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Electrocardiograms (ECG) record the heart activity and are the most common and reliable method to detect cardiac arrhythmias, such as atrial fibrillation (AFib). Lately, many commercially available devices such as smartwatches are offering ECG monitoring. Therefore, there is increasing demand for designing deep learning models with the perspective to be physically implemented on these small portable devices with limited energy supply. In this paper, a workflow for the design of small, energy-efficient recurrent convolutional neural network (RCNN) architecture for AFib detection is proposed. However, the approach can be well generalized to every type of long time series. In contrast to previous studies, that demand thousands of additional network neurons and millions of extra model parameters, the logical steps for the generation of a CNN with only 114 trainable parameters are described. The model consists of a small segmented CNN in combination with an optimal energy classifier. The architectural decisions are made by using the energy consumption as a metric in an equally important way as the accuracy. The optimization steps are focused on the software which can be embedded afterwards on a physical chip. Finally, a comparison with some previous relevant studies suggests that the widely used huge CNNs for similar tasks are mostly redundant and unessentially computationally expensive.
Thermoanaerobacter kivui is an acetogenic model organism that reduces CO2 with electrons derived from H2 or CO, or from organic substrates in the Wood–Ljugdahl pathway (WLP). For the calculation of ATP yields, it is necessary to know the electron carriers involved in coupling of the oxidative and reductive parts of metabolism. Analyses of key catabolic oxidoreductases in cell-free extract (CFE) or with purified enzymes revealed the physiological electron carriers involved. The glyceraldehyde-3-phosphate dehydrogenase (GA3P-DH) assayed in CFE was NAD+-specific, NADP+ was used with less than 4% and ferredoxin (Fd) was not used. The methylene-THF dehydrogenase was NADP+-specific, NAD+ or Fd were not used. A Nfn-type transhydrogenase that catalyzes reduced Fd-dependent reduction of NADP+ with NADH as electron donor was also identified in CFE. The electron carriers used by the potential electron-bifurcating hydrogenase (HydABC) could not be unambiguously determined in CFE for technical reasons. Therefore, the enzyme was produced homologously in T. kivui and purified by affinity chromatography. HydABC contained 33.9 ± 4.5 mol Fe/mol of protein and FMN; it reduced NADP+ but not NAD+. The methylene-THF reductase (MetFV) was also produced homologously in T. kivui and purified by affinity chromatography. MetFV contained 7.2 ± 0.4 mol Fe/mol of protein and FMN; the complex did neither use NADPH nor NADH as reductant but only reduced Fd. In sum, these analysis allowed us to propose a scheme for entire electron flow and bioenergetics in T. kivui.
Energy-converting hydrogenases (Ech) are ancient, membrane-bound enzymes that use reduced ferredoxin (Fd) as an electron donor to reduce protons to molecular H2. Experiments with whole cells, membranes and vesicle-fractions suggest that proton reduction is coupled to proton translocation across the cytoplasmatic membrane, but this has never been demonstrated with a purified enzyme. To this end, we produced a His-tagged Ech complex in the thermophilic and anaerobic bacterium Thermoanaerobacter kivui. The enzyme could be purified by affinity chromatography from solubilized membranes with full retention of its eight subunits, as well as full retention of physiological activities, i.e., H2-dependent Fd reduction and Fd2--dependent H2 production. We found the purified enzyme contained 34.2 ± 12.2 mol of iron/mol of protein, in accordance with seven predicted [4Fe-4S]-clusters and one [Ni-Fe]-center. The pH and temperature optima were at 7 to 8 and 66 °C, respectively. Notably, we found that the enzymatic activity was inhibited by N,N′-dicyclohexylcarbodiimide, an agent known to bind ion-translocating glutamates or aspartates buried in the cytoplasmic membrane and thereby inhibiting ion transport. To demonstrate the function of the Ech complex in ion transport, we further established a procedure to incorporate the enzyme complex into liposomes in an active state. We show the enzyme did not require Na+ for activity and did not translocate 22Na+ into the proteoliposomal lumen. In contrast, Ech activity led to the generation of a pH gradient and membrane potential across the proteoliposomal membrane, demonstrating that the Ech complex of T. kivui is a H+-translocating, H+-reducing enzyme.
