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Journal of imaging 7(10), 209 (2021). doi:10.3390/jimaging7100209, Grating-based phase-contrast and dark-field imaging systems create intensity modulations that are usually modeled with sinusoidal functions to extract transmission, differential-phase shift, and scatter information. Under certain system-related conditions, the modulations become non-sinusoidal and cause artifacts in conventional processing. To account for that, we introduce a piecewise-defined periodic polynomial function that resembles the physical signal formation process, modeling convolutions of binary periodic functions. Additionally, we extend the model with an iterative expectation-maximization algorithm that can account for imprecise grating positions during phase-stepping. We show that this approach can process a higher variety of simulated and experimentally acquired data, avoiding most artifacts., Published by MDPI, Basel

In reluctance and permanent magnet synchronous machines, flux barriers are crucial for magnetic flux guidance. Designed as cutouts, flux barriers reduce the mechanical strength of the rotor construction. To operate these electric drives at higher rotational speed, an alternative flux barrier design is required. Since residual stress influences the magnetic properties of soft magnetic materials, this paper deals with embossing induced residual stress as flux barriers in non-oriented electrical steel with 2.4 wt% silicon and a sheet thickness of 0.35 mm. The investigated flux barriers were fabricated with a cylindrical or spherical punch at two different penetration depths and were compared to a flux barrier fabricated as cutout. A residual stress analysis using Finite Element Analysis helps understanding the mechanism of embossed flux barriers. Additionally, the influence of induced residual stress on the magnetic material behavior is measured using standardized single sheet tests and neutron grating interferometry measurements. This investigation aimed at a better understanding of the flux barrier design by local induction of residual stress.

Einleitung: Trotz großer Fortschritte im Management von Patienten mit intrahepatischem Cholangiokarzinom (IHC) ist die Prognose oftmals schlecht. Dennoch konnte in zahlreichen Studien gezeigt werden, dass ein Langzeitüberleben grundsätzlich möglich ist. Die Identifizierung von Hochrisiko-Patienten oder Patienten mit günstiger Prognose anhand valider prognostischer Marker ist daher von großer Bedeutung. Material und Methoden: Von September 1991 bis März 2010 wurden 195 Patienten, die aufgrund eines IHC in kurativer Absicht operiert wurden, in die Studie eingeschlossen. Neben den histopathologischen Parametern wurden auch klinische Daten und perioperative Details in einer prospektiven Datenbank erfasst und der Einfluss der einzelnen Parameter auf das Patientenüberleben analysiert. Ergebnisse: Das mediane Alter der Patienten am Operationstag lag bei 63 Jahren (24-83). Es zeigte sich, dass etwa zwei Drittel eine fortgeschrittenere T-Kategorie aufwiesen (T3: 53,8 %; T4: 11,8 %). Dennoch konnte bei 57,2 % der Patienten eine R0-Resektion erreicht werden. Die postoperative Mortalität des gesamten Kollektivs betrug 5,6 %. Das mediane Über-leben in der Gesamtgruppe lag bei 18,0 Monaten (0,2-221). In der univariaten Überlebensanalyse zeigte sich ein signifikant prognostischer Wert für folgende Parameter: T-Kategorie, LK-Status, Lymphangiosis carcinomatosa (LC), PNS-Infiltration, CA19-9 (Cut-off-Wert 100/U/ml) und R-Status (R0/R1). Weitere Faktoren mit negativem Einfluss auf das Überleben waren: LK-Status (N1 vs. N0: 11 vs. 29 Monate; p, Despite advances in management of patients with intrahepatic cholangiocarcinoma (IHC), the prognosis of these patients often remains poor. Nevertheless, in numerous studies it has been shown that prolonged life expectancy generally is possible. The discrimination between patients with worse and favourable prognosis, respectively, is therefore of great importance. Between September 1991 and March 2012, 195 patients with IHC underwent hepatic resection with curative intend. In addition to the histopathologic parameters, periopera-tive details were recorded in a prospective database. The influence of each parameter on patient survival was controlled and analyzed. The median age of the entire group was 63 years (24-83). About two thirds showed high T-Stage (T3: 53,8% and T4: 11,8%). Nevertheless, R0-resection could be obtained in 57,2 percent. Postoperative mortality was 5,6 percent. Median survival was 18,0 month (0,2-221). Univariate analysis showed significant prognostic results for some parameters: T-Stage (T), Lymphnode-Stage (N), Lymphangiosis carcinomatosa (LC), Perineural Infiltration (PNS-Infiltration), postoperative complications, CA19-9, and R-Status (R0/R1). Further parameters which negatively influenced survival were: positive lymph node status (11 vs. 29 months; p