Journalistische Qualität

Die Arbeit behandelt das Thema journalistische Qualität und setzt sich zunächst mit dem Stand der Forschung zu diesem Gegenstand auseinander. Seit Mitte der achtziger Jahre ist, parallel zum etwas früher einsetzenden Ethikdiskurs, eine breite Debatte feststellbar, die sich mit Kriterien und Messinstrumenten für journalistische Qualität auseinandersetzt. Die Ansätze entstammen den unterschiedlichen Positionen innerhalb der Kommunikationswissenschaft und reichen demnach von normativen Forderungen an den Journalismus über systemtheoretische Perspektiven bis hin zu rein publikumsorientierten Zugangsweisen. Zahlreiche Modelle, unter denen das Magische Vieleck Ruß-Mohls den meistverbreiteten Ansatz darstellt, bilden die Grundlage einer wissenschaftlichen Annäherung an journalistische Qualität. Zentraler Bestandteil der Arbeit ist eine Inhaltsanalyse des Nachrichten-magazins „Profil“, die nicht nur die Aufgabe hat, Aussagen über die Qualität dieses Printmediums zu liefern, sondern deren Gestaltung und Durchführung Aufschlüsse über Möglichkeiten und Grenzen der Inhaltsanalyse bei der Messbarmachung journalistischer Qualität im Allgemeinen bringen soll. Dabei erweist sich die Inhaltsanalyse als praktikables Instrument für eine auf konkreten Beiträgen bzw. Texten beruhende Operationalisierung journalistischer Qualität. Voraussetzung hierfür ist allerdings eine qualitative Zugangsweise, die sich sogar hermeneutischer Elemente bedient und damit in Widerspruch zu der Ansicht von Vertretern der quantitativen Inhaltsanalyse steht, wonach sich diese auf die Analyse des manifesten Teils einer Nachricht zu beschränken habe. Ungeachtet solcher Differenzen ist jedoch festzustellen, dass die Inhaltsanalyse als einziges Instrument zur Feststellung journalistischer Qualität nicht ausreicht, da mit ihr wesentliche Aspekte, vorrangig jene mit Blick auf Akteure und Medienunternehmen, außer Acht bleiben müssen. Für das Nachrichtenmagazin „Profil“ stellt die Studie mittels einer Stichprobe aus dem Jahr 2008 fest, dass qualitativ gute journalistische Arbeit geleistet wird und „Profil“ – soweit dies mit der hier angewandten Methode nachweisbar ist – als Qualitätsmedium bezeichnet werden kann. Auch eine Längsschnittuntersuchung der Jahre 1999 bis 2008 zeigt, dass „Profil“ über den ganzen Zeitraum auf hohem Qualitätsniveau arbeitet, wobei die wenigen nachgewiesenen Fälle von Verstößen gegen journalistische Qualität größtenteils aus der Zeit bis einschließlich 2004 stammen. Es ist also eine ‚Verbesserung auf hohem Niveau’ zu erkennen

GLAVITU:A Hybrid CNN-Transformer for Multi-Regional Glacier Mapping from Multi-Source Data

Glacier mapping is essential for studying and monitoring the impacts of climate change. However, several challenges such as debris-covered ice and highly variable landscapes across glacierized regions worldwide complicate large-scale glacier mapping in a fully-automated manner. This work presents a novel hybrid CNN-transformer model (GlaViTU) for multi-regional glacier mapping. Our model outperforms three baseline models - SETR-B/16, ResU-Net and TransU-Net - achieving a higher mean IoU of 0.875 and demonstrates better generalization ability. The proposed model is also parameter-efficient, with approximately 10 and 3 times fewer parameters than SETR-B/16 and ResU-Net, respectively. Our results provide a solid foundation for future studies on the application of deep learning methods for global glacier mapping. To facilitate reproducibility, we have shared our data set, codebase and pretrained models on GitHub at https://github.com/konstantin-a-maslov/GlaViTU-IGARSS2023.</p

Circum-Arctic changes in the flow of glaciers and ice caps from satellite SAR data between the 1990s and 2017