Currently one of the biggest challenges for society is to combat global warming. A solution to this global threat is the implementation of a CO2-based bioeconomy and a H2-based bioenergy economy. Anaerobic lithotrophic bacteria such as the acetogenic bacteria are key players in the global carbon and H2 cycle and thus prime candidates as driving forces in a H2- and CO2-bioeconomy. Naturally, they convert two molecules of CO2 via the Wood-Ljungdahl pathway (WLP) to one molecule of acetyl-CoA which can be converted to different C2-products (acetate or ethanol) or elongated to C4 (butyrate) or C5-products (caproate). Since there is no net ATP generation from acetate formation, an electron-transport phosphorylation (ETP) module is hooked up to the WLP. ETP provides the cell with additional ATP, but the ATP gain is very low, only a fraction of an ATP per mol of acetate. Since acetogens live at the thermodynamic edge of life, metabolic engineering to obtain high-value products is currently limited by the low energy status of the cells that allows for the production of only a few compounds with rather low specificity. To set the stage for acetogens as production platforms for a wide range of bioproducts from CO2, the energetic barriers have to be overcome. This review summarizes the pathway, the energetics of the pathway and describes ways to overcome energetic barriers in acetogenic C1 conversion.
The pyruvate:ferredoxin oxidoreductase of the thermophilic acetogen, Thermoanaerobacter kivui
(2021)
Pyruvate:ferredoxin oxidoreductase (PFOR) is a key enzyme in bacterial anaerobic metabolism. Since a low-potential ferredoxin (Fd2−) is used as electron carrier, PFOR allows for hydrogen evolution during heterotrophic growth as well as pyruvate synthesis during lithoautotrophic growth. The thermophilic acetogenic model bacterium Thermoanaerobacter kivui can use both modes of lifestyle, but the nature of the PFOR in this organism was previously unestablished. Here, we have isolated PFOR to apparent homogeneity from cells grown on glucose. Peptide mass fingerprinting revealed that it is encoded by pfor1. PFOR uses pyruvate as an electron donor and methylene blue (1.8 U·mg−1) and ferredoxin (Fd; 27.2 U·mg−1) as electron acceptors, and the reaction is dependent on thiamine pyrophosphate, pyruvate, coenzyme A, and Fd. The pH and temperature optima were 7.5 and 66 °C, respectively. We detected 13.6 mol of iron·mol of protein−1, consistent with the presence of three predicted [4Fe–4S] clusters. The ability to provide reduced Fd makes PFOR an interesting auxiliary enzyme for enzyme assays. To simplify and speed up the purification procedure, we established a protocol for homologous protein production in T. kivui. Therefore, pfor1 was cloned and expressed in T. kivui and the encoded protein containing a genetically engineered His-tag was purified in only two steps to apparent homogeneity. The homologously produced PFOR1 had the same properties as the enzyme from T. kivui. The enzyme can be used as auxiliary enzyme in enzymatic assays that require reduced Fd as electron donor, such as electron-bifurcating enzymes, to keep a constant level of reduced Fd.
Treatment predictors are important tools for the management of therapy in patients with chronic hepatitis B and C virus (HBV, HCV) infection. In chronic hepatitis B, several pretreatment parameters have been identified for prediction of virologic response to interferon alfa-based antiviral therapies or treatment with polymerase inhibitors. In interferon alfa and pegylated interferon alfa-treated patients, low baseline HBV DNA concentrations, HBV genotype A (B), and high baseline ALT levels are significantly associated with treatment response. In patients treated with nucleos(t)ide analogues, low baseline HBV DNA but not viral genotype is positively associated with virologic response. During treatment the best predictor of response is HBV DNA kinetics. Early viral suppression is associated with favourable virologic response and reduced risk for subsequent resistance mutations. For the current standard treatment with pegylated interferon alfa and ribavirin in patients with chronic hepatitis C, infection with HCV genotypes 2 and 3, baseline viral load below 400,000–800,000 IU/ml, Asian and Caucasian ethnicity, younger age, low GGT levels, absence of advanced fibrosis/cirrhosis, and absence of steatosis in the liver have been identified as independent pretreatment predictors of a sustained virologic response. After initiation of treatment, initial viral decline with undetectable HCV-RNA at week 4 of therapy (RVR) is the best predictor of sustained virologic response independent of HCV genotype.
