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This dissertation delves into fiber-optic multimode interference (MMI) sensing and imaging. Various MMI-based fiber sensors were developed and demonstrated, including square-core fiber and core-offset structure, which have shown significantly enhanced sensitivities for temperature and strain measurement. Additionally, an MMF imaging system incorporating deep learning was studied, which increases the practical applicability of MMF imaging systems by being resilient to thermal perturbations., Diese Arbeit befasst sich mit der faseroptischen Multimode-Interferenz (MMI) Messung und Abbildung. Dabei wurden verschiedene MMI-basierte Fasersensoren entwickelt und getestet, darunter optische Fasern mit square-core und core-offset Strukturen, welche eine höhere Empfindlichkeit für Temperatur- und Dehnungsmessungen aufweisen. Außerdem wurde ein MMF-Bildgebungssystem mit Deep Learning eingesetzt, das die praktische Anwendbarkeit erhöht, da es unempfindlich gegenüber thermischen Störungen ist.

This dissertation aims to design, develop, and qualify a fiber-optic pressure sensing system for harsh field testing environments. The proposed system consists of passive fiber-optic Fabry–Pérot pressure sensors and an edge filter interrogator. In addition to theoretical validation, experimental measurement campaigns in wind tunnel tests, flight tests, and wind turbines characterize the sensor’s performance., Ziel dieser Dissertation ist es, ein faseroptisches Drucksensorsystem für raue Feldtestumgebungen zu entwerfen, zu entwickeln und zu qualifizieren. Das vorgeschlagene System besteht aus passiven faseroptischen Fabry-Pérot-Drucksensoren und einem Kantenfilter-Abfragesystem. Neben der theoretischen Validierung charakterisieren experimentelle Messkampagnen in Windkanaltests, Flugtests und Windkraftanlagen die Leistung des Sensors.

Rotationsgeschwindigkeitsmessung ist von großer Bedeutung in Gebiete wie der Automobilindustrie oder erneuerbare Energie. Self-mixing Interferometry ist ein preiswerte und vielversprechende Messmethode, die präzise Messungen ermöglichen kann. Doch viele Herausforderungen wie Spektralverbreiterung erschweren genaue Messungen. In dieser Arbeit sind mithilfe von Korrelationsfunktionen neue Signalverarbeitungsmethoden entwickelt worden, mit denen diese Herausforderungen überwunden werden sollen., Rotational speed measurement is of great importance in many industries like automotive or renewable energy. Self-mixing interferometry is a very inexpensive promising non-contact measurement technology that can provide precise rotational speed measurement. But many challenges like spectral broadening complicate precise measurements significantly. In this work, new signal processing methods based on correlation functions have been developed to overcome these challenges.

Regenerated fiber Bragg gratings inscribed in large mode area fibers exhibit better high-temperature sensing performance and can be applied in harsh environments like metal casting. The evolutions and distributions of temperature and strain during aluminum and copper casting processes can be monitored by the fiber optic method. Fiber Bragg gratings can be embedded into metal structures for in-situ structural health monitoring by casting. With a single embedded sensing fiber, temperature and external strain can be measured and decoupled., Regenerierte Faser-Bragg-Gitter, die in Fasern mit großer Modenfläche eingeschrieben sind, weisen eine bessere Hochtemperatur-Erfassungsleistung auf und können in rauen Umgebungen wie Metallguss eingesetzt werden. Die Entwicklung und Verteilung von Temperatur und Dehnung während Aluminium- und Kupfergießprozessen kann durch die faseroptische Methode überwacht werden. Faser-Bragg-Gitter können durch Gießen in Metallstrukturen eingebettet werden, um den strukturellen Zustand vor Ort zu überwachen. Mit einer einzigen eingebetteten Sensorfaser können Temperatur und externe Dehnung gemessen und entkoppelt werden.

This thesis develops 4 novel common-path interferometric methods for single-shot quantitative phase imaging in the fields of speckle interferometry and digital holographic microscopy. All the methods are based on the off-axis interferometric configuration of common-path geometry, and therefore they offer both high imaging speeds (temporal resolution) and high temporal phase stability., In dieser Arbeit werden vier neuartige interferometrische Common-Path-Methoden für die quantitative Phasenabbildung in einem einzigen Schritt in den Bereichen Speckle-Interferometrie und digitale holografische Mikroskopie entwickelt. Alle Methoden basieren auf der achsenfernen interferometrischen Konfiguration der Common-Path-Geometrie und bieten daher sowohl hohe Abbildungsgeschwindigkeiten (zeitliche Auflösung) als auch hohe zeitliche Phasenstabilität.

The goal of this work is to develop a novel interferometric method for roughness measurement. Contrary to conventional approaches, the depolarization of the scattered light by the rough sample is considered, leading to a more accurate estimation of the roughness in the sub-wavelength domain and at the same time non-destructive and fast measurements. Compared to earlier works, the more general theory allows the application to other optical devices where depolarization of light occurs., Ziel dieser Arbeit ist, eine neue interferometrische Methode zur Rauheitsmessung zu entwickeln. Im Gegensatz zu herkömmlichen Ansätzen wird die Depolarisation des Streulichts durch die raue Probe berücksichtigt, was zu einer genaueren Schätzung der Rauheit im Sub-Wellenlängenbereich und zu zerstörungsfreien und schnellen Messungen führt. Verglichen mit früheren Arbeiten erlaubt die allgemeinere Theorie die Anwendung auf weitere optische Geräte, bei denen eine Depolarisierung des Lichts auftritt.

