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The field of optical lithography is subject to intense research and has gained enormous improvement. However, the effort necessary for creating structures at the size of 20 nm and below is considerable using conventional technologies. This effort and the resulting financial requirements can only be tackled by few global companies and thus a paradigm change for the semiconductor industry is conceivable: custom design and solutions for specific applications will dominate future development (Fritze in: Panning EM, Liddle JA (eds) Novel patterning technologies. International society for optics and photonics. SPIE, Bellingham, 2021. 10.1117/12.2593229). For this reason, new aspects arise for future lithography, which is why enormous effort has been directed to the development of alternative fabrication technologies. Yet, the technologies emerging from this process, which are promising for coping with the current resolution and accuracy challenges, are only demonstrated as a proof-of-concept on a lab scale of several square micrometers. Such scale is not adequate for the requirements of modern lithography; therefore, there is the need for new and alternative cross-scale solutions to further advance the possibilities of unconventional nanotechnologies. Similar challenges arise because of the technical progress in various other fields, realizing new and unique functionalities based on nanoscale effects, e.g., in nanophotonics, quantum computing, energy harvesting, and life sciences. Experimental platforms for basic research in the field of scale-spanning nanomeasuring and nanofabrication are necessary for these tasks, which are available at the Technische Universität Ilmenau in the form of nanopositioning and nanomeasuring (NPM) machines. With this equipment, the limits of technical structurability are explored for high-performance tip-based and laser-based processes for enabling real 3D nanofabrication with the highest precision in an adequate working range of several thousand cubic millimeters.

Eyeblinks are the brief closures of the lid. They are accompanied by a cocontraction of the eye muscles that temporarily pulls the whole eyeball back into its socket. When blinks occur together with execution of saccadic gaze shifts, they interfere with the saccadic premotor circuit, causing these within-blink saccades to be slower than normal and also time-locked to blinks. To analyze the trajectory of within-blink saccades, subtraction of the entangled blink-related eye movement is required. Here we propose a combination of principal component analysis (PCA) and a regression model to subtract the blink-related component of the eye movement based on the respective blink metrics. We used electrooculography (EOG) to measure eye and lid movements of 12 participants who performed saccades with and without blinks. We found that within-blink saccades are slower than without-blink saccades and are tightly coupled in time to blink onset. Surprisingly, in some participants we observed large dynamic overshoots of up to 15° for saccades of only 5° amplitude. The finding of dynamic overshoots was independently confirmed by dynamic MRI for two of the participants and challenges the current view that within-blink saccades are programmed as slow, but straight, saccades. We hypothesize that the dynamic overshoots could be attributed to inhibition of omnipause neurons during blinks, the simultaneous cocontraction of extraocular muscles, or a combination of both.

Blinks occur frequently in normal life and have increasingly been linked to perceptual and cognitive effects. However, the oculomechanics of blink-related eye movements are much less researched than other types of eye movements. While it has been observed that the eye is being pulled back into its socket during a blink, possibly due to co-contraction of extraocular muscles, this elusive eye motion has not been studied in detail due to the technical difficulties that go along with a closed eyelid. Here we use dynamic magnetic resonance imaging (MRI) to obtain videos of this motion and analyse the kinematics with the recently developed MREyeTrack algorithm. We show that the eye is not only retracted but also lifted up during a blink. For some participants we observed eyeball lifting by up to 3 mm, far exceeding the amount of translation believed to occur during natural eye movements. Slow blinks can be accompanied by large tonic rotations of up to 15°. Furthermore, we collected evidence that the co-contraction of extraocular muscles leads to a slight compression of the eyeball. These findings demonstrate the surprising complexity of ocular motility and offer new opportunities to study orbital mechanics in health and disease.

