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Nanopositioning and nanomeasuring machines are 3D coordinate measuring systems with nanometer precision at measurement volumes in the cubic centimeter range whose coordinate base is formed by an interferometer system with a common mirror corner. This mirror corner shows a typical deviation from the orthogonal coordinate base of up to 17 µrad with an uncertainty of 0.07 µrad. After a brief description of nanomeasuring and nanopositioning machines, a transformation model from the skewed coordinate system into the orthogonal coordinate system is determined. Starting from this complete transformation model, the result of model simplifications on the transformation behaviour is analysed and discussed. A GUM-based uncertainty calculation shows that the linearised coordinate transformation does not increase the error and the uncertainty significantly. [ABSTRACT FROM AUTHOR]

Das Messen kleiner Kräfte ist in vielen wissenschaftlichen Bereichen, wie beispielsweise der Physik oder Biologie, erforderlich. Bei Kräften im Bereich von Nanonewton werden typischerweise AFM-Cantilever als Kraftsensoren genutzt. Die Steifigkeit des Cantilevers muss bekannt sein um von der Durchbiegung auf die Kraft zu schließen. Aufgrund von Fertigungsabweichungen kommt es zu einer großen Streuung der Cantileversteifigkeit. Für eine präzise Kraftmessung muss daher jeder einzelne Cantilever kalibriert werden. Das derzeit genauste Kalibrierverfahren basiert darauf die Kraft-Weg-Kennlinie des Cantilevers statisch zu messen und ihren Anstieg zu bestimmen. In diesem Artikel wird ein neuartiger Prüfstand beschrieben welcher nach diesem Prinzip arbeitet. Ein Interferometer misst die Position und eine neuartige, eingelenkige Wägezelle die Kraft des Cantilevers. Die Wägezelle wurde in zwei unabhängigen Experimenten mit übereinstimmendem Ergebnis kalibriert. Abschließend werden die Messergebnisse einer Cantileverkalibrierung präsentiert. The measurement of small forces is required in various fields of science such as biology or physics. A common way to measure forces in the range of nano newton is to utilize AFM-Cantilevers as force sensors. Therefore it is necessarry to know the stiffness of the cantilever. Due to the manufacturing tolerances, each cantilever needs an individual calibration. The state-of-the-art calibration method with the lowest uncertainty is to measure the force-displacement curve whose slope corresponds the stiffness of the cantilever. In this article a novel device is presented that works according to this method. It uses an interferometer to measure the cantilever displacement and a custom load cell to measure the force. The load cell was calibrated in two different ways which lead to similar results. Finally, the measurement of a soft cantilever's stiffness is presentet to demonstrate the capabilities of the device. [ABSTRACT FROM AUTHOR]

Dieses Paper zeigt einen möglichen Aufbau zur in situ Messung der Positionierabweichung von seriell angeordneten Rotationseinheiten mit einem konstanten, gemeinsamen Momentanpol. Mit Hilfe dieses Aufbaus kann die Position des letzten Gliedes der kinematischen Kette in allen drei Raumachsen gemessen werden. Dazu wird der Abstand zu einer hemisphärischen Referenzfläche mit drei mitbewegten kartesisch angeordneten Fabry-Pérot-Interferometern gemessen. Diese Interferometer werden hinlänglich ihrer Eignung zur Messung auf einer gekrümmten Referenzfläche untersucht. Sie zeigen eine periodische Nichtlinearität von ±10nm und eine Positionswiederholbarkeit mit einer Standardabweichung von unter 1.6nm. This paper shows a possible setup for an in setup measurement of the position error of seriell rotational devices with constant instant centre of rotation. With the help of this setup the position of the last element in the kinematic chain can be measured in all three dimensions. Therefore the distance to a hemispherical reference area is measured by three Fabry-Pérot interferometers which are attatched to the last element of the kinematic chain. Those interferometers are analysed concerning their capability, to measure on a curved reference surface. They show a periodic nonlinearity of ±10nm and a standard deviation of the position repeatability of 1.6 nm. [ABSTRACT FROM AUTHOR]

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Für hochgenaue Rundheitsmessungen an Lehrringen müssen systematische Fehlereinflüsse untersucht und erfasst werden. Dies gilt auch für den Rundlauffehler eines Drehtisches, welcher in Messsystemen für die Rundheits- und Zylinderformmessung eingesetzt wird. Für den Ansatz der interferenzoptischen Rundheitsmessung wurde ein kontaktfreies Antastsystem mit zwei integrierten Planspiegelinterferometern am Institut für Prozessmess- und Sensortechnik entwickelt und getestet. Mit einer maximalen Auflösung von bis zu 20 pm ist es möglich, den Rundlauffehler eines Drehtisches mit Luftlagern hochgenau zu bestimmen. Mit einem etablierten Auswerteverfahren in Kombination mit dem neuen interferometrischen Messsystem konnte ein maximaler Rundlauffehler von 537.5 nm bestimmt werden. Die mittlere Reproduzierbarkeit liegt in den durchgeführten Versuchen bei 31.3 nm. Diese Reproduzierbarkeit schließt nicht nur die Reproduzierbarkeit der Rundlaufmessung ein, sondern beinhaltet auch den Rundlauf des Drehtisches. Dass die Rundlaufwerte im Experiment eine solche Reproduzierbarkeit aufweisen, liegt an der rückwirkungsfreien Struktur des Messaufbaus. Weder das Messsystem selbst noch die notwendigen technischen Strukturen zur Lehrringausrichtung sollten den Drehtischrundlauf beeinflussen. It is necessary to know the uncertainty input of the parasite influences for high-accuracy roundness measurements of ring gauges. One of the largest deviations is caused by the concentric run-out error of the utilized rotary table. An optical probe head basing on two integrated laser interferometers has a measurement resolution up to 20 pm. It was developed at the Institute for Process Measurement and Sensor Technology. It is an interesting experiment to use this optical probe head technology for the concentric run-out detection of rotary tables with air bearings. The investigations of this table show a maximal concentric run-out error of 537.5 nm. It was possible to determine this error with a reproducibility of 31.3 nm in maximum. This reproducibility contains not only the reproducibility in the measurement. It contains the concentric run-out error of the rotary table, too. [ABSTRACT FROM AUTHOR]