Die Lasertriangulation ist eine häufig verwendete Messmethode in der Industrie. Die hohe Anfälligkeit gegenüber Störungen, wie zum Beispiel der Verschiebung von Komponenten aufgrund einer thermischen Ausdehnung, stellt dabei ein großes Problem dar. Ziel dieser Arbeit ist es, durch eine optische Kompensation vielfältige Fehlerquellen zu eliminieren und somit die Messgenauigkeit zu steigern. Durch den Einsatz von strukturierten Messoberflächen wird die Empfindlichkeit des Lasertriangulationssystems zusätzlich erhöht und somit die Messabweichung weiter reduziert., Laser triangulation is a commonly used measurement method in industrial applications. Its strong susceptibility to errors, e.g., the movement of components due to a thermal expansion of the measurement device, is one of the main problems. The goal of this work is to increase the measurement accuracy by eliminating diverse error sources using an optical compensation setup. The sensitivity of the laser triangulation system can additionally be enhanced through the application of structured measurement surfaces, thus leading to a further reduction of the measurement deviation.

Für die Weiterentwicklung von Gasturbinen und Chemiereaktoren bedarf es neuartiger Sensoren, welche Hochtemperaturprofile mit einer hohen räumlichen Auflösung bei geringem Platzbedarf und Verkabelungsaufwand erfassen können. In diesem Rahmen bietet die faseroptische Multipunkt-Sensorik basierend auf regenerierten Faser-Bragg-Gittern (RFBG) und Wellenlängenmultiplexverfahren erhebliches Innovationspotenzial, da sie es erlaubt, etliche Temperatursensoren in eine einzige Messleitung zu integrieren., For the further development of gas turbines and chemical reactors, novel sensor types are needed capable of detecting high-temperature profiles with high spatial resolution at low space requirements and cabling efforts. In this context, fiber-optic multipoint sensing based on wavelength-multiplexed regenerated fiber Bragg gratings (RFBGs) offers significant improvements, as it allows several temperature sensors to be integrated in a single cable.

Für die Messung von Temperatur und Dehnung in Aluminiumgussbauteilen wurden Faser-Bragg-Gitter-(FBG) Sensoren entwickelt und verifiziert. Diese FBG Sensoren ermöglichten es beim Erstarrungsprozess und anschließend im Betrieb der Bauteile zu messen. Es wurde ein neues Verfahren zur einfachen Kalibrierung von Multipunkt-Temperatursensoren aus den Daten von Einzelpunkt-Temperatursensoren entwickelt. Das mechanische Verhalten der Glasfaser in einem Temperaturbereich von Raumtemperatur bis 900 °C wurde erstmals mittels regenerierten FBG (RFBG) untersucht., For the measurement of temperature and strain in casted aluminium parts, fiber Bragg grating (FBG) sensors were developed and verified. These FBG were able to measure during the solidification process and operation of the part. A new method for a simple calibration procedure for multi-point temperature sensors, based on the data of single-point temperature sensors, was developed. For the first time, the mechanical behaviour of an optical fiber was investigated with regenerated FBG (RFBG) in a temperature range from room temperature to 900 °C.

This work studies the suitability of hyperspectral imaging microscopy for rapid and accurate atomic layer mapping of two-dimensional (2D) materials. A hyperspectral imaging system including a line-scan hyperspectral imaging microscope, system control, data acquisition, and data processing was custom built. A manual interpretation method based on hyperspectral library and spectral unmixing was developed for layer maps reconstruction with one-atomic-layer resolution. A deep fusion neural network based on the U-Net architecture was proposed for fully automated large-area atomic layer mapping of 2D materials., Diese Arbeit untersucht die Eignung der hyperspektralen Bildgebungsmikroskopie für die schnelle und genaue Kartierung der Atomschicht zweidimensionaler (2D) Materialien. Ein hyperspektrales Bildgebungssystem mit einem Hyperspektralbildmikroskop mit Zeilenscan, Systemsteuerung, Datenerfassung und Datenverarbeitung wurde speziell angefertigt. Eine manuelle Interpretationsmethode basierend auf hyperspektraler Bibliothek und spektraler Entmischung wurde für die Rekonstruktion von Schichtkarten mit einer Auflösung von einer Atomschicht entwickelt. Für die vollautomatische großflächige atomare Schichtzuordnung wurde ein auf der U-Net-Architektur basierendes Deep Fusion Neural Network vorgeschlagen.

This thesis summarizes publications of prospective, non-interventional studies on the identification of novel biomarkers in critical care medicine. Biomarkers in the context of this thesis are laboratory values that are determined from the blood of patients who are treated on an intensive care unit. They are used in clinical routine for diagnosis, prognosticate and monitor treatment. For clinical applicability, biomarkers must have appropriate statistical test characteristics to enable distinction between different states of disease. Beyond that, biomarkers should be easy to obtain, rapidly measurable, and generalizable for instant interpretation in the clinical context and prompt decision making to favourably influence the course of the disease. The aim of this thesis was to evaluate the significance, regulation, diagnostic and prognostic value of novel biomarkers measured in the blood of critical ill patients.

Die Arbeit untersucht, welche Energieeinsparungen sich für automatisierte Fahrzeuge durch energieeffizientes Fahren und einen darauf optimierten, elektrischen Antriebsstrang ergeben. Dafür wird ein Algorithmus zum energieeffizienten Fahren für elektrische Antriebsstrangtopologien aufgebaut und im Anschluss in eine Antriebsstrangoptimierung integriert. Die Ergebnisse zeigen, dass eine Reduktion der Leistungsreserven, als auch das energieeffiziente Fahren, Einsparungen zulassen. Dabei kannibalisieren sich diese Maßnahmen., This work investigates the energy savings that can be achieved for automated vehicles through energy-efficient driving and an optimized electric powertrain. For this purpose, an algorithm for energy-efficient driving for electric powertrain topologies is developed and subsequently integrated into a powertrain optimization. The results show that a reduction of the power reserves as well as energy-efficient driving allow savings. However, these measures cannibalize each other.