We computed circum-Arctic surface velocitymaps of glaciers and ice caps over the Canadian Arctic, Svalbard and the Russian Arctic for at least two times between the 1990s and 2017 using satellite SAR data. Our analyses are mainly performed with offset-tracking of ALOS-1 PALSAR-1 (2007–2011) and Sentinel-1 (2015–2017) data. In certain cases JERS-1 SAR (1994–1998), TerraSAR-X (2008–2012), Radarsat-2 (2009–2016) and ALOS-2 PALSAR-2 (2015–2016) data were used to fill-in spatial or temporal gaps. Validation of the latest Sentinel-1 results was accomplished by means of SAR data at higher spatial resolution (Radarsat-2Wide Ultra Fine) and ground-basedmeasurements. In general, we observe a deceleration of flow velocities for the major tidewater glaciers in the Canadian Arctic and an increase in frontal velocity along with a retreat of frontal positions over Svalbard and the Russian Arctic. However, all regions have strong accelerations for selected glaciers. The latter developments can be well traced based on the very high temporal sampling of Sentinel-1 acquisitions since 2015, revealing new insights in glacier dynamics. For example, surges on Spitsbergen (e.g., Negribreen, Nathorsbreen, Penckbreen and Strongbreen) have a different characteristic and timing than those over Eastern Austfonna and Edgeoya (e.g., Basin 3, Basin 2 and Stonebreen). Events similar to those ongoing on Eastern Austofonna were also observed over the Vavilov Ice Cap on Severnaya Zemlya and possibly Simony Glacier on Franz-Josef Land. Collectively, there seems to be a recently increasing number of glaciers with frontal destabilization over Eastern Svalbard and the Russian Arctic compared to the 1990s

Simulating the roles of crevasse routing of surface water and basal friction on the surge evolution of Basin 3, Austfonna ice cap

The marine-terminating outlet in Basin 3, Austfonna ice cap, has been accelerating since the mid-1990s. Stepwise multi-annual acceleration associated with seasonal summer speed-up events was observed before the outlet entered the basin-wide surge in autumn 2012. We used multiple numerical models to explore hydrologic activation mechanisms for the surge behaviour. A continuum ice dynamic model was used to invert basal friction coefficient distributions using the control method and observed surface velocity data between April 2012 and July 2014. This has provided input to a discrete element model capable of simulating individual crevasses, with the aim of finding locations where meltwater entered the glacier during the summer and reached the bed. The possible flow paths of surface meltwater reaching the glacier bed as well as those of meltwater produced at the bed were calculated according to the gradient of the hydraulic potential. The inverted friction coefficients show the "unplugging" of the stagnant ice front and expansion of low-friction regions before the surge reached its peak velocity in January 2013. Crevasse distribution reflects the basal friction pattern to a high degree. The meltwater reaches the bed through the crevasses located above the margins of the subglacial valley and the basal melt that is generated mainly by frictional heating flows either to the fast-flowing units or potentially accumulates in an overdeepened region. Based on these results, the mechanisms facilitated by basal meltwater production, crevasse opening and the routing of meltwater to the bed are discussed for the surge in Basin 3.Peer reviewe

From high friction zone to frontal collapse: dynamics of an ongoing tidewater glacier surge, Negribreen, Svalbard

Abstract Negribreen, a tidewater glacier located in central eastern Svalbard, began actively surging after it experienced an initial collapse in summer 2016. The surge resulted in horizontal surface velocities of more than 25 m d −1 , making it one of the fastest-flowing glaciers in the archipelago. The last surge of Negribreen likely occurred in the 1930s, but due to a long quiescent phase, investigations of this glacier have been limited. As Negribreen is part of the Negribreen Glacier System, one of the largest glacier systems in Svalbard, investigating its current surge event provides important information on surge behaviour among tidewater glaciers within the region. Here, we demonstrate the surge development and discuss triggering mechanisms using time series of digital elevation models (1969–2018), surface velocities (1995–2018), crevasse patterns and glacier extents from various data sources. We find that the active surge results from a four-stage process. Stage 1 (quiescent phase) involves a long-term, gradual geometry change due to high subglacial friction towards the terminus. These changes allow the onset of Stage 2, an accelerating frontal destabilization, which ultimately results in the collapse (Stage 3) and active surge (Stage 4)

