds as bilirubin and its salts, calcium phosphates, calcium carbonate, which are present in them in small amounts and difficult to determine

Computational design and optimization of electro-physiological sensors

Electro-physiological sensing devices are becoming increasingly common in diverse applications. However, designing such sensors in compact form factors and for high-quality signal acquisition is a challenging task even for experts, is typically done using heuristics, and requires extensive training. Our work proposes a computational approach for designing multi-modal electro-physiological sensors. By employing an optimization-based approach alongside an integrated predictive model for multiple modalities, compact sensors can be created which offer an optimal trade-off between high signal quality and small device size. The task is assisted by a graphical tool that allows to easily specify design preferences and to visually analyze the generated designs in real-time, enabling designer-in-the-loop optimization. Experimental results show high quantitative agreement between the prediction of the optimizer and experimentally collected physiological data. They demonstrate that generated designs can achieve an optimal balance between the size of the sensor and its signal acquisition capability, outperforming expert generated solutions

Zeno effect preventing Rabi transitions onto an unstable energy level

We consider a driven 2-level system with one level showing spontaneous decay to an otherwise uncoupled third level. Rabi transitions to the unstable level are strongly damped. This simple configuration can be used to demonstrate and to explore the quantum Zeno effect leading to a freezing of the system to the initial level. A comparison with repeated projection measurements is given. A treatment within a phenomenological theory of continuous measurements is sketched. The system visualizes the important role of null measurements (negative result measurements) and may serve as a good example for a truly continuous measurement.Comment: 13 pages, Latex, 2 EPS figure

A tunable narrowband entangled photon pair source for resonant single-photon single-atom interaction

We present a tunable, frequency-stabilized, narrow-bandwidth source of frequency-degenerate, entangled photon pairs. The source is based on spontaneous parametric downconversion (SPDC) in periodically-poled KTiOPO4 (PPKTP). Its wavelength can be stabilized to 850 or 854 nm, thus allowing to address two D-P transitions in 40Ca+ ions. Its output bandwidth of 22 MHz coincides with the absorption bandwidth of the calcium ions. Its spectral power density is 1.0 generated pairs/(s MHz mW).Comment: 3 pages, 3 figure