Gaskonzentrationsmessungen in der Industrie und im urbanen Raum werden im Zuge aktueller Debatten immer wichtiger. Die Auswahl an hochselektiven und gleichzeitig gegenüber Umwelteinflüssen robusten Messsystemen für diese Bereiche ist jedoch überschaubar. Eine Alternative bietet die photoakustische Spektroskopie in Kombination mit einem statischen Michelson-Interferometer zur Gaskonzentrationsmessung. Aufgrund des differentiellen Verhaltens des Interferometers werden Druckschwankungen kompensiert, sodass Messungen im Gasfluss möglich sind. Eine Drift des Arbeitspunktes, u.a. hervorgerufen durch Temperaturschwankungen, wird durch ein Referenzsignal kompensiert. Der Funktionsnachweis wird anhand von NO2-Messungen bis Konzentrationen von maximal 500 ppm erbracht., Gas concentration measurements in the industry as well as in urban areas are becoming increasingly important in light of the current debates. However, the range of measuring systems in this area that are, on the one hand, highly selective and, on the other, robust against environmental influences is limited. Photoacoustic spectroscopy in combination with a static Michelson interferometer for gas concentration measurement offers a viable alternative. Due to the differential behavior of the interferometer, pressure fluctuations are compensated, so that measurements in the gas flow are possible. Any drift of the operating point, which is caused, among other things, by fluctuations in temperature, is compensated by a reference signal. The proof of concept is provided by NO2 measurements with concentrations of up to 500 ppm.

In dieser Arbeit wird ein vielseitiges breitbandiges Spektrometer für den mittleren Infrarotbereich vorgestellt. Durch einen robusten und kompakten Aufbau sowie hohe Messgeschwindigkeiten bieten sich vielfältige Anwendungsmöglichkeiten zur on-line Prozessmesstechnik und zur zeitaufgelösten Gasanalyse. Neben Konzepten zur Erhöhung der spektralen Auflösung und zur Langzeitstabilisierung des Messsystems wurde eine abbildende Variante des Spektrometers entwickelt und validiert., In this thesis, a versatile broadband spectrometer for the mid-infrared spectral range is presented. Due to a robust and compact design as well as high measurement rates, a wide range of applications for on-line process monitoring and time-resolved gas analysis is feasible. In addition to concepts for increasing the spectral resolution and the long-term stability of the measurement device, a hyperspectral imaging version of the spectrometer was developed and validated.

This work studies the suitability of hyperspectral imaging microscopy for rapid and accurate atomic layer mapping of two-dimensional (2D) materials. A hyperspectral imaging system including a line-scan hyperspectral imaging microscope, system control, data acquisition, and data processing was custom built. A manual interpretation method based on hyperspectral library and spectral unmixing was developed for layer maps reconstruction with one-atomic-layer resolution. A deep fusion neural network based on the U-Net architecture was proposed for fully automated large-area atomic layer mapping of 2D materials., Diese Arbeit untersucht die Eignung der hyperspektralen Bildgebungsmikroskopie für die schnelle und genaue Kartierung der Atomschicht zweidimensionaler (2D) Materialien. Ein hyperspektrales Bildgebungssystem mit einem Hyperspektralbildmikroskop mit Zeilenscan, Systemsteuerung, Datenerfassung und Datenverarbeitung wurde speziell angefertigt. Eine manuelle Interpretationsmethode basierend auf hyperspektraler Bibliothek und spektraler Entmischung wurde für die Rekonstruktion von Schichtkarten mit einer Auflösung von einer Atomschicht entwickelt. Für die vollautomatische großflächige atomare Schichtzuordnung wurde ein auf der U-Net-Architektur basierendes Deep Fusion Neural Network vorgeschlagen.

Even though Fluorescence Imaging has unlocked new imaging possibilities in surgical guidance, there are still challenges that need to be addressed. The first challenge is related to the lack of calibration and standardization of the fluorescence imaging systems and the second one is related to the distortion of the fluorescence signal due to tissue scattering and absorption. The aim of this work is to propose novel solutions to overcome these challenges., Obwohl die Fluoreszenzbildgebung neue Bildgebungsmöglichkeiten in der chirurgischen Führung eröffnet hat, gibt es immer noch Herausforderungen, die angegangen werden müssen. Die erste Herausforderung betrifft das Fehlen einer Kalibrierung und Standardisierung der Fluoreszenzbildgebungssysteme, und die zweite betrifft die Verzerrung des Fluoreszenzsignals aufgrund von Gewebestreuung und Absorption. Ziel dieser Arbeit ist es, neue Lösungen vorzuschlagen um diese Herausforderungen zu bewältigen.

S1P and its receptors have been reported to play important roles in the development of renal fibrosis. Although S1P5 has barely been investigated so far, there are indications that it can influence inflammatory and fibrotic processes. Here, we report the role of S1P5 in renal inflammation and fibrosis. Male S1P5 knockout mice and wild-type mice on a C57BL/6J background were fed with an adenine-rich diet for 7 days or 14 days to induce tubulointerstitial fibrosis. The kidneys of untreated mice served as respective controls. Kidney damage, fibrosis, and inflammation in kidney tissues were analyzed by real-time PCR, Western blot, and histological staining. Renal function was assessed by plasma creatinine ELISA. The S1P5 knockout mice had better renal function and showed less kidney damage, less proinflammatory cytokine release, and less fibrosis after 7 days and 14 days of an adenine-rich diet compared to wild-type mice. S1P5 knockout ameliorates tubular damage and tubulointerstitial fibrosis in a model of adenine-induced nephropathy in mice. Thus, targeting S1P5 might be a promising goal for the pharmacological treatment of kidney diseases.

Card-based protocols allow to evaluate an arbitrary fixed Boolean function f on a hidden input to obtain a hidden output, without the executer learning anything about either of the two (e.g., [12]). We explore the case where f implements a universal function, i.e., f is given the encoding (P) of a program P and an input x and computes f(< P >,x) = P(x). More concretely, we consider universal circuits, Turing machines, RAM machines, and branching programs, giving secure and conceptually simple card-based protocols in each case. We argue that card-based cryptography can be performed in a setting that is only very weakly interactive, which we call the surveillance model. Here, when Alice executes a protocol on the cards, the only task of Bob is to watch that Alice does not illegitimately turn over cards and that she shuffles in a way that nobody knows anything about the total permutation applied to the cards. We believe that because of this very limited interaction, our results can be called program obfuscation. As a tool, we develop a useful sub-protocol sort(Pi)-X up arrow Y that couples the two equal-length sequences X, Y and jointly and obliviously permutes them with the permutation pi is an element of Pi that lexicographically minimizes pi(X). We argue that this generalizes ideas present in many existing card-based protocols. In fact, AND, XOR, bit copy [37], coupled rotation shuffles [30] and the permutation division protocol of [22] can all be expressed as coupled sort protocols.