Zusammenfassung Mit der Entwicklung eines neuen Sensorsystems nach dem chromatisch konfokalen Prinzip erweitern sich die Anwendungsmöglichkeiten für Nano-Koordinatenmessmaschinen [8]. Unter Verwendung der im Institut für Prozessmess- und Sensortechnik (IPMS) der Technischen Universität Ilmenau entwickelten Nanopositionier- und Nanomessmaschinen (NPMM) stehen ausgedehnte und präzise adressier- und positionierbare Mess- und Arbeitsvolumina zur Verfügung [9]. Beschrieben wird die Integration des neuen Sensors in die NPMM, sowie die Erweiterung des Systems um einen Lithografielaser für maskenloses direktes Laserschreiben (engl. Direct-Laser-Writing (DLW)) [16]. Die messtechnischen Eigenschaften des Sensors werden vorgestellt und seine Anwendungsmöglichkeit in lithografischen Strukturierungsprozessen erweitert. Der Sensor wird genutzt, um den Bearbeitungslaser im Bereich seiner Tiefenschärfe konsequent auf die Probenoberfläche zu fokussieren. Dadurch werden Strukturbreiten minimiert [17].

Our eyes are constantly in motion and the various kinds of eye movements are closely linked to many aspects of human cognitive processing. Measuring all possible eye movements unobtrusively is not achievable with current methods. Video-based eye-trackers only measure rotational but not translational motion of the eye, require a calibration process relying on the participant’s self-report of accurate fixation, and do not work if vision of the eyeball is blocked. Scleral search coils attach physical weight on the eyeball and also do not measure translation. Here, we describe a novel and fully automated method to use real-time magnetic resonance imaging (MRI) for eye tracking. We achieved a temporal resolution sufficient to measure eye rotations and translations as short as those that occur within a blink and behind a closed eyelid. To demonstrate this method, we measured the full extent of the blink-related eye movement for two individuals, suggesting that the eye approaches a holding position during lid closure and can move by as much as 35° in rotation and 2 mm in translation. We also investigated the coordination of gaze shifts with blinks. We found that the gaze shift is tightly coupled in time to the translational blink movement and that blinks can induce significant temporal shifts of the gaze trajectory between left and right eye. Our MR-based Eye Tracking (MREyeTrack) method allows measurement of eye movements in terms of both translation and rotation and enables new opportunities for studying ocular motility and its disorders.

Nanofabrication in macroscopic working areas addresses the manipulation with nanometer precision in large scale working areas of several hundred millimeters. In order to reduce the fabrication time of large objects, high dynamic position tracking is required. The position and orientation of the nanopositioning and nanomeasuring machine have to be controlled permanently to compensate external disturbances like ground motion, sound waves, et cetera. Many applications have strict demands on following the track, e.g. to reduce the line roughness. High performant data and signal processing and efficient control algorithms are required to overcome these challenges. This work presents the nanopositioning and measuring machine as well as the utilized control system. Several scanning and fabrication experiments have been carried out in order to demonstrate the performance of the setup.

Metrological stages such as the nano-positioning and nano-measurement machine (NPMM) can position single-digit nanometer accurately on centimeter working volumes. However, their measurement system requires a feedback to the arbitrary shaped specimen by another probe. The differential confocal microscopy (DCM) offers the possibility to have a sensitivity down to that single-digit nanometers but suffers from noise and aberration. Recently the principle of the LockIn filtering could be successfully adapted in DCM and therefore achieved a high SNR. Contrary to the there employed acoustically driven tunable GRIN lens (TAG lens) at the objective, we demonstrate a microelectromechanical system (MEMS), an AFM cantilever, as an ultrafast oscillating pinhole in front of the detector. Its first resonance at 96kHz makes it very competitive regarding acquisition speed, but the low oscillation amplitude lowers contrast. By principle inheriting the possibility to compensate a change in reflectivity, we present another advancement for the evaluation of the resulting differential signal to make it robust against sample induced systematic depth errors, e.g. a tilt-angle. This could be advantageous for DCM with static beam-paths, as well. Potentially, the highest improvement can be achieved in conjunction with the NPMM’s highly accurate measurement interferometers, because the residual error for the depth of a specimen under the influence of varying aberration is kept below 20nm.

