34 research outputs found

    Gaze Strategy in the Free Flying Zebra Finch (Taeniopygia guttata)

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    Fast moving animals depend on cues derived from the optic flow on their retina. Optic flow from translational locomotion includes information about the three-dimensional composition of the environment, while optic flow experienced during a rotational self motion does not. Thus, a saccadic gaze strategy that segregates rotations from translational movements during locomotion will facilitate extraction of spatial information from the visual input. We analysed whether birds use such a strategy by highspeed video recording zebra finches from two directions during an obstacle avoidance task. Each frame of the recording was examined to derive position and orientation of the beak in three-dimensional space. The data show that in all flights the head orientation was shifted in a saccadic fashion and was kept straight between saccades. Therefore, birds use a gaze strategy that actively stabilizes their gaze during translation to simplify optic flow based navigation. This is the first evidence of birds actively optimizing optic flow during flight

    The spinal cord injury-induced immune deficiency syndrome: results of the SCIentinel study

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    Infections are prevalent after spinal cord injury (SCI), constitute the main cause of death and are a rehabilitation confounder associated with impaired recovery. We hypothesize that SCI causes an acquired lesion-dependent (neurogenic) immune suppression as an underlying mechanism to facilitate infections. The international prospective multicentre cohort study (SCIentinel; protocol registration DRKS00000122; n = 111 patients) was designed to distinguish neurogenic from general trauma-related effects on the immune system. Therefore, SCI patient groups differing by neurological level, i.e. high SCI [thoracic (Th)4 or higher]; low SCI (Th5 or lower) and severity (complete SCI; incomplete SCI), were compared with a reference group of vertebral fracture (VF) patients without SCI. The primary outcome was quantitative monocytic Human Leukocyte Antigen-DR expression (mHLA-DR, synonym MHC II), a validated marker for immune suppression in critically ill patients associated with infection susceptibility. mHLA-DR was assessed from Day 1 to 10 weeks after injury by applying standardized flow cytometry procedures. Secondary outcomes were leucocyte subpopulation counts, serum immunoglobulin levels and clinically defined infections. Linear mixed models with multiple imputation were applied to evaluate group differences of logarithmic-transformed parameters. Mean quantitative mHLA-DR [ln (antibodies/cell)] levels at the primary end point 84 h after injury indicated an immune suppressive state below the normative values of 9.62 in all groups, which further differed in its dimension by neurological level: high SCI [8.95 (98.3% confidence interval, CI: 8.63; 9.26), n = 41], low SCI [9.05 (98.3% CI: 8.73; 9.36), n = 29], and VF without SCI [9.25 (98.3% CI: 8.97; 9.53), n = 41, P = 0.003]. Post hoc analysis accounting for SCI severity revealed the strongest mHLA-DR decrease [8.79 (95% CI: 8.50; 9.08)] in the complete, high SCI group, further demonstrating delayed mHLA-DR recovery [9.08 (95% CI: 8.82; 9.38)] and showing a difference from the VF controls of -0.43 (95% CI: -0.66; -0.20) at 14 days. Complete, high SCI patients also revealed constantly lower serum immunoglobulin G [-0.27 (95% CI: -0.45; -0.10)] and immunoglobulin A [-0.25 (95% CI: -0.49; -0.01)] levels [ln (g/l × 1000)] up to 10 weeks after injury. Low mHLA-DR levels in the range of borderline immunoparalysis (below 9.21) were positively associated with the occurrence and earlier onset of infections, which is consistent with results from studies on stroke or major surgery. Spinal cord injured patients can acquire a secondary, neurogenic immune deficiency syndrome characterized by reduced mHLA-DR expression and relative hypogammaglobulinaemia (combined cellular and humoral immune deficiency). mHLA-DR expression provides a basis to stratify infection-risk in patients with SCI

    Innovate the Innovation : An exploratory study about why digital innovation units are being closed and have to constantly reinvent themselves

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    Background: The advancement of digital technologies and hence the emergence of new opportunities but also changing customer needs force incumbent firms to increase their innovation capacities. Therefore, they must find ways to explore the opportunities of digital innovation, while simultaneously exploiting their core business and ensuring a secured revenue stream. This phenomenon, called organizational ambidexterity, can amongst others be achieved by implementing a digital innovation unit (DIU). DIUs, structurally separated units, especially within Germany, Switzerland and Austria are declared to be successful instruments to increase incumbent’s innovativeness but also to foster an innovation culture and advance the corporate digital transformation while the core organization can focus on core business activities. Research Problem: Despite the prevalent perception of DIUs being successful initiatives to find remedy for incumbents’ conflict of being innovative while simultaneously advancing the core business, in recent years more and more DIUs were closed. This development is particularly interesting as the amount of DIUs is still increasing while on the other hand especially business press claims the end of these units. However, regarding this paradox, academic literature is still rare and has until now primarily focused on the challenges of DIUs but not on their closure. Correspondingly, DIU closure poses a significant research gap. Research Purpose: The study primarily aims to clarify why DIUs are being closed and derive a general theory explaining this phenomenon. Above that, a secondary purpose is to advance knowledge regarding DIUs as a digital innovation instrument and what characterizes a DIU. Finally, we aim to examine whether a closure can be equated with a failure. Research Question: Why are Digital Innovation Units being closed? Research Method: Qualitative, inductive research; Ontology – Relativism; Epistemology – Social Constructionism; Methodology – Grounded Theory; Data Collection – 14 semi- structured in-depth Interviews; Sampling – Purposive, Snowball, Theoretical; Data Analysis – Grounded Analysis Conclusion: Resulting from the findings, a model was developed, that explains five major statements related to DIU closure. On the one hand, we ascertained distinct symptoms that anticipate a closure such as personnel measures and budget cuts. On the other hand, we identified factors that significantly influence the fate of a DIU such as corporate politics or cultural dissonances and identified remnants of closed DIUs. Finally, the immediate reasons why DIUs close can be related to strategic changes within the parent company and to how the DIU is evaluated

