Justierbare Getriebeglieder durch integrierte Parallelstruktur

Der Beitrag beschäftigt sich mit der Gestaltung justierbarer Getriebeglieder zur Kompensation von Fertigungstoleranzen. Dafür sind feine Stellbewegungen in allen Raumrichtungen und um alle Raumachsen erforderlich. Die Forderungen lassen die Verwendung eines Hexapoden sinnvoll erscheinen, um das zuvor starre Bauteil einstellbar und dennoch steif zu gestalten. Bekannte Methoden zur Auslegung parallelkinematischer Maschinen werden gezielt vereinfacht und für die Optimierung der Getriebeabmessungen genutzt. Das Vorgehen wird anhand eines seriellen, sphärisch wirkenden Roboterhandgelenks demonstriert. Durch Kombination von Messung und Berechnung entsteht eine einfache Möglichkeit, dessen Gelenkachsen zueinander zu justieren, d. h. sie in einem Punkt zum Schnitt zu bringen

Liver-HERO: hepatorenal syndrome-acute kidney injury (HRS-AKI) treatment with transjugular intrahepatic portosystemic shunt in patients with cirrhosis—a randomized controlled trial

Abstract Background Patients with cirrhosis and ascites (and portal hypertension) are at risk of developing acute kidney injury (AKI). Although many etiologies exist, hepatorenal AKI (HRS-AKI) remains a frequent and difficult-to-treat cause, with a very high mortality when left untreated. The standard of care is the use of terlipressin and albumin. This can lead to reversal of AKI, which is associated to survival. Nevertheless, only approximately half of the patients achieve this reversal and even after reversal patients remains at risk for new episodes of HRS-AKI. TIPS is accepted for use in patients with variceal bleeding and refractory ascites, which leads to a reduction in portal pressure. Although preliminary data suggest it may be useful in HRS-AKI, its use in this setting is controversial and caution is recommended given the fact that HRS-AKI is associated to cardiac alterations and acute-on-chronic liver failure (ACLF) which represent relative contraindications for transjugular intrahepatic portosystemic shunt (TIPS). In the last decades, with the new definition of renal failure in patients with cirrhosis, patients are identified at an earlier stage. These patients are less sick and therefore more likely to not have contraindications for TIPS. We hypothesize that TIPS could be superior to the standard of care in patients with HRS-AKI. Methods This study is a prospective, multicenter, open, 1:1-randomized, controlled parallel-group trial. The main end-point is to compare the 12-month liver transplant-free survival in patients assigned to TIPS compared to the standard of care (terlipressin and albumin). Secondary end-point include reversal of HRS-AKI, health-related Quality of Life (HrQoL), and incidence of further decompensation among others. Once patients are diagnosed with HRS-AKI, they will be randomized to TIPS or Standard of Care (SOC). TIPS should be placed within 72 h. Until TIPS placement, TIPS patients will be treated with terlipressin and albumin. Once TIPS is placed, terlipressin and albumin should be weaned off according to the attending physician. Discussion If the trial were to show a survival advantage for patients who undergo TIPS placement, this could be incorporated in routine clinical practice in the management of patients with HRS-AKI. Trial registration Clinicaltrials.gov NCT05346393 . Released to the public on 01 April 2022

A New Dimension in Cyclic Coinage Metal Pyrazolates: Decoration with a Second Ring of Coinage Metals by Inter-ring Metallophilic Interactions

When pyrazolate ligands with thioether chelate arms are used in cyclic coinage metal pyrazolates [Au(μ-pz)]n, the inner gold ring can be framed with an outer silver ring to give novel heterometallic double-crowned complexes [AuAg(μ-Lx)(BF4)]4. They feature short intramolecular in-plane Ag–Au interactions, are stable as octanuclear species in solution, and show promising luminescence properties