Although deep reinforcement learning has recently been very successful at learning complex behaviors, it requires a tremendous amount of data to learn a task. One of the fundamental reasons causing this limitation lies in the nature of the trial-and-error learning paradigm of reinforcement learning, where the agent communicates with the environment and progresses in the learning only relying on the reward signal. This is implicit and rather insufficient to learn a task well. On the contrary, humans are usually taught new skills via natural language instructions. Utilizing language instructions for robotic motion control to improve the adaptability is a recently emerged topic and challenging. In this paper, we present a meta-RL algorithm that addresses the challenge of learning skills with language instructions in multiple manipulation tasks. On the one hand, our algorithm utilizes the language instructions to shape its interpretation of the task, on the other hand, it still learns to solve task in a trial-and-error process. We evaluate our algorithm on the robotic manipulation benchmark (Meta-World) and it significantly outperforms state-of-the-art methods in terms of training and testing task success rates. Codes are available at \url{https://tumi6robot.wixsite.com/million}.

OBJECTIVES: To improve colorectal cancer (CRC) survival and lower incidence rates, colonoscopy and/or fecal immunochemical test screening are widely implemented. Although candidate DNA methylation biomarkers have been published to improve or complement the fecal immunochemical test, clinical translation is limited. We describe technical and methodological problems encountered after a systematic literature search and provide recommendations to increase (clinical) value and decrease research waste in biomarker research. In addition, we present current evidence for diagnostic CRC DNA methylation biomarkers. METHODS: A systematic literature search identified 331 diagnostic DNA methylation marker studies published before November 2020 in PubMed, EMBASE, Cochrane Library, and Google Scholar. For 136 bodily fluid studies, extended data extraction was performed. STARD criteria and level of evidence were registered to assess reporting quality and strength for clinical translation. RESULTS: Our systematic literature search revealed multiple issues that hamper the development of DNA methylation biomarkers for CRC diagnosis, including methodological and technical heterogeneity and lack of validation or clinical translation. For example, clinical translation and independent validation were limited, with 100 of 434 markers (23%) studied in bodily fluids, 3 of 434 markers (0.7%) translated into clinical tests, and independent validation for 92 of 411 tissue markers (22%) and 59 of 100 bodily fluids markers (59%). DISCUSSION: This systematic literature search revealed that major requirements to develop clinically relevant diagnostic CRC DNA methylation markers are often lacking. To avoid the resulting research waste, clinical needs, intended biomarker use, and independent validation should be better considered before study design. In addition, improved reporting quality would facilitate meta-analysis, thereby increasing the level of evidence and enabling clinical translation.

In this thesis a novel and versatile phase modulator is proposed, which is based on the dual transverse electro-optic effect. The modulator is compatible with distinct interferometric systems. A linearly time-varying phase shift is generated between the interfering waves. To demonstrate the feasibility and compatibility of the modulator, three typical representatives of interferometric systems are configured, namely an interferometer, a holography system, and a differential microscope. The physical principle and the experiment verification are demonstrated in detail., In dieser Arbeit wird ein neuartiger und vielseitiger Phasenmodulator vorgeschlagen, der auf dem dual-transversalen elektrooptischen Effekt basiert. Der Modulator ist kompatibel mit verschiedenen interferometrischen Systemen. Zwischen den Interferenzwellen wird eine linear zeitvariable Phasenverschiebung erzeugt. Um die Machbarkeit und Kompatibilität des Modulators zu demonstrieren, werden drei typische exemplarische interferometrische Systeme konfiguriert, nämlich ein Interferometer, ein Holographiesystem und ein Differenzmikroskop. Das physikalische Prinzip und die experimentelle Verifikation werden im Detail erklärt.

Die vorliegende Arbeit stellt die Entwicklung, Evaluierung und den Vergleich neuartiger faseroptischer Schadensdetektionssysteme für Stromversorgungskabel vor. Die im Kabelgeflecht angeordneten Sensoren können unabhängig von der Energieübertragung des Stromversorgungskabels betrieben werden und bieten im Fall eines Kabelschadens das Potenzial, die Schadenslokalisierungsdauer signifikant abzusenken, was eine klare Kostenersparnis für die Kabelbetreiber darstellt., In this work, the development, evaluation, and comparison of novel fiber optic damage detection systems for power supply cables are presented. The sensors arranged in the cable braiding can be operated independently of the power transmission of the power supply cable and offer the potential to significantly reduce the damage localization time in case of cable damages, which represents clear cost savings for the cable operators.

A common method to measure the shape of optically rough surfaces is the Electronic Speckle-Pattern Interferometry (ESPI). In ESPI, the shape is reconstructed by means of characteristic fringe patterns which are similar to a contour map. In the event that the combination of the surface shape and the measuring wavelengths results in either too high or too low local fringe densities, ESPI is at its limits. By using wavefront generators, the fringe density of the fringe pattern can be manipulated locally. In the present study, the physical limits and the feasibility of this method are analyzed theoretically and experimentally., Die elektronische Speckle-Pattern Interferometrie (ESPI) ist eine verbreitete Methode für die Formvermessung von optisch rauen Oberflächen. Die Form wird hier aus Streifenmustern, ähnlich einer Höhenlinienkarte, rekonstruiert. Wenn durch die Kombination der Oberflächenform und der Messwellenlängen lokal entweder zu hohe oder zu niedrige Streifendichten entstehen, stößt die ESPI an ihre Grenzen. Durch den Einsatz von Wellenfrontgeneratoren können die Streifenmuster manipuliert und die Streifendichte lokal angepasst werden. In dieser Arbeit werden die physikalischen Grenzen und die Machbarkeit dieser Methode theoretisch und experimentell analysiert.

