"Life" shaped by genes that depend on their surrounds

Never was dogmatic reductionism helpful in conceiving the phenomenon of life. The post-genomic era has made it clear that genes alone cannot explain the functioning of whole organisms. Already each cell represents a unique, non-recurring individual. Recent progress in developmental biology has conveyed new perspectives both on the makings of individual organisms (ontogeny), as on evolutionary change (Evo-Devo). The genome (the entirety of all genes) of an animal remains constant from fertilization onwards in each cell. The realization of genes requires molecular environments, in particular pertinent to the cytoplasm of the unfertilized egg. Individuality of an organism therefore is not only determined by its genome, but is shaped through developmental processes (it needs time!). Organisms can only exist through mutual interplays with their respective (molecular and cellular) environments at all levels of organization. Thus, life can be conceived of as endless networks of communication, e.g. as a mutual continuum, connecting all individuals, all species and all generations within their given environments. Evolutionarily, nature does not select fitting genes, but rather viable traits. The presented concepts render it unlikely that it was genes that founded our living world, but rather that distinct environments shaped “genes” (of whatever chemical nature) which proved to be “life-suitable”

Baseline Detection in Historical Documents using Convolutional U-Nets

Baseline detection is still a challenging task for heterogeneous collections of historical documents. We present a novel approach to baseline extraction in such settings, turning out the winning entry to the ICDAR 2017 Competition on Baseline detection (cBAD). It utilizes deep convolutional nets (CNNs) for both, the actual extraction of baselines, as well as for a simple form of layout analysis in a pre-processing step. To the best of our knowledge it is the first CNN-based system for baseline extraction applying a U-net architecture and sliding window detection, profiting from a high local accuracy of the candidate lines extracted. Final baseline post-processing complements our approach, compensating for inaccuracies mainly due to missing context information during sliding window detection. We experimentally evaluate the components of our system individually on the cBAD dataset. Moreover, we investigate how it generalizes to different data by means of the dataset used for the baseline extraction task of the ICDAR 2017 Competition on Layout Analysis for Challenging Medieval Manuscripts (HisDoc). A comparison with the results reported for HisDoc shows that it also outperforms the contestants of the latter.Comment: 6 pages, accepted to DAS 201

Localization Transition in Incommensurate non-Hermitian Systems

A class of one-dimensional lattice models with incommensurate complex potential $V(\theta)=2[\lambda_r cos(\theta)+i \lambda_i sin(\theta)]$ is found to exhibit localization transition at $|\lambda_r|+|\lambda_i|=1$. This transition from extended to localized states manifests in the behavior of the complex eigenspectum. In the extended phase, states with real eigenenergies have finite measure and this measure goes to zero in the localized phase. Furthermore, all extended states exhibit real spectrum provided $|\lambda_r| \ge |\lambda_i|$. Another novel feature of the system is the fact that the imaginary part of the spectrum is sensitive to the boundary conditions {\it only at the onset to localization}

Layer-by-layer biofabrication of coronary covered stents with clickable elastin-like recombinamers

Producción CientíficaCoronary artery disease is the leading cause of death around the world. Endovascular stenting is the preferred treatment option to restore blood flow in the coronary arteries due to the lower perioperative morbidity when compared with more invasive treatment options. However, stent failure is still a major clinical problem, and further technological solutions are required to improve the performance of current stents. Here, we developed coronary stents covered with elastin-like recombinamers (ELRs) by exploiting a layer-by-layer technique combined with catalyst-free click chemistry. The resulting ELR-covered stents were intact after an in vitro simulated implantation procedure by balloon dilatation, which evidenced the elastic performance of the membrane. Additionally, the stents were mechanically stable under high flow conditions, which is in agreement with the covalent and stable nature of the click chemistry crosslinking strategy exploited during the ELR-membrane manufacturing and the successful embedding of the stent. Minimal platelet adhesion was detected after blood exposure in a Chandler loop as shown by scanning electron microscopy. The seeding of human endothelial progenitor cells (EPCs) on the ELR-membranes resulted in a confluent endothelial layer. These results prove the potential of this strategy to develop an advanced generation of coronary stents, with a stable and bioactive elastin-like membrane to exclude the atherosclerotic plaque from the blood stream or to seal coronary perforations and aneurysms, while providing a luminal surface with minimal platelet adhesion and favouring endothelialization.German federal and state governments (project StUpPD_330-18)Ministerio de Economía, Industria y Competitividad (projects PCIN-2015-010 / MAT2016-78903-R)Junta de Castilla y León (project VA317P18