Although the field of optical lithography is highly investigated and numerous improvements are made, structure sizes smaller than 20 nm can only be achieved by considerable effort when using conventional technology. To cover the upcoming tasks in future lithography, enormous exertion is put into the development of alternative fabrication technologies in particular for micro- and nanotechnologies that are capable of measuring and patterning at the atomic scale in growing operating areas of several hundred square millimetres. Many new technologies resulted in this process, and are promising to overcome the current limitations1, 2, but most of them are demonstrated in small areas of several square micrometers only, using state-of-the-art piezo stages or the like. At the Technische Universitat Ilmenau, the NanoFabrication Machine 100 (NFM-100) was developed, which serves as an important experimental platform for basic research in the field of scale-spanning AFM tip-based and laser-based nanomeasuring and nanofabrication for simultaneous subnanometre measuring and structuring on surfaces up to O100 mm. This machine can be equipped with several probing systems like AFM, laser focus probes and 3D-micro probes as well as tools for different nanofabrication technologies like tip-based technologies, optical technologies and mechanical two-dimensional technologies in a large working range with subnanometre reproducibility and uncertainty. In this paper, the specifics and advantages of the NFM-100 will be described as well as nanofabrication technologies that are currently worked on e.g. advanced scanning proximal probe lithography based on Fowler-Nordheim-electron-field emission, direct laser writing and UV-nanoimprint lithography.

The active Phase-Field-Crystal (aPFC) model combines elements of the Toner-Tu theory for self-propelled particles and the classical Phase-Field-Crystal (PFC) model that describes the transition between liquid to crystalline phases. In the liquid-crystal coexistence region of the PFC model, crystalline clusters exist in the form of localized states that coexist with the homogeneous background. At sufficiently strong self-propulsion strength (or activity) they start to travel. We employ numerical path continuation and direct time simulations to first investigate the existence regions of different types of localized states for a one-dimensional system. The results are summarized in morphological phase diagrams in the parameter plane spanned by activity and mean concentration. Then we focus on the interaction of traveling localized states studying their collision behavior. As a result we distinguish 'elastic' and 'inelastic' collisions. In the former, localized states recover their properties after a collision while in the latter they may annihilate or form resting or traveling bound states. In passing, we describe oscillating and modulated traveling localized states that have as the steadily traveling localized states no counterpart in the classical PFC model.

To keep up with Moore’s law in future, the critical dimensions of device features must further decrease in size. Thus, the nano-electronics and nano-optics manufacturing is based on the ongoing development of the lithography and encompasses also some unconventional methods. In this context, we use the Nanopositioning and Nanomeasuring Machine (NPMM) to generate features in resist layers by means of Direct Laser Writing (DLW),1 Field Emission Scanning Probe Lithography (FE-SPL)2 and Soft UV-Nanoimprint Lithography (Soft UV-NIL)3 with highest accuracy. The NPMM was collaboratively developed by TU Ilmenau and SIOS Mestechnik GmbH.4 The tool provides a large positioning volume of 25 mm × 25 mm × 5 mm with a positioning resolution of 0.1 nm and a repeatability of less than 0.3 nm over the full range. Previously a single electron transistor (SET) working at room temperature generated by FE-SPL has been demonstrated.5 However, the throughput is limited because of the serial writing scheme making Tennant’s law (At ∼ R5 ) valid.6 Here, At is the areal throughput and R the lithographic resolution. Thus, patterning of the whole NPMM positioning area by FE-SPL is very time consuming. In order to address this problem, different strategies and/or combinations are conceivable. In this work a so-called Mix-and-Match lithography is conducted. A fast generation of structures in the sub-micron range is possible by means of DLW. By this, features such as electrical wires, contact patches for bonding or labels are generated in resist. Subsequently, we use FE-SPL in order to define the actual nano-scaled features for quantum or single electron devices. In combination, DLW and FE-SPL are maskless lithography strategies, hence, offering completely novel opportunities for rapid nanoscale prototyping of largescale resist patterns. An explanation of this technique is given in a previous publication.7 Furthermore, after reactive ion etching, the sample can be used as template for Soft UV-NIL, thus resulting in a high-throughput process chain for future quantum and/or single electron devices.