Cet article offre une lecture queer de deux nouvelles de Carl Spitteler. La lecture queer ne signifie pas la recherche d'identités homosexuelles dans les textes ; une telle lecture serait en contradiction avec l'histoire de "Conrad der Leutnant" et "Die Mädchenfeinde". Les nouvelles suivent un jeune homme ("Conrad") et deux garçons encore adolescents ("Mädchenfeinde") et montrent comment ils apprennent à s'adapter à un rôle masculin préconçu qui implique la formation de couples hétérosexuels. Cependant, la thèse des deux textes est que les personnages féminins auxquels les personnages masculins s'ouvrent émotionnellement ne séduisent pas leurs partenaires avec des "charmes féminins". Les hommes (militaires) ou les garçons (pensionnat), élevés dans des contextes véritablement homosociaux, développent pour les personnages féminins un désir qui reflète leur socialisation masculine. Les personnages masculins tombent amoureux d'"images masculines", ce qui signifie que les séductrices doivent symboliquement abandonner leur rôle de femme afin de paraître désirables aux yeux de Conrad, Gerold et Hansli.
We synthesized two green-light activatable 5’-caps for oligonucleotides based on the BODIPY and coumarin scaffold. Both bear an alkyne functionality allowing their use in numerous biological applications. They were successfully incorporated in oligonucleotides via solid-phase synthesis. Copper-catalyzed alkyne-azide cycloaddition (CuAAC) using a bisazide photo-tether gave cyclic oligonucleotides that could be relinearized by activation with green light and were shown to exhibit high stability against exonucleases. Chemical ligation as another example for bioconjugation yielded oligonucleotides with an internal strand break site. Irradiation at 530 nm or 565 nm resulted in complete photolysis of both caging groups.
Gene therapy on the move
(2013)
The first gene therapy clinical trials were initiated more than two decades ago. In the early days, gene therapy shared the fate of many experimental medicine approaches and was impeded by the occurrence of severe side effects in a few treated patients. The understanding of the molecular and cellular mechanisms leading to treatment- and/or vector-associated setbacks has resulted in the development of highly sophisticated gene transfer tools with improved safety and therapeutic efficacy. Employing these advanced tools, a series of Phase I/II trials were started in the past few years with excellent clinical results and no side effects reported so far. Moreover, highly efficient gene targeting strategies and site-directed gene editing technologies have been developed and applied clinically. With more than 1900 clinical trials to date, gene therapy has moved from a vision to clinical reality. This review focuses on the application of gene therapy for the correction of inherited diseases, the limitations and drawbacks encountered in some of the early clinical trials and the revival of gene therapy as a powerful treatment option for the correction of monogenic disorders.
The three-dimensional quantification of small-scale processes in the upper troposphere and lower stratosphere is one of the challenges of current atmospheric research and requires the development of new measurement strategies. This work presents the first results from the newly developed Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) obtained during the ESSenCe (ESa Sounder Campaign) and TACTS/ESMVal (TACTS: Transport and composition in the upper troposphere/lowermost stratosphere, ESMVal: Earth System Model Validation) aircraft campaigns. The focus of this work is on the so-called dynamics-mode data characterized by a medium-spectral and a very-high-spatial resolution. The retrieval strategy for the derivation of two- and three-dimensional constituent fields in the upper troposphere and lower stratosphere is presented. Uncertainties of the main retrieval targets (temperature, O3, HNO3, and CFC-12) and their spatial resolution are discussed. During ESSenCe, high-resolution two-dimensional cross-sections have been obtained. Comparisons to collocated remote-sensing and in situ data indicate a good agreement between the data sets. During TACTS/ESMVal, a tomographic flight pattern to sense an intrusion of stratospheric air deep into the troposphere was performed. It was possible to reconstruct this filament at an unprecedented spatial resolution of better than 500 m vertically and 20 × 20 km horizontally.
