Colour-Specific Microfluidic Droplet Detection for Molecular Communication

Droplet-based microfluidic systems are a promising platform forlab-on-a-chip (LoC) applications. These systems can also be used toenhance LoC applications with integrated droplet control information or for data transmission scenarios in the context of molecular communication. For both use-cases the detection and characterisation of droplets in small microfluidic channels is crucial. So far, only complex lab setups with restricted capabilities have been presented as detection devices. We present a new low-cost and portable droplet detector. The device is used to confidently distinguish between individual droplets in a droplet-based microfluidic system. Using on-off keying a 16-bit sequence is successfully transmittedfor the first time with such a setup. Furthermore, the devices capabilities to characterise droplets regarding colour and size are demonstrated. Such an application of a spectral sensor in a microfluidic system presents new possibilities, such as colour-coded data transmission or analysis of droplet content

Structure of a Sixteen Heme Cytochrome by X-Ray Crystallography.

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Accuracy in Laue X-ray diffraction analysis of protein structures

The accuracy in protein structure analysis based on Laue X-ray diffraction has been investigated for the example of two orthorhombic structures of bovine pancreatic trypsin (BPT). The precision in the Laue structure factors and the contrast in electron-density maps were used as criteria. A comparison with the results of previous analyses based on conventional crystal rotation methods showed that high resolution around 1.4 Å may be reached with both monochromatic and polychromatic techniques. Electron-density maps exhibited significantly lower contrast when calculated on the basis of Laue structure amplitudes, due to inefficient exploration of reciprocal space at low resolution by the Laue method even in the case of a broad bandwidth and inclusion of exposures from several different crystal orientations. Laue data were recorded on photographic film and processed using the program LAUEMAD [Bartunik & Borchert (1989). Acta Cryst. A45, 718-726]. The empirically derived wavelength scaling factors based on a comparison of equivalent reflection intensities were in good agreement with theoretical estimates over a broad wavelength range. One BPT structure was refined on the basis of Laue structure amplitudes (current R-factor 24% at 1.8 Å resolution)

Проблемы технической оснащённости России для работы в условиях Арктики

Cytochrome c oxidase is a respiratory enzyme catalysing the energy-conserving reduction of molecular oxygen to water. The crystal structure of the ba(3)-cytochrome c oxidase from Thermus thermophilus has been determined to 2.4 Å resolution using multiple anomalous dispersion (MAD) phasing and led to the discovery of a novel subunit IIa. A structure-based sequence alignment of this phylogenetically very distant oxidase with the other structurally known cytochrome oxidases leads to the identification of sequence motifs and residues that seem to be indispensable for the function of the haem copper oxidases, e.g. a new electron transfer pathway leading directly from Cu(A) to Cu(B). Specific features of the ba(3)-oxidase include an extended oxygen input channel, which leads directly to the active site, the presence of only one oxygen atom (O(2–), OH(–) or H(2)O) as bridging ligand at the active site and the mainly hydrophobic character of the interactions that stabilize the electron transfer complex between this oxidase and its substrate cytochrome c. New aspects of the proton pumping mechanism could be identified

Предельные метрологические характеристики генераторов сигналов на основе прямого цифрового синтеза

Выпускная квалификационная работа 75 страниц, 24 рисунка, 26 таблиц, 16 источников, 4 приложения. Ключевые слова: генератор сигналов, метрологические характеристики, амплитуда, период, коэффициент гармоник. Объектами исследования являются характеристики гармонических колебаний: амплитуда, период и коэффициент гармоник. Цель работы – исследование метрологических характеристик генераторов сигналов на основе прямого цифрового синтеза. В ходе работы проводилось определение нестабильности амплитуды, нестабильности периода и коэффициента гармоник путем моделирования с помощью программного обеспечения для инженерных вычислений – Mathcad. В результате работы были получены зависимости, позволяющие оценить необходимый период дискретизации по заданной нестабильности амплитуды, нестабильности периодаFinal qualifying work is 75 pages, 24 figures, 26 tables, 16 sources, 4 of the annex. Keywords: signal generator, the metrological characteristics, amplitude, period, total harmonic distortion. The objects of study are the characteristics of harmonic vibrations: amplitude, period, and total harmonic distortion. The purpose is research of metrological characteristics signal generator based on direct digital synthesis. The work was carried out determining the amplitude of instability, instability period and harmonic distortion by simulation software for engineering calculations - Mathcad. As a result of the work were obtained according to assess the required sampling period for a given amplitude instability, instability period and harmonic distortion