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C60 Fullerene Effects on Diphenyl-N-(trichloroacetyl)-amidophosphate Interaction with DNA In Silico and Its Cytotoxic Activity Against Human Leukemic Cell Line In Vitro
No full textNew representative of carbacylamidophosphates - diphenyl-N-(trichloroacetyl)-amidophosphate (HL), which contains two phenoxy substituents near the phosphoryl group, was synthesized, identified by elemental analysis and IR and NMR spectroscopy, and tested as a cytotoxic agent itself and in combination with C60 fullerene.
According to molecular simulation results, C60 fullerene and HL could interact with DNA and form a rigid complex stabilized by stacking interactions of HL phenyl groups with C60 fullerene and DNA G nucleotide, as well as by interactions of HL CCl3 group by ion-π bonds with C60 molecule and by electrostatic bonds with DNA G nucleotide.
With the use of MTT test, the cytotoxic activity of HL against human leukemic CCRF-CM cells with IC50 value detected at 10 μM concentration at 72 h of cells treatment was shown. Under combined action of 16 μM C60 fullerene and HL, the value of IC50 was detected at lower 5 μM HL concentration and at earlier 48 h period of incubation, besides the cytotoxic effect of HL was observed at a low 2.5 μM concentration at which HL by itself had no influence on cell viability. Binding of C60 fullerene and HL with minor DNA groove with formation of a stable complex is assumed to be one of the possible reasons of their synergistic inhibition of CCRF-CЕM cells proliferation.
Application of C60 fullerene in combination with 2.5 μM HL was shown to have no harmful effect on structural stability of blood erythrocytes membrane. Thus, combined action of C60 fullerene and HL in a low concentration potentiated HL cytotoxic effect against human leukemic cells and was not followed by hemolytic effect
Atmospheric pressure plasma-assisted femtosecond laser engraving of aluminium
Get PDFIn this contribution, we report on the impact of direct dielectric barrier discharge argon plasma at atmospheric pressure on femtosecond laser engraving of aluminium. It is shown that the assisting plasma strongly affects the surface geometry and formation of spikes of both laser-engraved single lines and patterns of adjacent lines with an appropriate overlap. Further, it was observed that the overall ablation depth is significantly increased in case of large-scale patterning whereas no notable differences in ablation depth are found for single lines. Several possible mechanisms and underlying effects of this behaviour are suggested. The increase in ablation depth is supposed to be due to a plasma-induced removal of debris particles from the cutting point via charging and oxidation as supported by EDX analysis of the re-solidified debris. Furthermore, the impact of a higher degree of surface wrinkling as well as direct interactions of plasma species with the aluminium surface on the ablation process are discussed
A Simple Way to Compute the Number of Vehicles That Are Required to Operate a Periodic Timetable
No full textWe consider the following planning problem in public transportation: Given a periodic timetable, how many vehicles are required to operate it? In [Julius Paetzold et al., 2017], for this sequential approach, it is proposed to first expand the periodic timetable over time, and then answer the above question by solving a flow-based aperiodic optimization problem. In this contribution we propose to keep the compact periodic representation of the timetable and simply solve a particular perfect matching problem. For practical networks, it is very much likely that the matching problem decomposes into several connected components. Our key observation is that there is no need to change any turnaround decision for the vehicles of a line during the day, as long as the timetable stays exactly the same
The Directive on Antitrust Damages Actions and the European Leniency Program
Get PDFDie Europäische Kronzeugenregelung ist eines der wichtigsten Instrumente des Europäischen Wettbewerbsrechts. Kartellmitgliedern werden Anreize geboten, damit sie illegale, für den Wettbewerb schädliche, geheime Absprachen gegenüber der Europäischen Kommission offenlegen. Ausschlaggebend für die Teilnahme am Kronzeugenprogramm ist für Kartelle unter anderem, ob ein in Aussicht stehender vollständiger oder teilweiser Erlass der Geldbuße das Risiko von zivilrechtlichen Schadensersatzansprüchen überwiegt. Seitens der Europäischen Kommission müssen Anreize zur Teilnahme am Kronzeugenprogramm, aber auch eine wirksame Rechtsdurchsetzung für Geschädigte implementiert werden. Mit der Kartellschadensersatzrichtlinie soll eine harmonisierte, effektive Durchsetzung von Schadensersatzansprüchen gewährleistet werden. Dieser Beitrag kommt zu dem Schluss, dass die Stärkung der Durchsetzung zivilrechtlicher Ansprüche nicht konsequent umgesetzt werden konnte, da eine gewisse Diskrepanz zwischen dem Schutzzweck der Richtlinie und der Erhaltung des Europäischen Kronzeugenprogramms besteht.The European Leniency Program constitutes an important part of the anti-cartel enforcement and thus of the protection of sound competition. By offering incentives to cartel members, illegal