Sustained Splits of Attention within versus across Visual Hemifields Produce Distinct Spatial Gain Profiles

Visual attention can be focused concurrently on two stimuli at noncontiguous locations while intermediate stimuli remain ignored. Nevertheless, behavioral performance in multifocal attention tasks falters when attended stimuli fall within one visual hemifield as opposed to when they are distributed across left and right hemifields. This “different-hemifield advantage” has been ascribed to largely independent processing capacities of each cerebral hemisphere in early visual cortices. Here, we investigated how this advantage influences the sustained division of spatial attention. We presented six isoeccentric light-emitting diodes (LEDs) in the lower visual field, each flickering at a different frequency. Participants attended to two LEDs that were spatially separated by an intermediate LED and responded to synchronous events at to-be-attended LEDs. Task-relevant pairs of LEDs were either located in the same hemifield (“within-hemifield” conditions) or separated by the vertical meridian (“across-hemifield” conditions). Flicker-driven brain oscillations, steady-state visual evoked potentials (SSVEPs), indexed the allocation of attention to individual LEDs. Both behavioral performance and SSVEPs indicated enhanced processing of attended LED pairs during “across-hemifield” relative to “within-hemifield” conditions. Moreover, SSVEPs demonstrated effective filtering of intermediate stimuli in “across-hemifield” condition only. Thus, despite identical physical distances between LEDs of attended pairs, the spatial profiles of gain effects differed profoundly between “across-hemifield” and “within-hemifield” conditions. These findings corroborate that early cortical visual processing stages rely on hemisphere-specific processing capacities and highlight their limiting role in the concurrent allocation of visual attention to multiple locations

GDF 15 deficiency induces a progressive Schwann cell loss in vivo and regulates their survival and migration in vitro

Schwann cells are the glial cells of the peripheral nervous system (PNS) with multifunctional roles. Myelinating Schwann cells wrap axons with multilayered myelin sheaths providing electrical insulation and rapid impulse propagation. They also play a key role in the immune response after nerve injury and play an active role during nerve repair by contributing to a surrounding growth environment that allows peripheral nerve axons to regenerate (Rodrigues, Rodrigues et al. 2012). GDF-15, a neurotrophic factor and member of the TGF-β superfamily has been shown to support nerve regeneration (Mensching, Borger et al. 2012; Charalambous, Wang et al. 2013). Schwann cells express GDF-15 and seem to be an important source of GDF 15 in peripheral nerves (Strelau, Strzelczyk et al. 2009). Interestingly, analysis of GDF-15 deficient mice showed a severe and progressive motoneuron loss accompanied by a loss of axons. Moreover, studies in our laboratory showed a hypermyelination in adult mutant mice (Dr. J. Strelau, unpublished data). Together these data suggest that GDF-15 affects Schwann cell. In this study, I first investigated the putative effect of GDF-15 deficiency on Schwann cells and showed for the first time that GDF-15 loss reduces Schwann cell numbers in adult mice. To address the question whether this observation is correlated with an up or down regulation of other important signaling molecules I analyzed several gene expression patterns in adult peripheral nerves and spinal marrow associated with Schwann cells and/or GDF-15. Interestingly, IL-6 expression, a key regulator of the immune response is upregulated in peripheral nerves. However, in vitro studies failed to proof the direct effect of GDF-15 knockdown on IL-6 expression in Schwann cells. For functional studies including GDF-15 dependent proliferation, cell death and migration of Schwann cells I next established a method to produce highly enriched adult Schwann cell cultures, showing that GDF-15 is a survival factor for Schwann cells and that GDF-15 deficient Schwann cells fail to migrate. Both defects were rescued by treatment with recombinant GDF-15. Since GDF-15 specific receptors are not unequivocally identified, I began to investigate the underlying signaling cascades well known to control myelin sheath growth, most notably the putative interaction of GDF-15 with ErbB2 receptor tyrosine kinase, expressed on Schwann cells. Here I showed the activation of the ErbB2 receptor by recombinant GDF-15 in Schwann cells for the first time. Taken together, this suggests that GDF-15 constitutes an important endogenous regulator of Schwann cell functions in the adult

The Evolutionary Dynamics of Infectious Diseases on an Unstable Planet: Insights from Modeling the Stockholm Paradigm