The three-dimensional quantification of small scale processes in the upper troposphere and lower stratosphere is one of the challenges of current atmospheric research and requires the development of new measurement strategies. This work presents first results from the newly developed Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) obtained during the ESSenCe and TACTS/ESMVal aircraft campaigns. The focus of this work is on the so-called dynamics mode data characterized by a medium spectral and a very high spatial resolution. The retrieval strategy for the derivation of two- and three-dimensional constituent fields in the upper troposphere and lower stratosphere is presented. Uncertainties of the main retrieval targets (temperature, O3, HNO3 and CFC-12) and their spatial resolution are discussed. During ESSenCe, high resolution two-dimensional cross-sections have been obtained. Comparisons to collocated remote-sensing and in-situ data indicate a good agreement between the data sets. During TACTS/ESMVal a tomographic flight pattern to sense an intrusion of stratospheric air deep into the troposphere has been performed. This filament could be reconstructed with an unprecedented spatial resolution of better than 500 m vertically and 20 km × 20 km horizontally.
Die Frankfurter Universitätsklinik hat mit der Eröffnung des interdisziplinären Brustkrebszentrums 1997 im Rhein-Main-Gebiet neue Maßstäbe bei der Behandlung von Brustkrebs gesetzt. Ziel ist es, die diagnostischen und therapeutischen Abläufe in der Brustkrebsbehandlung zu optimieren sowie die ökonomischen und fachlichen Ressourcen besser zu nutzen. Doch eine gute Therapie ist nur ein Werkzeug bei der Bekämpfung der seit Jahren zunehmenden Brustkrebserkrankungen. Nach Kaufmanns Ansicht ist es wichtig, "zweigleisig zu fahren: Früherkennungsmaßnahmen tragen dazu bei, Tumoren früh zu erkennen. Darüber hinaus gilt es, durch mehr Information mehr Körper- und Gesundheitsbewusstsein zu entwickeln. Denn wer gut informiert ist, hat die besseren Chancen."
Editionen separieren Texte von den Kontexten, in denen sie bei ihrem Entstehungsprozess mit der Hand und technischen Schreibwerkzeugen unterschiedlichster Art geschrieben, als Erstdruck publiziert und von den Zeitgenossen ursprünglich rezipiert worden sind. Zugleich generieren sie, je nach ihren editorischen Prämissen, für die späteren Leser durch die von ihnen vollzogene Selektion, die Anordnung nach Textsorten oder die Anwendung anderer Strukturierungsregeln sowie durch die dabei vorgenommene Hierarchisierung, Kommentierung oder auch Nicht-Kommentierung ihrerseits neue Kontexte und konstruieren so ein bestimmtes, die Rezeption lenkendes Profil von Autor und Werk. Das ist, wie bei anderen prominenten Autoren, auch in der Wirkungsgeschichte Walter Benjamins der Fall. Ich möchte diesem Spannungsverhältnis von Dekontextualisierung und Rekontextualisierung im Folgenden am Beispiel der sogenannten 'kleineren' literaturkritischen Arbeiten - schon das Epitheton ist ein Beispiel für den erwähnten Selektions- und Hierarchisierungsprozess - nachgehen, also anhand der 'Kritiken und Rezensionen', die Benjamin seit der zweiten Hälfte der 1920er Jahre in der 'Frankfurter Zeitung', der 'Literarischen Welt' und an anderer Stelle veröffentlicht hat und deren Korpus im Wesentlichen in dem 1972 publizierten dritten Band der 'Gesammelten Schriften' publiziert worden ist. Ich werde mich dabei, in Blick auf den für diesen Beitrag zur Verfügung stehenden Raum, auf die Skizze zentraler Grundprobleme, auf pointierte Thesen und exemplarische Beispiele beschränken – in der Hoffnung, gerade durch solche Verknappung und Pointierung Impulse für eine weiterführende Diskussion der angesprochenen Probleme zu liefern. Einleitend werde ich zunächst einige grundsätzliche Fragen der Benjamin-Edition skizzieren. Im Anschluss daran werde ich die aktuelle Editionslage von Benjamins Arbeiten zur Literaturkritik im Hinblick auf die Leitfrage meines Beitrags, also auf das Spannungsverhältnis von Text(en) und Kontext(en), kritisch analysieren. Schließlich soll anhand einiger ausgewählter Rezensionen exemplarisch gezeigt werden, welche Bedeutung die in der bisherigen Editionspraxis meist ausgeblendeten Kontexte (z.B. Publikations-, Medien-, Wissenschaftskontexte, biografisch-soziale Kontexte, historische und politische Kontexte etc.) für ein Verständnis des Literaturkritikers Benjamin gewinnen können, sofern man ihnen editorisch die gebührende Beachtung schenkt. Dabei werden Umrisse eines neuen und anderen Benjamin-Bildes sichtbar, das sich von dem bisher verbreiteten nicht nur in Nuancen unterscheidet.