detrimental agreements can be detected and penalized in order to stop infringement of the internal market. Companies willing to participate in the European Leniency Program however have to evaluate whether the offered incentives, i.e. full or partial immunity from fines, outweighs the possible risk resulting from private enforcement. With the Directive on Antitrust Damages Actions, the harmonized, effective enforcement of antitrust damage claims shall be ensured. The possibility of private enforcement constitutes a major threat to leniency applicants. It is the European Commissions’ task and challenge to design an anti-cartel enforcement providing sufficient incentives for whistleblowers, while concurrently strengthening individuals suffering from cartels. The results show the dilemma and contradiction between the protection of the individual by strengthening the private enforcement and the need for an appealing leniency program
Development of a Smartphone Based Reader for the Quantitative Analysis of Lateral Flow Assays
No full textSmartphones are developing into all-purposes devices. In the present work, the employment/application of smartphones as medical devices in home care and point-of-care (POC) diagnostics are investigated in the analysis of Lateral Flow Assays (LFA). A smartphone-based LFA reader was developed for the quantitative analysis of D-Dimer – a biomarker indicating e.g. thrombotic event or danger of embolism.The proof-of-concept has been shown with multiple smartphones in establishing: (I) Optimal dimensions of the LFA cell of 72.11mm distance of smartphone to D-Dimer test leading to a coefficients of variances (CV) between 0.8% and 4.2%. (II) Inter-device investigations: CVs around 13.5%; a limit of detection (LOD) of 100ng/ml (DDU) D-Dimer. (III) Inter-smartphone investigations: CV about 16%, a limit of detection (LOD) at 66.4ng/ml (DDU). (IV) Calibrations: CV and LOD of three smartphones are comparable to the commercial available LFA reader. Further development to put the multiple smartphone-based LFA reader on the market
Online Glucose Measurement in DMEM for In Vitro Cell Culture
No full textIn-vitro cell culture offers the ability to grow individual cells and monitor their behaviour in a controlled environment over a certain time. During culture, different parameters have to be controlled to ensure a vital growth of cells. The most important parameters are temperature, pH-value, oxygen and carbon dioxide levels as well as the glucose concentration. All of these parameters influence the growth ability of the cell culture and should be monitored online. The online monitoring of glucose was achieved with a novel GOD based sensor which enabled a real-time measurement of glucose during cell culture. A first-time characterisation of the sensor was carried out in the culture medium DMEM. In addition, material properties of the culture system were investigated. At first to establish a baseline measurement, the sensor was placed in different glucose concentrations dissolved in Water-KCl mixture at 25 °C inside a batch chamber under constant stirring. Afterwards, the temperature was increased to 37 °C to simulate a cell culture environment. In addition, the system was transferred into a flow-through reaction chamber. The highest response signal and the most stable signal was achieved at 37 °C with DMEM during flow-through measurement. Based on these measurements online glucose monitoring in cell culture was possible to determine the glucose consumption for each cell which is important for future human-on-a-chip devices to prevent diabetic metabolisms
Image recognition of multi-perspective data for intelligent analysis of gestures and actions
Get PDFThe BERMUDA project started in January 2015 and was successfully completed after less than three years in August 2017. A technical set-up and an image processing and analysis software were developed to record and evaluate multi-perspective videos. Based on two cameras, positioned relatively far from one another with tilted axes, synchronized videos were recorded in the laboratory and in real life. The evaluation comprised the background elimination, the body part classification, the clustering, the assignment to persons and eventually the reconstruction of the skeletons. Based on the skeletons, machine learning techniques were developed to recognize the poses of the persons and next for the actions performed. It was, for example, possible to detect the action of a punch, which is relevant in security issues, with a precision of 51.3 % and a recall of 60.6 %.Das Projekt BERMUDA konnte im Januar 2015 begonnen und nach knapp drei Jahren im August 2017 erfolgreich abgeschlossen werden. Es wurden ein technischer Aufbau und eine Bildverarbeitungs- und Analysesoftware entwickelt, mit denen sich multiperspektivische Videos aufzeichnen und auswerten lassen. Basierend auf zwei in größerem Abstand gewinkelt positionierten Kameras wurden synchrone Videos sowohl im Labor als auch in realen Umgebungen aufgenommen. Die Auswertung umfasst die Hintergrundeliminierung, die Körperteilklassifikation, ein Clustering, die Zuordnung zu Personen und schließlich die Rekonstruktion der Skelette. Ausgehend von den Skeletten wurden Methoden des maschinellen Lernens zur Erkennung der Haltungen und darauf aufbauend zur Gestenerkennung entwickelt. Beispielhaft konnte die im Sicherheitskontext relevante Handlung des Schlagens mit einer Genauigkeit von 51,3 % und einer Trefferquote von 60,6 % erkannt werden
