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The time-optimal path following (OPF) problem is to find a time evolution along a prescribed path in task space with shortest time duration. Numerical solution algorithms rely on an algorithm-specific (usually equidistant) sampling of the path parameter. This does not account for the dynamics in joint space, that is, the actual motion of the robot, however. Moreover, a well-known problem is that large joint velocities are obtained when approaching singularities, even for slow task space motions. This can be avoided by a sampling in joint space, where the path parameter is replaced by the arc length. Such discretization in task space leads to an adaptive refinement according to the nonlinear forward kinematics and guarantees bounded joint velocities. The adaptive refinement is also beneficial for the numerical solution of the problem. It is shown that this yields trajectories with improved continuity compared to an equidistant sampling. The OPF is reformulated as a second-order cone programming and solved numerically. The approach is demonstrated for a 6-DOF industrial robot following various paths in task space.

Zusammenfassung Hintergrund Die Strahlentherapie ist ein integraler Bestandteil in den meisten modernen multimodalen Tumortherapiekonzepten sowohl in kurativen als auch in palliativen Therapiesituationen. Dies gilt auch für viele Tumorentitäten im allgemein- und viszeralchirurgischen Bereich. Dabei kann es zu neuen Herausforderungen im Rahmen des klinischen Alltags und der interdisziplinären Tumorkonferenzen kommen. Ziel Praxisrelevanter Überblick, basierend auf selektiven Referenzen der aktuellen medizinisch-wissenschaftlichen Literatur und gewonnenen klinischen Alltagserfahrungen, für den onkologisch tätigen Chirurgen über strahlentherapeutische Therapieoptionen bei viszeralmedizinischen Tumoren mit dem Fokus auf die viszeralonkologischen Tumoren wie Rektumkarzinom, Ösophaguskarzinom, Analkarzinom und Lebermetastasen Methode Es wird eine narrative Übersicht präsentiert. Ergebnisse (selektive Eckpunkte) In ausgewählten Fällen ist es beispielsweise möglich, dass im Rahmen neuer Konzepte beim Rektumkarzinom ein derart gutes Ansprechen erreicht wird, dass unter engmaschiger Kontrolle eine Resektion vermieden werden kann. Beim Ösophaguskarzinom gilt die neoadjuvante Radiochemotherapie mit anschließender Resektion bei allen geeigneten Patienten als Therapieregime der Wahl. Sollte eine Operation nicht infrage kommen, so steht mit der definitiven Radiochemotherapie, insbesondere bei einem Plattenepithelkarzinom, eine gute Alternative zur Verfügung. Beim Analkarzinom bleibt auch im Licht neuster Erkenntnisse die primär definitive Radiochemotherapie als strahlentherapeutische Therapie der Wahl. Lebertumoren können mithilfe der stereotaktischen Strahlentherapie lokal abladiert werden. Mit der Leberstereotaxie ist ein hoch wirksames Mittel mit geringer Nebenwirkungsrate verfügbar. Schlussfolgerung Auch vor dem Hintergrund der jüngsten Studien bleibt die enge Zusammenarbeit der Disziplinen im Rahmen der Tumortherapie essenziell zur bestmöglichen Therapie der betroffenen Patienten.