Accessibility analyses are important for public transit (PT) planning, as they reveal possible deficits in PT services. Since such accessibility analyses are highly time-dependent, the Modifiable Temporal Unit Problem (MTUP) should be considered. In this context, one approach is to calculate accessibility continuously for an entire day and aggregate it appropriately. However, this approach is complex and computationally intensive and is therefore rarely, if ever, applied. Instead, practitioners and researchers rely on simplified methods without considering temporal effects in detail. This paper bridges this gap by developing a simple yet representative method to account for the temporal variability of PT services. For this purpose, we calculate and compare PT accessibility for different time windows and through different aggregation methods for Germany. The results show that PT analyses between 9–11 a.m. were most representative. Alternatively, the time windows between 7–9 a.m. and between 1–3 p.m. adequately reflected accessibility. The median was suitable for aggregating individual time intervals into a representative value for the PT service throughout a day, while the maximum or mean value distorted the results. For practical planning purposes, we therefore recommend using the 9–11 a.m. time window. [ABSTRACT FROM AUTHOR]

This essay explores circular compositions in medieval and early modern art. Delving into the intersection of religious, philosophical, and scientific ideas, the text examines the prevalence of circular depictions in medieval and early modern aesthetics. Utilizing an interdisciplinary approach, the author draws from primary Hermetic and Neoplatonic sources, providing four reasons for this preference. Firstly, this essay explores the scientific understanding of the shape of the universe, planets, and stars. The second reason delves into the psychological, symbolic, and geometric aspects associated with circular compositions, connecting them to Christian cosmological diagrams and symbolism in the visual arts. Furthermore, the essay investigates the conceptualisation of the universe as a mirror reflecting the divine, emphasising the role of beauty in religious art. The essay concludes by examining the visual culture of medieval and early modern periods, tracing the evolution of circular representations from Roman coins and shields to illuminated manuscripts and paintings. The article sheds light on a hitherto underexplored aspect of medieval and early modern cultures, despite its significance in shaping symbolism and organizing iconographic programs within these periods. [ABSTRACT FROM AUTHOR]

(1) Background: The radial forearm flap (RFF) has evolved as the flap of choice for intraoral mucosal reconstructions, providing thin and pliable skin with a safe blood supply. Perforator flaps such as the anterolateral thigh (ALT) flap are increasingly being discussed for the same applications. (2) Methods: Patient history, treatment details, and outcome of 12 patents with moderate to extended defects of the lip and/or nose area that were reconstructed by a folded radial forearm flap were retrospectively evaluated for oncologic and functional outcomes. (3) Results: The mean oncologic and functional follow-up were 21.1 (min. 3.8; max. 83.3) and 31.2 (min. 6; max. 96) months, respectively. All flaps survived without revision. In eight cases, major lip defects were reconstructed by an RFF; in six patients, the palmaris longus tendon was included for lip suspension. The functional results in terms of eating, drinking, and mouth opening were good in five cases, while three patients were graded as fair due to moderate drooling. In seven cases, the major parts of the nose were reconstructed with two good and five fair (nostril constriction in three cases) functional results. (4) Conclusions: The folded RFF remains a unique free flap option for complex three-dimensional lip and nose reconstructions in terms of flexibility, versatility, and robustness. [ABSTRACT FROM AUTHOR]

Transferred naïve CD8 SP + sp CD45.1 SP + sp HA-specific T cells behaved similar to endogenous CD8 SP + sp CD45.2 SP + sp T cells (Fig. (b) CD4, CD8, and FoxP3 and (d) CD8, CD44, and PD-1. e Representative staining for CD8, PD-1, and Ki67 14 and 21 days after tumor induction. f Quantitative analysis at the same time points. The fate of naive tumor-specific T cells (CD8 SP + sp CD45.1 SP + sp HA-specific T cells) adoptively transferred 10 days after tumor induction was also investigated. While effector CD8 SP + sp and CD4 SP + sp Foxp3 SP - sp T cells were found almost exclusively in the tumors of treated mice, CD4 SP + sp Foxp3 SP + sp regulatory T cells (Tregs) were present in the tumors of both mouse groups (Fig. [Extracted from the article]

Gallbladder cancer is associated with a dismal prognosis, and accurate in vivo models will be elemental to improve our understanding of this deadly disease and develop better treatment options. We have generated a transplantation-based murine model for gallbladder cancer that histologically mimics the human disease, including the development of distant metastasis. Murine gallbladder–derived organoids are genetically modified by either retroviral transduction or transfection with CRISPR/Cas9 encoding plasmids, thereby allowing the rapid generation of complex cancer genotypes. We characterize the model in the presence of two of the most frequent oncogenic drivers—Kras and ERBB2—and provide evidence that the tumor histology is highly dependent on the driver oncogene. Further, we demonstrate the utility of the model for the preclinical assessment of novel therapeutic approaches by showing that liposomal Irinotecan (Nal-IRI) is retained in tumor cells and significantly prolongs the survival of gallbladder cancer–bearing mice compared to conventional irinotecan. [ABSTRACT FROM AUTHOR]