Imprinting micro- and nanostructures on non-planar surfaces has gained prominence in various fields such as optoelectronics, photonics and biomedical implants. It has been implemented for applications such as optical sensor arrays and optical fibers. Nanoimprint lithography (NIL) is a low cost, high resolution nanofabrication process. In this work, soft UV-NIL process is used in which a flexible stamp is used which makes it ideal for imprinting on curved surfaces such as plano-convex lens. However, the substrate to stamp positioning for successful transfer of patterns is crucial and needs to be addressed. The Nanopositioning and Nanomeasuring machine (NPMM), developed in the Collaborative Research Center (of the German Research Foundation) of TU Ilmenau, provides a unique solution to the challenges of positioning and alignment. Therefore, a UV-LED assisted small scale NIL-setup was designed, developed and integrated into the NPMM and it was further realized for carrying out fabrication of micro- and nanostructures on silicon chips and planoconvex lenses. In addition to scanning electron microscopy (SEM) and atomic force microscopy (AFM) characterization, the structures were further characterized using a focus sensor. The utilized focus sensor is an optical sensor developed at the Institute for Process Measurement and Sensor Technology of TU Ilmenau. It was observed that the imprinted structures were of considerably good fidelity. Thus, a distinctive integrated imprinting process for flat and non-flat surfaces was developed and implemented.

Objectives The delivery of oral health services, diagnostics and treatment underwent significant changes in the 20th century thanks to achievements by pioneers in dentistry. The Golden Age of Dentistry in Vienna, Austria, was marked by renowned dentists like Bernhard Gottlieb in the 1930s. Data records from the outpatient department of this period have been found and served as a source from which to draw comparisons between those days and the present. To date, data supporting an overall perception of advances in dentistry during the last century in tooth preservation and patients' demands have been lacking. The aim of this study was to evaluate changes in treatments and patient characteristics between the interwar period and the present and to assess how treatments for dental emergencies developed. Methods Patients' records were extracted from books handwritten from January to May 1933 and compared with electronically generated data from the same period in 2013. In total, patient data from 10 111 individuals (3878 in 1933 and 6233 in 2013) were analysed. Comparisons were undertaken for gender, age, place of residence, diagnosis and therapy. Results Various statistically significant demographic and treatment differences were found between 1933 and 2013. Patients' mean ages in 2013 and 1933 were 42 and 31 years, respectively. In 2013, there were significantly more women than in 1933 (3378 vs 1936), with 54% women in 2013 and 50% women in 1933. In 2013, there were significantly fewer tooth extractions as dental emergency treatment than in 1933 (2% vs 34%). Conclusions Treatment in the outpatient department is much more conservative in the 21st century. The characteristics of patients visiting the outpatient department have changed over the generations, and treatment needs should be evaluated accordingly.

Direct Laser Writing techniques like two-photon-polymerization or UV-lithography have become common tools for the micro- and nanofabrication of precise devices like photonic crystals. A decrease in the size of structures of special devices requires a significant better resolution of the laser beam system that can be determined by using different photoinitiators or a second depletion laser for STED-lithography. However, besides the optical limits for the resolution of the laser system due to diffraction effects, the positioning systems for the laser beam or the sample stage lead to further imprecisenesses. To benefit from the high resolution techniques for the structuring process, the need for highly accurate positioning systems has dramatically grown during the last years. A combination of lithographic techniques with a nanopositioning and nanomeasuring machine NMM-1, developed at the TU Ilmenau, enables high precision structuring capability in an extended range. The large positioning volume of 25mm x 25mm x 5mm with a resolution in the sub-nanometer range is a good condition for ultra precision manufacturing with large area 3D-Laser-Lithography. Advantages and disadvantages as well as further developments of the NMM-1 system will be discussed related to current developments in the laser beam and nanopositioning system optimization. Part of the further development is an analysis of the implementability of additional ultra precise rotational systems in the NMM-1 for the unlimited addressability perpendicular to the surface of a hemisphere as key strategy for multiaxial nanopositioning and nanofabrication systems.

