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Ist Nullfokalisierung etwas anderes als (variable) interne und/oder externe Fokalisierung? Der Beitrag argumentiert, dass dies durchaus der Fall ist: Legt man die durch Genette popularisierte Theorie von Fokalisierungstypen zugrunde, so ist Nullfokalisierung nicht auf interne oder externe Fokalisierung zurückführbar. Dasselbe gilt, wenn die Genette'sche Theorie der Fokalisierung durch eine plausiblere Alternativtheorie ersetzt wird. Der Beitrag erläutert und begründet diese Thesen.

Fundamental algorithms such as sorting or hashing are used trillions of times on any given day 1 . As demand for computation grows, it has become critical for these algorithms to be as performant as possible. Whereas remarkable progress has been achieved in the past 2 , making further improvements on the efficiency of these routines has proved challenging for both human scientists and computational approaches. Here we show how artificial intelligence can go beyond the current state of the art by discovering hitherto unknown routines. To realize this, we formulated the task of finding a better sorting routine as a single-player game. We then trained a new deep reinforcement learning agent, AlphaDev, to play this game. AlphaDev discovered small sorting algorithms from scratch that outperformed previously known human benchmarks. These algorithms have been integrated into the LLVM standard C++ sort library 3 . This change to this part of the sort library represents the replacement of a component with an algorithm that has been automatically discovered using reinforcement learning. We also present results in extra domains, showcasing the generality of the approach., (© 2023. The Author(s).)

Non-target screening of suspended particulate matter (SPM), collected from the German rivers Rhine and Saar, was conducted with the goal of identifying organic, permanent cationic contaminants and of estimating their temporal trends over an extended period. Therefore, annual composite samples of SPM, provided by the German Environmental Specimen Bank, were extracted and analyzed with high resolution LC-QToF-MS/MS. To facilitate the identification of substances belonging to the class "permanent cations", prioritization methods were applied utilizing the physicochemical properties of these compounds. These methods include both interactions of the analyte molecules with cation exchange resins and analyzing mass deviations when changing from non-deuterated to deuterated mobile phase solvents during LC-MS analysis. By applying both methods in a combined approach, 123 of the initially detected 2695 features were prioritized, corresponding to a 95% data reduction. This led to the identification of 22 permanent cationic species. The organic dyes Basic Yellow 28 and Fluorescent Brightener 363 as well as two quaternary ammonium compounds (QACs) were detected in environmental samples for the first time to best of or knowledge. The other compounds include additional QACs, as well as quaternary tri-phenylphosphonium compounds (QPC/TPP). In addition to identification, we determined temporal trends of all compounds over a period of 13 years and assessed their ecotoxicological relevance based on estimated concentrations. The two QACs oleyltrimethylammonium and eicosyltrimethylammonium show significant increasing trends in the Rhine SPM and maximum concentrations in the Saar SPM of about 900 and 1400 µg/kg, respectively. In the case of the dyes, constant trends have been observed at the end of the studied period, but also maximum concentrations of 400 µg/kg for Basic Yellow 28 in 2006 and 1000 µg/kg for Fluorescent Brightener 363 in 2015, potentially indicating a strong ecotoxicological risk., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Non-target screening of water samples from the Nidda river basin in central Germany was conducted with the goal to identify previously unknown chemical contaminants and their emission sources. The focus was on organic, water-borne contaminants which were not typical to municipal wastewater. Grab samples of river water from 13 locations on the Nidda and 15 of its tributaries, in sum 112 samples, were analysed with high resolution LC-QToF-MS/MS. To facilitate the identification of substances, features originating from the same compound such as adducts and isotopologues as well as in-source fragments and species with multiple charge states were registered and grouped by a componentization step utilizing both retention times and peak shapes of the features to combine them in a single component. This led to a reduction of the number of features by an average of 1235 per sample (46%). These grouped features were prioritized if these were detected only in specific tributaries or specific river sections, reducing the number of components by an average of 913 per sample (78%). In addition, grouped features were labelled as typically found in municipal wastewater by combining data from 16 wastewater treatment plants located across Germany and Switzerland and comparing this to components detected in the Nidda basin. These were removed, leading to a further reduction of components by an average of 72 per sample (30%) for an average total reduction of 2536 per sample (93%). Finally, nine compounds, with emission sources in three specific tributaries, were identified, including the textile additive Nylostab S-EED®, which was previously not known to be an environmental contaminant, as well as naturally occurring compounds such as highly toxic microcystins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Ltd.)

Background: Currently about 70% of women who suffer from breast cancer undergo breast-conserving therapy (BCT) without removing the entire breast. Thus, this surgical approach is the standard therapy for primary breast cancer. If corrections are necessary, the breast surgeon is faced with irritated skin and higher risks of complications in wound healing. After radiation, an implant-based reconstruction is only recommended in selected cases. Correction of a poor BCT outcome is often only solved with an additional extended operation using autologous reconstruction., Material/methods: In our plastic surgery unit, which focuses on breast reconstruction, we offer a skin-sparing or subcutaneous mastectomy, followed by primary breast reconstruction based on free autologous tissue transfer to correct poor BCT outcomes. Between July 2004 and May 2011 we performed 1068 deep inferior epigastric artery perforator (DIEP) flaps for breast reconstruction, including 64 skin-sparing or subcutaneous mastectomies, followed by primary DIEP breast reconstruction procedures after BCT procedures., Results: In all free flap-based breast reconstruction procedures, we had a total flap loss in 0.8% (9 cases). Within the group of patients after BCT, we performed 41 DIEP flaps and 23 ms-2 TRAM flaps after skin-sparing or subcutaneous mastectomies to reconstruct the breast. Among this group we had of a total flap loss in 1.6% (1 case)., Conclusions: In cases of large tumour sizes and/or difficult tumour locations, the initial oncologic breast surgeon should inform the patients of a possibly poor cosmetic result after BCT and radiation. In our opinion a skin-sparing mastectomy with primary breast reconstruction should be discussed as a valid alternative.