In seiner Rezension zur Kritischen Ausgabe der 'Einbahnstraße' schreibt Lorenz Jäger in der 'Frankfurter Allgemeinen Zeitung' vom 11.3.2010: "Zwischen Moskau und Paris liegt der geographische Raum dieses Buches, auch nach Süden hin ist er offen." Tatsächlich spielt der Süden Europas im Leben und Werk Benjamins eine wichtige Rolle. In Italien und Spanien hat er nicht nur längere Phasen seines Lebens verbracht, sondern bekanntlich auch zentrale, seine intellektuelle Entwicklung prägende Zäsuren erlebt. Seine autobiographischen Texte, Reisebilder und die Besprechungen einschlägiger Werke zur Kultur und Landschaft Südeuropas geben davon ein eindrucksvolles Zeugnis. Hinsichtlich der Rezeption der romanischen Literatur im engeren Sinn wird man aber von einer eher schmalen Tür nach Süden sprechen müssen, jedenfalls gemessen an den breiten Toren, die nach Westen in Richtung Frankreich bzw. nach Osten zur russischen Literatur führen. Gewiss, Benjamin kannte die italienischen Klassiker Dante, Petrarca, Boccaccio, Aretino oder Marsilio Ficino, aber sehr tiefe Spuren haben sie in seinem Werk nicht hinterlassen. Etwas anders sieht es bei den großen Autoren des spanischen 'Siglo de Oro' aus. Mit Cervantes als Erzähler, vor allem aber mit dem "Handorakel" von Baltasar Gracián und den Trauerspielen Calderons hat er sich seit den 1920er Jahren wiederholt und intensiv auseinandergesetzt. Aber auch hier fehlt, sieht man von der kurzen Rezension des spanischen Surrealisten Ramón Gómez de la Serna ab, jede nähere Beschäftigung mit bedeutenden Autoren des 19. und 20. Jahrhunderts. Umso auffälliger ist vor diesem Hintergrund das Interesse, das Benjamin dem italienischen Dichter, Philologen, Essayisten und großen Aphoristiker Giacomo Leopardi (1798–1837) entgegengebracht hat. Es findet seinen deutlichsten Niederschlag in der Rezension einer deutschen Übersetzung von Leopardis 'Pensieri', die im Frühjahr 1928 geschrieben wurde und in der 'Literarischen Welt' vom 18.3.1928 erschienen ist. Größere Aufmerksamkeit hat diese Besprechung nicht gefunden. Bekannter ist der sich daran anschließende, zwei Monate später an gleicher Stelle publizierte Disput mit dem Übersetzer Richard Peters, der dem Kritiker Gelegenheit gab, zu grundsätzlichen Fragen der Übersetzungstheorie Stellung zu nehmen (WuN XIII, 144–147). Dagegen wurde die Verbindung zwischen Benjamin und Leopardi bislang in der Forschung von keiner Seite thematisiert.