Emerging infectious diseases (EIDs) are, besides a question of food safety and public health, an ecological and evolutionary issue. The recognition of this condition combined with the accumulation of evidence that pathogens are not specialists in their original hosts evidences the need for understanding how the dynamics of interaction between pathogens and hosts occurs. The Stockholm Paradigm (SP) provides the theoretical fundaments to understand the dynamics of diseases and design proactive measures to avoid the emergence and reemergence of infectious diseases. In this review, we revisit the models that evaluate several aspects of the proposed dynamics of the SP, including the complexity nature of the elements that have been associated with this new framework for the evolution of associations. We integrate the results from these studies into a putative dynamic of infectious diseases, discuss subordinate elements of this dynamic, and provide suggestions on how to integrate these findings into the DAMA (Document, Assess, Monitor, Act) protocol

Moving a step forward to promote patient safety and quality of care in Europe

Improving safety and quality of care has always been at the heart of national, European and international policies. The premises of such concern have their roots in the times of the Greek physician Hippocrates of Cos, about the 4th century BC, with the directive primum non nocere (“first do no harm”). [...

Planungsfehler

Planung lässt sich verstehen als die gedankliche Vorwegnahme zukünftiger Handlungen. Geht bei der Planung etwas schief, dann spricht man von einem Planungsfehler. Diese Fehler betreffen entweder die geforderten oder die erreichten Merkmalsausprägungen. In der Theorie wird dieses Thema jedoch kaum behandelt. Dabei gibt es im Grunde unzählige Möglichkeiten, Fehler zu machen

Public discourse and news consumption on online social media: A quantitative, cross-platform analysis of the Italian Referendum

The rising attention to the spreading of fake news and unsubstantiated rumors on online social media and the pivotal role played by confirmation bias led researchers to investigate different aspects of the phenomenon. Experimental evidence showed that confirmatory information gets accepted even if containing deliberately false claims while dissenting information is mainly ignored or might even increase group polarization. It seems reasonable that, to address misinformation problem properly, we have to understand the main determinants behind content consumption and the emergence of narratives on online social media. In this paper we address such a challenge by focusing on the discussion around the Italian Constitutional Referendum by conducting a quantitative, cross-platform analysis on both Facebook public pages and Twitter accounts. We observe the spontaneous emergence of well-separated communities on both platforms. Such a segregation is completely spontaneous, since no categorization of contents was performed a priori. By exploring the dynamics behind the discussion, we find that users tend to restrict their attention to a specific set of Facebook pages/Twitter accounts. Finally, taking advantage of automatic topic extraction and sentiment analysis techniques, we are able to identify the most controversial topics inside and across both platforms. We measure the distance between how a certain topic is presented in the posts/tweets and the related emotional response of users. Our results provide interesting insights for the understanding of the evolution of the core narratives behind different echo chambers and for the early detection of massive viral phenomena around false claims

c-Jun phosphorylation by the human vaccinia-related kinase 1 (VRK1) and its cooperation with the N-terminal kinase of c-Jun (JNK)

The VRK1 kinase is a novel Ser-Thr kinase in the human kinome that diverged from the casein kinase 1 branch. These kinases phosphorylate transcription factors related to stress responses, such as p53. In this report we have studied the phosphorylation of the transcription factor c-Jun in its N-terminal region. The VRK1 protein phosphorylates c-Jun with a Km of 0.4 lM, and is not inhibited by SP600125. VRK1 phosphorylates c-Jun in Ser63 and Ser73 in vitro, the same residues targeted by the N-terminal kinase of c-Jun (JNK). This phosphorylation induces the stabilization and accumulation of the c- Jun protein. VRK1 phosphorylates the endogenous c-Jun in Ser63. VRK1 activates c-Jun dependent transcription, which is dependent on phosphorylation of Ser63 and Ser73. The c-Jun with Ser63Ala and Ser73Ala substitutions is not transcriptionally active when cotransfected with VRK1. VRK1 interacts with c-Jun but not with JNK. The cotransfection of VRK1 and JNK has an additive effect on the transcriptional activation of c-Jun indicating that they can cooperate when both are at suboptimal dose; otherwise, maximum effect by one of them prevents the effect of the other. The VRK1-c-Jun connection represents a component of a new signaling pathway whose upstream elements remain to be identified.Peer reviewe

El lado oscuro del movimiento obrero argentino. Claves para una historia social de los rompehuelgas (Buenos Aires, principios del siglo XX)