    Editing in organisations: reconstructing narrative meaning in Dutch education industries

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    In this paper, we focus on the (internal and external) dynamics of NPM in the daily life of organisations in the educational sector. We concentrate on the ways in which the NPM is shaped, adapted, transformed through a wide variety of organisational editing and 'editors' through a case of organisation transformation at Edu, an educational institution. The contribution aims to fill some blind spots in the current debate on narrative transformation and explores the question which alternative forms and related types of 'editors' can be identified in a process of narrative transformation in the education sector. For this, we focus on Edu, an organisation which offers intermediate vocational education. In the article four alternative types of organisational editors are identified varying from 'fixers', 'rationalisers', 'brokers' to 'shapers'. The main distinction lines for these subtypes seem to be the focus on either the social or cognitive dimension, although these dimensions cannot be entirely separated, and the front or backstage dominance. The research illustrates that organisational editing provides a powerful source for meaning reproduction and modification.narratives; stories; realities; inclusions; organisational editing; organisational transformation; vocational education; social; cognitive dimension; new public management; narrative transformation; organisational editors.

    Nitrogen use (in)efficiency and cereal production in Brazil: current trends and forecasts

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    Here, we provide an analysis to understand the evolution of cereal production and consumption of nitrogen (N) fertilizers in Brazil and to correlate N use efficiency (NUE), greenhouse gas (GHG) emissions and economic and environmental losses. Our results showed that the increased consumption of N fertilizers is associated with a large decrease in NUE in recent years. CO2eq emissions from N fertilization for cereal production were approximately 12 times higher in 2011 compared to 1970. The projected N fertilizer forecasts are 2.09 and 2.37 million ton for 2015 and 2023, respectively. An increase of 0.02% per year in the projected NUE was predicted for the same time period. In a hypothetical scenario, a 2.39% increase in cereal NUE would lead to USD 21 million savings in N fertilizer costs. Thus, increases in NUE rates would lead not only to agronomic and environmental benefits but also to economic improvement

    Konzept zur Beteiligung von Kultureinrichtungen des Landes Brandenburg an der Deutschen Digitalen Bibliothek (DDB)

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    Das Land Brandenburg benötigt eine zentral koordinierte Digitalisierungsinitiative, um einen Beitrag zur Deutschen Digitalen Bibliothek leisten zu können. Die Aufgaben der Koordination, Beratung und Dokumentation sollten von einem Kompetenzzentrum ausgeführt werden. Das Kompetenzzentrum unterstützt alle Einrichtungen bei der Planung von Digitalisierungsstrategien unter Berücksichtigung wirtschaftlicher und technischer Aspekte. Hierzu lokalisiert es bereits vorhandene Ressourcen, und berät bei der Auftragsvergabe zwischen Einrichtungen und externen Dienstleister. Als Digitalisierungsstrategie des Kompetenzzentrums wird eine dreistufige Vorgehensweise vorgeschlagen. Die erste Stufe besteht in der Ermittlung vorhandener Ressourcen und Kompetenzen unter Einbeziehung wirtschaftlicher Gesichtspunkte. Als Ansprechpartner der Kultureinrichtungen vermittelt das Kompetenzzentrum zudem Kooperationen für alle Schritte des Digitalisierungsworkflows. Die zweite Stufe beinhaltet die Initiierung von Digitalisierungsprojekten, d.h. die gezielte Förderung und die Auswahl von für die Digitalisierung wichtigen Kulturgütern. In der dritten Stufe sollen Maßnahmen zum Aufbau von Kompetenz und technischen Infrastrukturen in Brandenburg vorangetrieben werden

    Synthesis of Novel Fluorinated Xanthine Derivatives with High Adenosine A2B Receptor Binding Affinity

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    The G protein-coupled adenosine A2B receptor is suggested to be involved in various pathological processes accompanied by increased levels of adenosine as found in inflammation, hypoxia, and cancer. Therefore, the adenosine A2B receptor is currently in focus as a novel target for cancer therapy as well as for noninvasive molecular imaging via positron emission tomography (PET). Aiming at the development of a radiotracer labeled with the PET radionuclide fluorine-18 for imaging the adenosine A2B receptor in brain tumors, one of the most potent and selective antagonists, the xanthine derivative PSB-603, was selected as a lead compound. As initial biodistribution studies in mice revealed a negligible brain uptake of [3H]PSB-603 (SUV3min: 0.2), structural modifications were performed to optimize the physicochemical properties regarding blood–brain barrier penetration. Two novel fluorinated derivatives bearing a 2-fluoropyridine (5) moiety and a 4-fluoro-piperidine (6) moiety were synthesized, and their affinity towards the four adenosine receptor subtypes was determined in competition binding assays. Both compounds showed high affinity towards the adenosine A2B receptor (Ki (5) = 9.97 ± 0.86 nM; Ki (6) = 12.3 ± 3.6 nM) with moderate selectivity versus the other adenosine receptor subtypes
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