Zwei Konzepte zur dehnungskompensierten Temperaturmessung mit Faser-Bragg-Gitter-Sensoren (FBG) wurden für die Anwendung in Hochleistungsgeneratoren entwickelt und evaluiert. Reibungskraftunabhängige Temperaturmessungen konnten mit Unsicherheiten unter 1°C für eine 10 m lange FBG-Messleitung im Temperaturbereich zwischen -30°C und 125°C sichergestellt werden. Ein Verfahren zur querkraftkompensierten Temperatur-Dehnungs-Entkopplung ermöglichte erstmalig Temperaturmessungen mit einem vollständig oberflächenverklebten FBG-Sensorelement im Temperaturbereich zwischen -30°C und 110°C., Two concepts for strain compensated temperature measurements based on fiber Bragg gratings (FBG) have been developed for application in high power generators. Friction compensated temperature measurements were achieved in a temperature range between -30°C and 125°C with uncertainties less than 1°C using a measuring cable of 10 m length. A technique for decoupling temperature and strain, while additionally compensating transversal forces, enabled temperature measurements in a temperature range between -30°C und 110°C by using a surface-attached FBG sensor element for the first time.

Die in Motoren und Getrieben eingesetzten Schmieröle unterliegen aufgrund der hohen Belastung im Betrieb einem natürlichen Alterungsprozess. Der Ölzustand muss daher regelmäßig kontrolliert werden. Im Rahmen dieser Arbeit wurden Sensoren auf Basis der nicht-dispersiven Infrarotspektroskopie entwickelt, die direkt in ölführenden Anlagen installiert werden können und somit eine quasi-kontinuierliche Überwachung des Ölzustandes ermöglichen. Durch die Kalibration der Sensoren mit Hilfe von multivariaten Verfahren konnte eine hohe Korrelation zwischen den Messwerten der Sensoren und Referenzdaten genormter Ölzustandsparameter erzielt werden., The lubricating oils used in engines and transmissions are subject to a natural aging process due to their high load during operation. The oil condition must therefore be checked regularly. Within the scope of this work, sensors based on non-dispersive infrared spectroscopy were developed which can be installed directly in oil-bearing systems and thus enable a quasi-continuous monitoring of the oil condition. Using multivariate methods to calibrate the sensors, a high correlation between the measured values of the sensors and reference data of standardized oil condition parameters was achieved.

In this thesis a novel phase-shifting technique, "Adjustable Aperture Multiplexing (AAM)", was developed by multiplexing construction of virtual single apertures to produce tunable spatial carrier frequencies to recorded interferograms. It overcomes the main drawbacks of the existing phase-shifting techniques and offers competitive advantages. Meanwhile, three exemplary measurements were made to verify the AAM technique, including simultaneous out-of-plane displacement-slope measurement, in-plane rotation angular measurement, and 3D displacement measurement., In dieser Arbeit wurde eine neuartige Phasenverschiebungstechnik, "Adjustable Aperture Multiplexing (AAM)", durch eine Multiplex-Konstruktion von virtuellen Aperturen entwickelt, um einstellbare räumliche Trägerfrequenzen zu generieren. Es überwindet die Nachteile der vorhandenen Phasenverschiebungstechniken und bietet Wettbewerbsvorteile an. Um die AAM-Technik zu verifizieren wurden drei Messungen durchgeführt, inkl. simultaner Messung der out-of-plane Deformation und Deformationsgradient, in-plane Drehwinkelmessung und 3D-Deformationsmessung.

The WoodCluster project (2017-2021) focused on national bio-economies based on farm wood production in East African Countries. The project consortium was a South-South-North network with partners from Ethiopia, Tanzania, Uganda and Germany. In the project, the dynamics and resulting problems of an increasing wood supply gap, and possible solutions were investigated. The project had two main components: research and teaching. As an output of the teaching component, this trainer manual was developed for wood-based value chain actors in Ethiopia. This trainer manual aims to combine the theory of value chain development with participatory teaching methods and integrate this approach into extensions services linked to wood-based value chain actors in Ethiopia, thereby supporting their sustainable development. It especially intends to provide these trainers with insights into value chain development (VCD) tools and participatory knowledge transfer methods. The focus will be on participatory VCD approaches relevant to wood-based value chain actors. With the trainer manual, officers and trainers will be able to apply participatory VCD trainings to wood-based value chain actors in a Training of Trainers (ToT) session. Since these value chains and actors can vary depending on the regional setting, the raw material or end-product of interest, the defined scope, or the value chain development goals, the ToT will teach several approaches on the basis of which the officers and trainers can design suitable participatory VCD workshops. The trainer manual serves as a reference guide for trainers, who conduct participatory trainings, and extension agents linked to wood-based value chains in Ethiopia. The manual is constructed and arranged in such a way, so that a wide range of trainers with different skill levels and capacities may apply the participatory training in different conditions. Rather than presenting one appropriate teaching method, the manual presents several that allows

Objective Obesity is a negative prognostic factor for various clinical conditions. In this observational cohort study, we evaluated a CT-based assessment of the adipose tissue distribution as a potential non-invasive prognostic parameter in critical illness. Methods Routine CT-scans upon admission to the intensive care unit (ICU) were used to analyze the visceral and subcutaneous adipose tissue areas at the 3(rd) lumbar vertebra in 155 patients. Results were correlated with various prognostic markers and both short-term- and overall survival. Multiple statistical tools were used for data analysis. Results We observed a significantly larger visceral adipose tissue area in septic patients compared to non-sepsis patients. Interestingly, patients requiring mechanical ventilation had a significantly higher amount of visceral adipose tissue correlating with the duration of mechanical ventilation. Moreover, both visceral and subcutaneous adipose tissue area significantly correlated with several laboratory markers. While neither the visceral nor the subcutaneous adipose tissue area was predictive for short-term ICU survival, patients with a visceral adipose tissue area above the optimal cut-off (241.4 cm(2)) had a significantly impaired overall survival compared to patients with a lower visceral adipose tissue area. Conclusions Our study supports a prognostic role of the individual adipose tissue distribution in critically ill patients. However, additional investigations need to confirm our suggestion that routine CT-based assessment of adipose tissue distribution can be used to yield further information on the patients' clinical course. Moreover, future studies should address functional and metabolic analysis of different adipose tissue compartments in critical illness.