En este artículo nos preguntamos por un sector específico del colectivo de trabajadores: aquel que no solo se mantuvo al margen de las luchas del movimiento obrero argentino sino que, además, las enfrentó. La composición de los rompehuelgas no era homogénea y su acción respondía a motivaciones de distinto tipo: ideológicas, políticas, económicas, religiosas, morales, o bien una mezcla de todas ellas. El campo de intervención del llamado “crumiraje” no estuvo exento de presiones por parte de la patronal o de otros actores sociales; en su interior, convivieron formas más o menos autónomas con estructuras más organizadas, especialmente cuando se afectaban las actividades agroexportadoras. A pesar de la importancia que tuvieron las acciones anti huelguísticas, su abordaje por parte de la historiografía ha sido prácticamente nulo hasta el momento. Se propone, entonces, trazar un cuadro de conjunto y proponer una serie de puntos hacia delante

Spies, russians and maximalists in the summer of 1919: The Tragic Week revisited from the diplomatic and journalistic sources

El artículo propone revisitar la Semana Trágica de 1919 en Buenos Aires a partir del análisis sobre las fuentes de la diplomacia y el espionaje extranjeros en el país, problematizando las perspectivas y la bibliografía existente. El relevamiento de materiales poco explorados habilitan la formulación de nuevos interrogantes sobre un tema aparentemente «agotado» respecto del cual, no obstante, recientes trabajos han demostrado que aún quedan diferentes aspectos por profundizarThe aim of this paper is to revisit the Tragic Week of 1919 in Buenos Aires, analyzing new sources that belong from the foreign diplomacy and the espionage. In addition, it examines the mainstreamperspectives and bibliography.The little-explored documents enables new questions on an apparently already-known subject, with respect to which, however, recent works have shown that there are still different aspects to deepenFil: Koppmann, Walter Ludovico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani". Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani"; ArgentinaFil: Asquini, Sabrina Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani". Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani"; Argentin

Bio-Landwirtschaft in Österreich - Einstellungen, Erwartungen und Wissen Jugendlicher und junger Erwachsener

Jugendliche und junge Erwachsene bestimmen durch ihr Verhalten, ihre Erwartungen und Meinungen zur Bio-Land- und Lebensmittelwirtschaft wesentlich die zukünftige Entwicklung des Bio-Sektors mit. Im Rahmen der vorliegenden Studie wurden in Österreich Jugendliche und junge Erwachsene (15-19 Jahre bzw. 20-25 Jahre) gezielt zu Ihren Einstellungen zur Landwirtschaft und Lebensmittelproduktion, zu ihrem Konsum- und Einkaufverhalten, zu den Wünschen und Erwartungen an die Bio-Lebensmittelwirtschaft sowie zu ihrem Bio-Wissen befragt. 47 % der Jugendlichen und jungen Erwachsenen gaben an, dass sie eine sehr hohe und 26 % eine hohe Wertschätzung der Bio-Land- und Lebensmittelwirtschaft entgegen bringen. Eine überdurchschnittlich hohe Bio-Wertschätzung zeigte sich für jene Befragten, welche angaben sich gesund zu ernähren, wenig bzw. kein Fleisch zu essen, weniger gerne Fast-Food zu konsumieren sowie gerne zu kochen. Die „intensiv-Bio-Kunden/innen“ waren überdurchschnittlich gut über „Bio“ informiert, stellten die höchsten Anforderungen an die Bio-Lebensmittelwirtschaft, zeigten aber gleichzeitig auch die höchste Bio-Mehrpreis-Kaufbereitschaft. Einen besonders hohen Stellenwert für die Jugendlichen und jungen Erwachsenen haben folgende Aspekte: 1) Auslauf ins Freie von Tieren, 2) keine Kinderarbeit bei Importwaren, 3) fairer Handel 4) strenge Kontrollen beim Bio-Lebensmittelimport, 5) regionale Herkunft der Lebensmittel, 6) Weidehaltung von Wiederkäuern, 7) Schonung von Boden, Wasser und Umwelt im Bio-Pflanzenbau. 60 % der Jugendlichen und jungen Erwachsenen gaben an zukünftig mehr Bio-Produkte konsumieren zu wollen. 81 % wünschte sich einen weiteren Ausbau der Bio-Land- und Lebensmittelwirtschaft in Österreich