5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) is an established pharmacological activator of AMP-activated protein kinase (AMPK). Both, AICAR and AMPK were reported to attenuate inflammation. However, AICAR is known for many AMPK-independent effects, although the mechanisms remain incompletely understood. Here we report a potent suppression of lipopolysaccharide (LPS)-induced inflammatory gene expression by AICAR in primary human macrophages, which occurred independently of its conversion to AMPK-activating 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranosyl monophosphate. Although AICAR did not interfere with activation of cytosolic signalling cascades and nuclear translocation of nuclear factor - κB (NFκB) by LPS, it prevented the recruitment of NFκB and RNA polymerase II to target gene promoters. AICAR also inhibited signal transducer and activator of transcription 3 (STAT3)-dependent induction of interleukin (IL) IL-6 and IL-10 targets, while leaving STAT6 and HIF1α-dependent gene expression in IL-4 and dimethyloxalylgylcine-treated macrophages intact. This points to a transcription factor-specific mode of action. Attenuated gene expression correlated with impaired NFκB and STAT3, but not HIF-binding in electrophoretic mobility shift assays in vitro. Conclusively, AICAR interferes with DNA binding of NFκB and STAT3 to modulate inflammatory responses.

The description and operation of a novel, hybrid spouted vessel/fixed bed filter system for the removal of arsenic from water are presented. The system utilizes zero-valent iron (ZVI) particles circulating in a spouted vessel that continuously generates active colloidal iron corrosion products via the “self-polishing” action between ZVI source particles rolling in the moving bed that forms on the conical bottom of the spouted vessel. This action also serves as a “surface renewal” mechanism for the particles that provides for maximum utilization of the ZVI material. (Results of batch experiments conducted to examine this mechanism are also presented.) The colloidal material produced in this fashion is continuously captured and concentrated in a fixed bed filter located within the spouted vessel reservoir wherein arsenic complexation occurs. It is demonstrated that this system is very effective for arsenic removal in the microgram per liter arsenic concentration (i.e., drinking water treatment) range, reducing 100 μg/L of arsenic to below detectable levels (≪10 μg/L) in less than an hour. A mechanistic analysis of arsenic behavior in the system is presented, identifying the principal components of the population of active colloidal material for arsenic removal that explains the experimental observations and working principles of the system. It is concluded that the apparent kinetic behavior of arsenic in systems where colloidal (i.e., micro/nano) iron corrosion products are dominant can be complex and may not be explained by simple first or zeroth order kinetics.

Portal vein thrombosis complicating acute pancreatitis is more often diagnosed today due to the improved imaging techniques (computed tomography, ultrasound, nmr). Nevertheless the outcome of recent portal vein thrombosis is ill-known. We report on the computed tomographic findings and clinical course of portal vein thrombosis in two patients suffering from acute pancreatitis. Both patients showed spontaneous recanalization of the thrombosis.

Sclerosing peritonitis already has been described as a serious complication of the continuous ambulatory peritoneal dialysis. But different other affections of the peritoneum such as chronic bacterial peritonitis and pancreatitis may result in sclerosing peritonitis, too. The symptom is characterised by thickened small bowel walls and peritoneal membranes as well as peritoneal calcifications which can be shown in computed tomography. We demonstrate two cases of peritoneal ossifications due to peritonitis and pancreatitis.

Tuberculosis remains the most important infectious disease all over the world. We report on the CT findings of lung tuberculosis.Standardised retrospective analysis of the computed tomographic examinations in a total of 100 patients suffering from cultural or histological proven pulmonary tuberculosis.The most common finding in our study group were micronodules and lobular opacities accompanied by enlarged lymph nodes. Cavitation and alteration of the bronchial system (esp. bronchial wall thickening) were found less common. The so-called tree-in bud-appearance which had been estimated by other authors to be rather characteristic for active pulmonary tuberculosis was seen in only 12/100 examinations. It is often found in cases showing severe bronchogenic spreading of the disease.The active pulmonary tuberculosis does not show any pathognomonic sign but the combination of findings as opacities and cavitation and segmental spreaded micronodules make the diagnosis probable. This holds also for the so-called tree-in-bud appearances which may be rather suggestive but is seen only in cases suffering from severe bronchiogenic propagation.

Analysis of sagittal jaw relationship is important in orthodontic diagnosis and treatment planning, and can be investigated by angular or linear parameters. In the present study an analysis was performed using profile cephalograms of 40 children with skeletal Class II malocclusion. A correlation analysis is presented, involving five different methods of expressing sagittal jaw relationships. Whilst some degree of agreement could be noted, it was not possible to suggest a pair of measurements, which in combination, could give a more accurate picture of sagittal jaw relationships.