In dieser Arbeit wird ein vielseitiges breitbandiges Spektrometer für den mittleren Infrarotbereich vorgestellt. Durch einen robusten und kompakten Aufbau sowie hohe Messgeschwindigkeiten bieten sich vielfältige Anwendungsmöglichkeiten zur on-line Prozessmesstechnik und zur zeitaufgelösten Gasanalyse. Neben Konzepten zur Erhöhung der spektralen Auflösung und zur Langzeitstabilisierung des Messsystems wurde eine abbildende Variante des Spektrometers entwickelt und validiert., In this thesis, a versatile broadband spectrometer for the mid-infrared spectral range is presented. Due to a robust and compact design as well as high measurement rates, a wide range of applications for on-line process monitoring and time-resolved gas analysis is feasible. In addition to concepts for increasing the spectral resolution and the long-term stability of the measurement device, a hyperspectral imaging version of the spectrometer was developed and validated.

In dieser Arbeit wird der Aufbau eines analogen, breitbandigen Radarzielsimulators für radial bewegte Ziele in automobilen Radaranwendungen beschrieben. Zuerst wird ein Überblick über die Parameter aktueller automobiler Radarsensoren sowie die verschiedenen Ansätze der Radarzielsimulation gegeben. Anschließend werden daraus Anforderungen an einen Radarzielsimulator aufgestellt und durch praktische Limitierungen bedingte Abweichungen des simulierten Ziels von einem echten Ziel untersucht., In this thesis, the design of an analog, broadband radar target simulator for radial moving targets in automotive radar applications is described. First, an overview of current automotive radar sensor parameters as well as the various approaches to radar target simulation are given. Afterwards, requirements for a radar target simulator are thereof established and deviations due to practical limitations of the simulated target from a real target are examined.

In dieser Arbeit wurde der Wellenlängenbereich von oberflächenemittierenden Lasern auf GaSb-Basis mittels Typ II Quantentöpfen erweitert. Die entwickelten Laser emittieren bis zu 4 um und arbeiten dabei im Puls- und im Dauerstrichbetrieb (CW) bis 45°C bzw. -7°C. Die maximale Single-Mode-CW-Ausgangsleistung beträgt 0.175 mW. Es wird eine elektronisch-thermische Abstimmung von ~19 nm ohne Modensprünge erreicht. Diese neuartigen Laser sind sehr vielversprechend für Anwendungen in der Gassensorik., In this work the wavelength range of GaSb-based buried tunnel junction vertical-cavity surface-emitting lasers (VCSELs) has been extended using type-II quantum wells. The developed VCSELs emit up to 4 um and operate in continuous-wave (CW) and pulsed mode until -7°C and 45°C, respectively. The maximum single-mode CW output power is 0.175 mW. A mode-hop free electro-thermal tuning of ~19 nm is achieved. These first of a kind VCSELs are highly promising for gas sensing applications.

This dissertation provides an efficient and tuning-easy fixed gain filter to obtain the velocity in electrical drives by analyzing the shaft position signal from the optical encoder. With employing the laser self-mixing interferometry, algorithms in an attempt to increase the accuracy of velocity measurement are thoroughly investigated and fully detailed; while the algorithms for retrieving displacement are improved by proposing the extended Kalman filter and a simple method for estimating the feedback factor C., Der vorliegenden Dissertation vorschlagt ein effizientes und einfach einzustellendes Filter mit fester Verstärkung, um die Geschwindigkeit durch die Analyse des Positionssignals vom optischen Encoder zu erhalten. Bei der Verwendung der Self-Mixing-Interferometrie werden die Algorithmen zur Erhöhung der Genauigkeit in der Geschwindigkeitsmessung gründlich untersucht und ausführlich dargelegt. Währenddessen wird die Algorithmen zur Verschiebungsbestimmung verbessert, indem das Erweiterte Kalman-Filter und eine einfache Methode zur Schätzung des Rückkopplungsfaktors C vorgeschlagen wird.

Cutaneous T cell lymphomas (CTCLs) represent a heterogeneous group of T cell lymphomas that primarily affect the skin. The most frequent forms of CTCL are mycosis fungoides and Sézary syndrome. Both are characterized by frequent recurrence, developing chronic conditions and high mortality with a lack of a curative treatment. In this study, we evaluated the effect of short-chain, cell-permeable C6 Ceramide (C6Cer) on CTCL cell lines and keratinocytes. C6Cer significantly reduced cell viability of CTCL cell lines and induced cell death via apoptosis and necrosis. In contrast, primary human keratinocytes and HaCaT keratinocytes were less affected by C6Cer. Both keratinocyte cell lines showed higher expressions of ceramide catabolizing enzymes and HaCaT keratinocytes were able to metabolize C6Cer faster and more efficiently than CTCL cell lines, which might explain the observed protective effects. Along with other existing skin-directed therapies, C6Cer could be a novel well-tolerated drug for the topical treatment of CTCL.

In dieser Arbeit wird der Aufbau eines analogen, breitbandigen Radarzielsimulators für radial bewegte Ziele in automobilen Radaranwendungen beschrieben. Zuerst wird ein Überblick über die Parameter aktueller automobiler Radarsensoren sowie die verschiedenen Ansätze der Radarzielsimulation gegeben. Anschließend werden daraus Anforderungen an einen Radarzielsimulator aufgestellt und durch praktische Limitierungen bedingte Abweichungen des simulierten Ziels von einem echten Ziel untersucht., In this thesis, the design of an analog, broadband radar target simulator for radial moving targets in automotive radar applications is described. First, an overview of current automotive radar sensor parameters as well as the various approaches to radar target simulation are given. Afterwards, requirements for a radar target simulator are thereof established and deviations due to practical limitations of the simulated target from a real target are examined.