Aims To determine the risk of subsequent adverse clinical outcomes in anticoagulated patients with atrial fibrillation (AF) who experienced a new bleeding event. Methods and results Anticoagulated AF patients were followed in two prospective cohort studies. Information on incident bleeding was systematically collected during yearly follow-up visits and events were adjudicated as major bleeding or clinically relevant non-major bleeding (CRNMB) according to the International Society on Thrombosis and Haemostasis guidelines. The primary outcome was a composite of stroke, myocardial infarction (MI), or all-cause death. Time-updated multivariable Cox proportional-hazards models were used to compare outcomes in patients with and without incident bleeding. Median follow-up was 4.08 years [interquartile range (IQR): 2.93–5.98]. Of the 3277 patients included (mean age 72 years, 28.5% women), 646 (19.7%) developed a new bleeding, 297 (9.1%) a major bleeding and 418 (12.8%) a CRNMB. The incidence of the primary outcome was 7.08 and 4.04 per 100 patient-years in patients with and without any bleeding [adjusted hazard ratio (aHR): 1.36, 95% confidence interval (CI): 1.16–1.61; P < 0.001; median time between a new bleeding and a primary outcome 306 days (IQR: 23–832)]. Recurrent bleeding occurred in 126 patients [incidence, 8.65 per 100 patient-years (95% CI: 7.26–10.30)]. In patients with and without a major bleeding, the incidence of the primary outcome was 11.00 and 4.06 per 100 patient-years [aHR: 2.04, 95% CI: 1.69–2.46; P < 0.001; median time to a primary outcome 142 days (IQR: 9–518)], and 59 had recurrent bleeding [11.61 per 100 patient-years (95% CI: 8.99–14.98)]. The incidence of the primary outcome was 5.29 and 4.55 in patients with and without CRNMB [aHR: 0.94, 95% CI: 0.76–1.15; P = 0.53; median time to a composite outcome 505 days (IQR: 153–1079)], and 87 had recurrent bleeding [8.43 per 100 patient-years (95% CI: 6.83–10.40)]. Patients who had their oral anticoagulation (OAC) discontinued after their first bleeding episode had a higher incidence of the primary composite than those who continued OAC (63/89 vs. 159/557 patients; aHR: 4.46, 95% CI: 3.16–6.31; P < 0.001). Conclusion In anticoagulated AF patients, major bleeding but not CRNMB was associated with a high risk of adverse outcomes, part of which may be explained by OAC discontinuation. Most events occurred late after the bleeding episode, emphasizing the importance of long-term follow-up in these patients.

Intestinal amoebiasis in a 35-year-old German patient with a 3 weeks travel history in Indonesia was initially misidentified as non-steroidal anti-inflammatory-drug associated colitis in colonoscopy and histopathological analysis. Furthermore, initial stool examination by microscopy and Entamoeba faecal antigen ELISA did not reveal any protozoan infection. When cessation of non-steroidal anti-inflammatory drug (NSAID) use and mesalazine treatment did not lead to clinical improvement, the patient presented to a specialist for tropical diseases. An intensive reinvestigation including a workup of formalin-fixed, paraffin-embedded colonic biopsies by molecular analysis with real-time PCR and fluorescence in situ hybridization (FISH) proofed the diagnosis of Entamoeba histolytica colitis. Molecular methods including real-time PCR and FISH for the diagnosis of amoebiasis from histopathological samples are rarely used for the diagnosis of E. histolytica infections. Bloody diarrhoea vanished after the onset of metronidazole treatment. In conclusion, the here-presented case demonstrates how modern molecular diagnostics may help to diagnose E. histolytica-associated colitis, even from difficult specimens like paraffin-embedded, formalin-fixed tissue.

The examination of undetermined material of Moroccan bees of the tribe Osmiini (Megachilidae) and several excursions to Morocco in the past fifteen years revealed the existence of numerous undescribed osmiine bee species, indicating that the Moroccan osmiine bee diversity is distinctly higher than the 148 species listed in a recent compilation. In the present publication, 14 of these new species are described: Hoplitis (Alcidamea) herrmanni spec. nov., Hoplitis (Anthocopa) clypeoincisa spec. nov., Hoplitis (Anthocopa) convolvuli spec. nov., Hoplitis (Anthocopa) prazi spec. nov., Hoplitis (Anthocopa) sedivyi spec. nov., Hoplitis (Anthocopa) sternocarinata spec. nov., Hoplitis (Anthocopa) widmeri spec. nov., Hoplitis (Hoplitis) maussi spec. nov., Hoplitis (Hoplitis) prosii spec. nov., Hoplitis (Hoplitis) weibeli spec. nov., Hoplitis (Tkalcua) sidiifnii spec. nov., Osmia (Nasutosmia) longipalpa spec. nov., Protosmia (Nanosmia) curviseta spec. nov. and Protosmia (Nanosmia) magna spec. nov.. Apart from H. prazi, which has a wide distribution ranging from Morocco eastwards to the Levant, and H. clypeoincisa, which has been found in northeastern Morocco and is expected to occur also in neighbouring Algeria, all other new species have been recorded only in southern Morocco and are possibly Moroccan endemics.