Wie real ist die Realanalyse? Eine Kritik an dem methodischen Ansatz in ,,Entwicklungsphasen und -tendenzen des Kapitalismus in Westdeutschland". (2 Teile, Prokla, IV. Jg, 13, 16, 1974)

In den zwei Jahren seit der Veröffentlichung der BRD-Analyse durch die Prokla 13, 16 unterlag sowohl deren inhaltliches Ergebnis als auch deren Methodik immer grösserer Verbreitung. Dabei wurde mit der Zeit die Zahl der Einwendungen und Einschränkungen tendenziell immer geringer, während andererseits der Grad der festen überzeugung von der Richtigkeit des Vorgehens und der Ergebnisse stetig anstieg. So wurde jener Indikator „Kapitalrentabilität" noch innerhalb des zweiteiligen Artikels stillschweigend mit der „Profitrate" gleichgesetzt, und daraus wurde in der Folgeausgabe der Prokla 17, 18 ein „sogar in historischer Analyse nachweisbarer Fall der Profitrate" (1). Vorsichtig formulierte und verklausulierte-Vorbehalte hinsichtlich der Methode, wie sie noch in Prokla 13 zu finden sind, werden nicht mehr aufgegriffen; es genügt den Autoren seitdem, darauf zu verweisen, daß man zu diesen Fragen bereits „detaillierte methodische überlegungen" angestellt habe (2). Ein solcher Hin weis gibt sodann den Weg frei, um die Indikatoren aus Prokla 13, 16 quasi als vorgefertigtes Rechenprogramm anzuwenden: Fürwahr eine ideale Standardvorlage zur raschen Anfertigung von politökonomischen Analysen für beltebige Länder (3)

Semi-automated computed tomography Volumetry can predict hemihepatectomy specimens’ volumes in patients with hepatic malignancy

Background: One of the major causes of perioperative mortality of patients undergoing major hepatic resections is post-hepatectomy liver failure (PHLF). For preoperative appraisal of the risk of PHLF it is important to accurately predict resectate volume and future liver remnant volume (FLRV). The objective of our study is to prospectively evaluate the accuracy of hemihepatectomy resectate volumes that are determined by computed tomography volumetry (CTV) when compared with intraoperatively measured volumes and weights as gold standard in patients undergoing hemihepatectomy. Methods: Twenty four patients (13 women, 11 men) scheduled for hemihepatectomy due to histologically proven primary or secondary hepatic malignancies were included in our study. CTV was performed using a semi-automated module (S, hereinafter) (syngo.CT Liver Analysis VA30, Siemens Healthcare, Germany). Conversion factors between CT volumes on the one side and intraoperative volumes and weights on the other side were calculated using the method of least squares. Absolute and relative disagreements between CT volumes and intraoperative volumes were determined. Results: A conversion factor of c = 0.906 most precisely predicted intraoperative volumes of exsanguinated hemihepatectomy specimens from CT volumes in all patients with mean absolute and relative disagreements between CT volumes and intraoperative volumes of 57 ml and 6.3%. The use of operation-specific conversion factors yielded even better results. Conclusions: CTV performed with S accurately predicts intraoperative volumes of hemihepatectomy specimens when applying conversion factors which compensate for exsanguination. This allows to precisely estimate the FLRV and thus minimize the risk of PHLF in patients undergoing major hepatic resections

A filter wheel mechanism for the Euclid near-infrared imaging photometer

The Euclid mission is currently being developed within the European Space Agency's Cosmic Vision Program. The five year mission will survey the entire extragalactic sky (~ 20 000 deg2) with the aim of constraining the nature of dark energy and dark matter. The spacecraft's payload consists of two instruments: one imaging instrument, which has both a visible and a near-infrared channel, and one spectroscopic instrument operating in the near-infrared wavelength regime. The two channels of the imaging instrument, the Visible Imaging Channel (VIS) and the Near-Infrared Imaging Photometer Channel (NIP), will focus on the weak lensing science probe. The large survey area and the need to not only image each patch of sky in multiple bands, but also in multiple dithers, requires over 640 000 operations of the NIP channel's filter wheel mechanism. With a 127 mm diameter and a mass of ~ 330 g per element, these brittle infrared filters dictate highly demanding requirements on this single-point-failure mechanism. To accommodate the large filters the wheel must have an outer diameter of ~ 400 mm, which will result in significant loads being applied to the bearing assembly during launch. The centrally driven titanium filter wheel will house the infrared filters in specially designed mounts. Both stepper motor and brushless DC drive systems are being considered and tested for this mechanism. This paper presents the design considerations and details the first prototyping campaign of this mechanism. The design and finite element analysis of the filter mounting concept are also presented

Preparing Herschel's commissioning phase: Ge:Ga detector tuning

The Photodetector Array Camera and Spectrometer (Pacs) instrument aboard the Herschel space observatory contains an integral field spectrometer with two camera channels which consist of 25 linear arrays of 16 stressed Gallium doped Germanium crystals (Ge:Ga) each. The space radiation environment induces changes in the detector performance. Therefore, testing the Ge:Ga detectors under space radiation environment during the commissioning phase (CP) is important for optimization of later detector operation in orbit. The test program for Ge:Ga detector tuning during this phase has been designed according to findings obtained in laboratory experiments: Protons as well as a 137Cs-gamma-source have been used to simulate the space radiation environment and to induce the radiation impacts on the photoconductor arrays. From comparison of the performance of the detectors during CP versus laboratory tests the best strategy for operating the detectors during scientific observations will be derived. This includes annealing, proposals for on-board data reduction algorithms and the best estimated strategy for well-calibrated scientific measurements