This dissertation provides an efficient and tuning-easy fixed gain filter to obtain the velocity in electrical drives by analyzing the shaft position signal from the optical encoder. With employing the laser self-mixing interferometry, algorithms in an attempt to increase the accuracy of velocity measurement are thoroughly investigated and fully detailed; while the algorithms for retrieving displacement are improved by proposing the extended Kalman filter and a simple method for estimating the feedback factor C., Der vorliegenden Dissertation vorschlagt ein effizientes und einfach einzustellendes Filter mit fester Verstärkung, um die Geschwindigkeit durch die Analyse des Positionssignals vom optischen Encoder zu erhalten. Bei der Verwendung der Self-Mixing-Interferometrie werden die Algorithmen zur Erhöhung der Genauigkeit in der Geschwindigkeitsmessung gründlich untersucht und ausführlich dargelegt. Währenddessen wird die Algorithmen zur Verschiebungsbestimmung verbessert, indem das Erweiterte Kalman-Filter und eine einfache Methode zur Schätzung des Rückkopplungsfaktors C vorgeschlagen wird.

Brain monitoring; Electrochemical sensors; Fiber-optic sensors; Intracranial sensors; Microdialysis, Fundamental Research Funds for the Central Universities; Royal Society

Colorimetric tests for at-home health monitoring became popular 50 years ago with the advent of the urinalysis test strips, due to their reduced costs, practicality, and ease of operation. However, developing digital systems that can interface these sensors in an efficient manner remains a challenge. Efforts have been put towards the development of portable optical readout systems, such as smartphones. However, their use in daily settings is still limited by their error-prone nature associated to optical noise from the ambient lighting, and their low sensitivity. Here, a smartphone application (Colourine) to readout colorimetric signals was developed on Android OS and tested on commercial urinalysis test strips for pH, proteins, and glucose detection. The novelty of this approach includes two features: a pre-calibration step where the user is asked to take a photo of the commercial reference chart, and a CIE-RGB-to-HSV color space transformation of the acquired data. These two elements allow the background noise given by environmental lighting to be minimized. The sensors were characterized in the ambient light range 100-400 lx, yielding a reliable output. Readouts were taken from urine strips in buffer solutions of pH (5.0-9.0 units), proteins (0-500 mg dL(-1)) and glucose (0-1000 mg dL(-1)), yielding a limit of detection (LOD) of 0.13 units (pH), 7.5 mg dL(-1) (proteins) and 22 mg dL(-1) (glucose), resulting in an average LOD decrease by about 2.8 fold compared to the visual method., Engineering and Physical Sciences Research Council (EPSRC) New Investigator Award; Central Universities Fundamental Research Funds; KU-KAIST Joint Research Center; Sandooq Al Watan LLC (SWARD)

Switzerland is undergoing a curricular change. Curriculum 21 has been ratified by all 21 German-speaking and is currently being implemented. With this innovation, German-speaking Switzerland will move toward a more technology-oriented education. What has been Manual Training or Wood/ Metalwork Classes is now replaced by composite subjects such as Nature and Technology. These subjects now structurally anchor technology-oriented content at the compulsory school level (Stuber, Heitzmann, & Käser, 2013) and are supposed to be implemented in the sense of the Anglo-Saxon concept of Science – Technology – Society – Environment (Labudde, 2012, p. 86). The technology orientation includes an instructional orientation toward a technical understanding or understanding technology, which, eo ipso, needs to be part of teacher education programs (Keller, 2017). To put things bluntly: Who else than technology/ technics-oriented teachers should teach technology and technics? Yet, technics or technology is not explicitly part of their initial studies, perhaps because in “the mandatory school, i.e. K-12, there is no specific subject ‘Technology’, but there is a subject called ‘Textile and Technical Design’” (Kruse & Labudde, 2016, p. 62). Therefore, student teachers may at the most specialize in textile and technical design or in information technology/ computer science and teach technics and technology in an integrated way. But what are factors they would consider to impede tech instruction? In other words: What are factors that hinder high quality technology instruction by means of teacher beliefs? In this presentation we will give insights to a quantitative exploratory study.

The N-Myc Downstream-Regulated Gene 4 (NDRG4), a prominent biomarker for colorectal cancer (CRC), is specifically expressed by enteric neurons. Considering that nerves are important members of the tumor microenvironment, we here establish different Ndrg4 knockout (Ndrg4−/−) CRC models and an indirect co-culture of primary enteric nervous system (ENS) cells and intestinal organoids to identify whether the ENS, via NDRG4, affects intestinal tumorigenesis. Linking immunostainings and gastrointestinal motility (GI) assays, we show that the absence of Ndrg4 does not trigger any functional or morphological GI abnormalities. However, combining in vivo, in vitro, and quantitative proteomics data, we uncover that Ndrg4 knockdown is associated with enlarged intestinal adenoma development and that organoid growth is boosted by the Ndrg4−/− ENS cell secretome, which is enriched for Nidogen-1 (Nid1) and Fibulin-2 (Fbln2). Moreover, NID1 and FBLN2 are expressed in enteric neurons, enhance migration capacities of CRC cells, and are enriched in human CRC secretomes. Hence, we provide evidence that the ENS, via loss of Ndrg4, is involved in colorectal pathogenesis and that ENS-derived Nidogen-1 and Fibulin-2 enhance colorectal carcinogenesis.