Einsatz der Brennstoffzelle als Netzersatzanlage sicherheitsrelevanter Digitalfunkstationen im Feldtest
Get PDFEs wird anhand des Förderprojekts „Wasserstoff-Netzersatzanlagen der Behörden und Organisationen mit Sicherheitsaufgaben (BOS) des Landes Brandenburg“ des Zentraldienstes der Polizei des Landes Brandenburg die Praxistauglichkeit von Brennstoffzellen-Netzersatzanlagen untersucht. Marktreife und kommerziell verfügbare Brennstoffzellen wurden in 115 sicherheitsrelevanten Digitalfunkstationen im Flächenland Brandenburg als Ersatz von wartungsintensiven und umweltproblematischen Dieselgeneratoren für die (Not-)Stromversorgung installiert. Diese Netzersatzanlagen sind für eine Überbrückungszeit von 72 h unter realen Bedingungen ausgelegt und wurden im Feldtest, parallel zum realen Betrieb, über einen längeren Einsatzzeitraum (ca. 2 Jahre) auf ihre Zuverlässigkeit und Verfügbarkeit hin untersucht. Die Anforderungen an und die Realisierung der Brennstoffzellen-Netzersatzanlagen sowie die Feldtest-Versuchsplanung und deren Ergebnisse werden beschrieben und diskutiert. Die Praxistauglichkeit wird mit einer hohen Verfügbarkeit über 97 % und einer Funktionszuverlässigkeit von mehr als 95 % erfolgreich bestätigt. Die Entwicklung weiterer Komponenten wird empfohlen.On the basis of the funding project "Hydrogen Based Backup Power Systems of Public Authorities and Organizations with Security Tasks (BOS) of the German Federal State of Brandenburg" of the Central Police’s Services of the German Federal State of Brandenburg, the practicability of fuel-cell backup power systems is investigated. Within this project, market-ready and commercially available fuel-cell systems were installed in 115 security-relevant digital telecommunication units in the Federal State of Brandenburg as a replacement for maintenance-intensive and environmentally-hazardous diesel generators for (emergency) power supply. These emergency power systems are designed for a bridging time of 72 hours under real conditions and have been tested for their reliability and availability over a longer period of operation (approx. 2 years) in the field test, simultaneously with real operation. The requirements and realization of the fuel cell backup power systems as well as the field test planning and their results are described and discussed. The practicability is successfully confirmed with a high availability of more than 97 % and a functional reliability of more than 95 %. Additional development requirements for further components are recommended
(Teil-)Automatisierung eines Workflows zur Bewertung und Integration heterogener Datenbestände in eine Linked- Data-basierte Forschungsdateninfrastruktur
No full textDie Motivation für diese Arbeit entstand durch den ansteigenden Bedarf an Unterstützung bei der Datenverarbeitung innerhalb von Digital Humanities Projekten. Die vorliegende Masterarbeit hat das Ziel, den Workflow für die Datenintegration im Forschungsprojekt diggr in den Punkten Transparenz, Nachvollziehbarkeit, Wiederholbarkeit und Automatisierung zu verbessern. Diese Aspekte werden berücksichtigt, indem eine koordinierte Toolchain aufgebaut wird, die überwiegend mit dem Resource Description Framework (RDF) arbeitet. Innerhalb dieser Toolchain werden Datenqualitätsprüfungen durch ein formalisiertes Verfahren unterstützt. Zuvor werden Anwendungsfälle betrachtet, aus denen anschließend Anforderungen extrahiert und beschrieben werden. Danach folgt die Entwicklung und Implementierung der einzelnen Komponenten
Femtosecond-Pulsed Laser Written and Etched Fiber Bragg Gratings for Fiber-Optical Biosensing
No full textWe present the development of a label-free, highly sensitive fiber-optical biosensor for online detection and quantification of biomolecules. Here, the advantages of etched fiber Bragg gratings (eFBG) were used, since they induce a narrowband Bragg wavelength peak in the reflection operation mode. The gratings were fabricated point-by-point via a nonlinear absorption process of a highly focused femtosecond-pulsed laser, without the need of prior coating removal or specific fiber doping. The sensitivity of the Bragg wavelength peak to the surrounding refractive index (SRI), as needed for biochemical sensing, was realized by fiber cladding removal using hydrofluoric acid etching. For evaluation of biosensing capabilities, eFBG fibers were biofunctionalized with a single-stranded DNA aptamer specific for binding the C-reactive protein (CRP). Thus, the CRP-sensitive eFBG fiber-optical biosensor showed a very low limit of detection of 0.82 pg/L, with a dynamic range of CRP detection from approximately 0.8 pg/L to 1.2 µg/L. The biosensor showed a high specificity to CRP even in the presence of interfering substances. These results suggest that the proposed biosensor is capable for quantification of CRP from trace amounts of clinical samples. In addition, the adaption of this eFBG fiber-optical biosensor for detection of other relevant analytes can be easily realized