Der biomedizinische Fortschritt: Chancen, Grenzen und Verantwortung

Berge von brennenden Tieren, Bilder vom „Keulen“, Bilder vom geklonten Menschen. Aber auch Euphorisches: nach der Aufklärung des menschlichen Genoms schöpfen Krebs- und AIDS-Kranke, Querschnittsgelähmte und Alzheimer-Patienten neue Hoffnung. Bilder auch von Börsenkursen: vom neuen Markt der Informations- und Biotechnologien hängt unsere ökonomische Zukunft ab. Hinter allem stecken die „Life Sciences“, und oft wird man mit schrägem Blick gefragt, was das für Leute sind, diese Bio- bzw. Lebenswissenschaftler? Die Frage nach den Möglichkeiten und dem wahren Wert des biomedizinischen Fortschritts, nach seiner Kontrolle, nach seiner Verantwortung, nach seiner gesellschaftlichen Bindung wird lauter

Vererbungslehre auf schwankendem Grund: Von der Genetik zur Epigenetik

Die Frage nach der Vererbung von Eigenschaften bei Lebewesen beschäftigt den Menschen seit alters her: das ist Genetik. Auch lange schon beschäftigen sich Biologen mit der Frage, wie sich die vielen Tierarten im Laufe einer langen Stammesgeschichte herausbilden konnten: das ist Evolution. Wie wird Konstantes über Generationen bewahrt und Diverses/Neues eingeführt? Die überragenden Erfolge der Genetik haben uns im Glauben eingelullt, wir hätten diese Prozesse vollständig verstanden. Mit dem Aufkommen der so genannten Epigenetik kommen Grundlagen sowohl der Individual-, wie auch der Stammesentwicklung jedoch wieder ins Schwanken. In diesem Artikel will ich einen kleinen Einblick in das Feld der Epigenetik und ihre gesellschaftliche Relevanz geben

CMOS realization of a 2-layer CNN universal machine chip

Some of the features of the biological retina can be modelled by a cellular neural network (CNN) composed of two dynamically coupled layers of locally connected elementary nonlinear processors. In order to explore the possibilities of these complex spatio-temporal dynamics in image processing, a prototype chip has been developed by implementing this CNN model with analog signal processing blocks. This chip has been designed in a 0.5/spl mu/m CMOS technology. Design challenges, trade-offs and the building blocks of such a high-complexity system (0.5 /spl times/ 10/sup 6/ transistors, most of them operating in analog mode) are presented in this paper.Office of Naval Research (USA) N-00014-00-1-0429Comisión Interministerial de Ciencia y Tecnología TIC-1999-082

Wie Epigenetik unser Weltbild ins Lot bringen kann

Seit der Aufklärung versucht der Mensch, Gott abzuschaffen. Dabei fällt der Zufälligkeit, und damit auch der Ziellosigkeit in der darwinistischen Sicht der Evolution besonderes Gewicht zu. Diese weithin akzeptierten Dogmen stehen diametral gegen jahrtausendealte Vorstellungen, die letztlich in allen Kulturen und Religionen hervorgebracht wurden, daß die Natur eine Schöpfung Gottes sei, in der der Mensch das höchste, Gott-ebenbildliche Wesen sei. Nach Erkenntnissen der klassischen Genetik schienen Gene an die Stelle von Gott getreten zu sein: sie haben absolute Gewalt und beherrschen die belebte Natur. Sie haben je einen eindeutigen Befehl, sind unbeugsam und gerecht, wie Gott im AT. Das Produkt Mensch ist nur einer ihrer zahllosen Spielbälle, existiert vorübergehend, ein Zigeuner in einer verlassenen Ecke des Kosmos (Monod, 1992). Diese neodarwinistische Sicht, die nicht zuletzt zum Niedergang der Kirchen bei uns beiträgt, wird von neuen Erkenntnissen der Entwicklungsbiologie (EvoDevo) infrage gestellt