Post-transcriptional modifications of RNA constitute an emerging regulatory layer of gene expression. The demethylase fat mass- and obesity-associated protein (FTO), an eraser of N6-methyladenosine (m6A), has been shown to play a role in cancer, but its contribution to tumor progression and the underlying mechanisms remain unclear. Here, we report widespread FTO downregulation in epithelial cancers associated with increased invasion, metastasis and worse clinical outcome. Both in vitro and in vivo, FTO silencing promotes cancer growth, cell motility and invasion. In human-derived tumor xenografts (PDXs), FTO pharmacological inhibition favors tumorigenesis. Mechanistically, we demonstrate that FTO depletion elicits an epithelial-to-mesenchymal transition (EMT) program through increased m6A and altered 3'-end processing of key mRNAs along the Wnt signaling cascade. Accordingly, FTO knockdown acts via EMT to sensitize mouse xenografts to Wnt inhibition. We thus identify FTO as a key regulator, across epithelial cancers, of Wnt-triggered EMT and tumor progression and reveal a therapeutically exploitable vulnerability of FTO-low tumors., SCOPUS: ar.j, info:eu-repo/semantics/published

In dieser Arbeit wird ein neuartiges Spektrometer-Konzept für den Infrarotbereich vorgestellt, theoretisch modelliert und evaluiert. Das statische Einzelspiegel-Fourier-Transformations-Infrarotspektrometer weist eine hohe Étendue, keine prinzipbedingten internen Lichtverluste sowie ein einfaches statisches Design ohne bewegliche Teile auf. So ermöglicht es spektrale Messungen im mittleren infraroten Wellenlängenbereich mit hoher Messgeschwindigkeit und Robustheit., In this work, a novel spectrometer concept for the infrared is presented, theoretically modeled, and evaluated. The static single-mirror Fourier transform infrared spectrometer features a high etendue, no inherent internal light losses as well as a simple static design without any moving parts. Therefore, it enables spectral measurements in the mid-infrared wavelength region with high measurement speed and ruggedness.

Immer größer werdende Windenergieanlagen stellen den Maschinenbau vor große Herausforderungen im Umgang mit mechanischen Lasten. Durch aktive Lastreduktion kann der Bau von größeren und effizienteren Windenergieanlagen ermöglicht werden. Faseroptische Messtechnik bietet hierfür das Potential die Lasten in den Rotorblättern zuverlässig zu erfassen. In dieser Arbeit wurde die Zuverlässigkeit und die Industrietauglichkeit der Messtechnik in umfangreichen Labor-, Prüfstands-, und Feldtests nachgewiesen., Upscaling wind energy converters challenge engineering in handling growing mechanical loads. Using active load reduction technique enables the construction of bigger and more efficient wind energy converters. Fiber optic measurement technology delivers the potential for reliable blade load measurement. In this thesis the measurement technology is verified in laboratory, test stand, and field regarding reliability and suitability for industrial applications.

Faser-Bragg-Gitter (FBGs) werden durch ihre Vorteile gegenüber elektrischen Sensoren vermehrt zur Strukturüberwachung angewandt. In dieser Arbeit wurde die Anwendbarkeit von eingebetteten FBGs im Bereich des Gießereiwesens und der Gebäudeüberwachung untersucht. Es konnte gezeigt werden, dass FBGs den hohen Temperaturen beim Bauteilguss standhalten und eine Überwachung des Herstellungsprozess ermöglichen. Im Bereich der Gebäudeüberwachung wurde eine Sensoranordnung entwickelt, die nachträglich und minimal-invasiv in ein Mauerwerk eingebettet werden kann. Mit dieser können lokale Dehnungen und Temperaturen ermittelt werden., The use of Fiber-Bragg-Gratings (FBGs) in the field of structural health monitoring increases due to their advantage over electric sensors. In this work the applicability of embedded FBGs in the field of foundries and building monitoring was evaluated. It was shown that FBGs can withstand the high temperatures used in foundries and enable a monitoring of the fabrication process. In the area of building monitoring a sensor arrangement was developed which allows a subsequent and minimal-invasive installation into the stonework. Local temperatures and stresses can be detected with this arrangement.

The thesis focuses on the development of a fiber-optical measurement system using FBG sensors for temperature measurements for space applications. The interrogation technique is based on a tunable laser concept (modulated-grating Y-branch laser). The extreme conditions in space environment (temperature and radiation), required detailed analysis. Thermal test results of FBG sensors using the developed interrogator illustrate that the performance goal of measurement accuracy of +/- 1°C is achieved., Das entwickelte faser-optische Messsystem ist für den Einsatz in Weltraummissionen konzipiert. Das Messsystem basiert auf einer durchstimmbaren Lichtquelle (Modulated-Grating Y-Branch Laser). Aufgrund der extremen Umgebungsbedingungen für Systeme im Weltraum (Temperaturdifferenzen, hohe Strahlenbelastungen), wird eine detaillierte Analyse durchgeführt. Thermaltests der FBG Sensoren, gemessen mit dem entwickelten Messsystem, zeigen das Erreichen der geforderten Messgenauigkeit von +/- 1°C.

A new layered mesoporous Zr-MOF of composition [Zr30O20(OH)26(OAc)18L18] was synthesized by employing 5-acetamidoisophthalic acid (H2L) using acetic acid as the solvent. The new MOF, denoted as CAU-45, exhibits a honeycomb structure of stacked layers which comprise both hexa- and dodecanucelar zirconium clusters. Its structure was solved from submicrometer-sized crystals by continuous rotation electron diffraction (cRED). Liquid phase exfoliation and size selection were successfully performed on the material.

This thesis presents a method for measuring the refractive index with fibre optic Fresnel sensors. The applied calibration procedure is described and two models are proposed to measure the degree of cure and viscosity of curing thermosetting epoxy resin. The models are based on the resin refractive index and its temperature. The applicability of the measurement system and the models is shown in the production of composite materials., Diese Arbeit stellt eine Methode zur Messung des Brechungsindexes mit faseroptischen Fresnelsensoren vor. In der Arbeit wird das angewandte Kalibrierungsverfahren beschrieben, sowie zwei Modelle vorgeschlagen, um den Aushärtungsgrad und die Viskosität des aushärtenden duroplastischen Epoxidharzes zu messen. Die Modelle basieren auf dem Brechungsindex und der Temperatur des Harzes. Die Anwendbarkeit des Messsystems und der Modelle wird bei der Herstellung von Verbundwerkstoffen gezeigt.