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Single Molecule Localization Microscopy Analyses of DNA-Repair Foci and Clusters Detected Along Particle Damage Tracks
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Laser beam microwelding of transparent plastics
No full textThe laser beam welding of transparent plastic components is still a challenge
according to the state of the art. A new approach for the joining of two transparent
polymeric components using ultrashort laser beam pulses is presented in
this report. In this respect, the high peak pulse intensity associated with these
lasers permits non-linear absorption processes and thus the production of a
locally well-defined heat source in the interior even of a transparent material or
at the boundary layer between two transparent substrates. Welding results for
transparent plastics of the cycloolefin copolymer and polycarbonate types are
shown in this study. In addition to the investigation into the influences of fundamental
process parameters on the weld geometry, the leak tightness is
demonstrated in this study using a microfluidic system
Hypersensitive H2 sensor based on polymer planar Bragg gratings coated with Pt-loaded WO3-SiO2
No full textThis letter demonstrates a novel hydrogen sensor based on a polymer planar Bragg grating coated with Pt-loaded WO3-SiO2. The reflected Bragg signal shows a distinct peak splitting correlated to substrate anisotropies originating from the injection molding process. Especially at low H2 concentrations, both sensing peaks
exhibit an outstanding response to the heat generated by the exothermic reaction between hydrogen molecules and coating. Thereby, a hydrogen volume ratio of 50 ppm
leads to a Bragg wavelength shift of -37 pm, which yields an outstandingly low detection limit of only 5 ppm H2 in air. Thus, functionalized polymer planar Bragg gratings are eminently suitable for H2 leak detection applications
High Dynamic Power Balancing for Dual Two-Level Inverters during High-Speed Machine Operation
No full textThis paper aims to present optimized square-wave modulation strategies for the dual two-level inverter, fed by two separate and galvanically isolated energy sources, to balance and control the energy distribution of both inverter systems. Especially for high-speed operation, the methods keep the machine in the required state while decreasing the switching operations to a minimum. Method one aims to compensate voltage fluctuations of variable DC-link voltages, while the second method ensures a symmetrical power distribution for the two inverter systems. In addition, both methods offer the possibility of adapting the amplitude of the usually fixed fundamental load voltage during square-wave modulation
Aufbau und Entwicklung von Gesundheitsnetzwerken im ländlichen Raum - Band 2 der Handbuchreihe zum Projekt „Gesundheitszentrum Spork: Aufbau und Verstetigung eines wirtschaftliche tragfähigen, interdisziplinären und zivilgesellschaftlichen Wertschöpfungsnetzwerkes im Quartier“
No full textDer zweite Band „Aufbau und Entwicklung von Gesundheitsnetzwerken im ländlichen Raum“ zeigt theoretisch und praxisnah wie ein regionales Themennetzwerk nachhaltig aufgebaut werden kann. Nach einer Einführung in die Grundlagen von Netzwerken, die aus unterschiedlichsten Akteuren – von professionellen Dienstleister*innen bis hin zu ehrenamtlich engagierten Personen – bestehen, werden wesentliche Gelingensfaktoren für
einen erfolgreichen Netzwerkaufbau aufgezeigt und Ansätze einer nachhaltigen Finanzierung im Sinne eines hybriden Geschäftsmodells vorgestellt. In Praxisbeispielen und Tipps wird immer wieder der Praxisbezug hergestellt. Die Vorstellung des Modellprojektes Gesundheitszentrum Spork komplettiert den Band, der Praktiker dazu ermuntern soll, eigene Netzwerkideen umzusetzen
Peak detection for MALDI mass spectrometry imaging data using sparse frame multipliers
No full textMALDI mass spectrometry imaging (MALDI MSI) is a spatially resolved analytical tool for biological tissue
analysis by measuring mass-to-charge ratios of ionized molecules. With increasing spatial and mass resolution of
MALDI MSI data, appropriate data analysis and interpretation is getting more and more challenging. A reliable
separation of important peaks from noise (aka peak detection) is a prerequisite for many subsequent processing
steps and should be as accurate as possible. We propose a novel peak detection algorithm based on sparse frame
multipliers, which can be applied to raw MALDI MSI data without prior preprocessing. The accuracy is evaluated
on a simulated data set in comparison with state-of-the-art algorithms. These results also show the proposed
method's robustness to baseline and noise effects. In addition, the method is evaluated on real MALDI-TOF data
sets, whereby spatial information can be included in the peak picking process.
Significance: The field of proteomics, in particular MALDI Imaging, encompasses huge amounts of data. The
processing and preprocessing of this data in order to segment or classify spatial structures of certain peptides or
isotope patterns can hence be cumbersome and includes several independent processing steps. In this work, we
propose a simple peak-picking algorithm to quickly analyze large raw MALDI Imaging data sets, which has a
better sensitivity than current state-of-the-art algorithms. Further, it is possible to get an overall overview of the
entire data set showing the most significant and spatially localized peptide structures and, hence, contributes all
data driven evaluation of MALDI Imaging data
Femtosecond laser inscription of waveguides and Bragg gratings in transparent cyclic olefin copolymers
No full textWe report on a femtosecond laser based fabrication technique that enables simultaneous single-step generation of optical waveguides and Bragg gratings inside bulk cyclic olefin copolymers. Due to the nonlinear absorption of focused and spatially modulated laser radiation with a wavelength of 514 nm and a pulse duration of 450 fs, a modification concluding a refractive index shift increase inside the substrate can be achieved. A sophisticated characterization of the generated waveguides by means of an elaborate cut-back method reveals a maximum attenuation of 3.2 dB/cm. Additionally, a Mach-Zehnder interferometer is used to examine the waveguide’s refractive index profile. The integrated Bragg grating structures exhibit reflectivities up to 95 % and a spectral full width at half maximum of 288 pm, at a Bragg wavelength of 1582 nm, whereas the grating period can be deliberately chosen by adapting the fabrication parameters. Thus, due to its increased flexibility and the resulting dispensability of cost-intensive phase masks, this method constitutes an especially promising fabrication process for polymer Bragg gratings inside of bulk materials