METALS IN THE ICM: WITNESSES OF CLUSTER FORMATION AND EVOLUTION

The baryonic composition of galaxy clusters and groups is dominated by a hot, X-ray emitting Intra-Cluster Medium (ICM). The mean metallicity of the ICM has been found to be roughly 0.3 ÷ 0.5 times the solar value, therefore a large fraction of this gas cannot be of purely primordial origin. Indeed, the distribution and amount of metals in the ICM is a direct consequence of the past history of star formation in the cluster galaxies and of the processes responsible for the injection of enriched material into the ICM. We here shortly summarize the current views on the chemical enrichment, focusing on the observational evidence in terms of metallicity measurements in clusters, spatial metallicity distribution and evolution, and expectations from future missions

Bridges over troubled waters: an interdisciplinary framework for evaluating the interconnectedness within fragmented domestic flood risk management systems

Diversification of strategies in Flood Risk Management (FRM) is widely regarded as a necessary step forward in terms of lessening the likelihood and magnitude of flooding, as well as minimizing the exposure of people and property, and in turn the disruption, economic damage, health impacts and other adverse consequences that ensue when floods occur. Thus, diversification is often heralded as an essential condition for enhancing societal resilience to flooding. However, an inevitable consequence of diversifying strategies and practices in FRM is that it can lead to fragmentation within FRM systems, in terms of the distribution of responsibilities between actors and governing rules enacted within different policy domains. This can prove detrimental to the effectiveness of FRM. Building upon the notion of fragmentation developed in legal and governance literature, this paper introduces the concept of ‘bridging mechanisms’, i.e. instruments that remedy fragmentation by enhancing interconnectedness between relevant actors through information transfer, coordination and cooperation. This paper develops a typology of both fragmentation and bridging mechanisms and analyzes their relations, partly drawing upon empirical research conducted within the EU ‘STAR-FLOOD’ project. In turn, this paper outlines a novel interdisciplinary methodological framework for evaluating the degree and quality of the interconnectedness within fragmented domestic FRM systems. A pragmatic, flexible and broadly applicable tool, this framework is both suited for academic purposes, as well as for practically oriented analysis and (re)development of fragmented FRM systems, and potentially other fragmented systems, within the EU and abroad

[Letter to editor] Shedding of bevacizumab in tumour cells derived extracellular vesicles as a new therapeutic escape mechanism in glioblastoma

Glioblastoma (GBM) is the most aggressive type of primary brain tumours. Anti-angiogenic therapies (AAT), such as bevacizumab, have been developed to target the tumour blood supply. However, GBM presents mechanisms of escape from AAT activity, including a speculated direct effect of AAT on GBM cells. Furthermore, bevacizumab can alter the intercellular communication of GBM cells with their direct microenvironment. Extracellular vesicles (EVs) have been recently described as main acts in the GBM microenvironment, allowing tumour and stromal cells to exchange genetic and proteomic material. Herein, we examined and described the alterations in the EVs produced by GBM cells following bevacizumab treatment. Interestingly, bevacizumab that is able to neutralise GBM cells-derived VEGF-A, was found to be directly captured by GBM cells and eventually sorted at the surface of the respective EVs. We also identified early endosomes as potential pathways involved in the bevacizumab internalisation by GBM cells. Via MS analysis, we observed that treatment with bevacizumab induces changes in the EVs proteomic content, which are associated with tumour progression and therapeutic resistance. Accordingly, inhibition of EVs production by GBM cells improved the anti-tumour effect of bevacizumab. Together, this data suggests of a potential new mechanism of GBM escape from bevacizumab activity

Dealing with change and uncertainty within the regulatory frameworks for flood defense infrastructure in selected European countries

Whereas existing literature on the interactions between law, adaptive governance and resilience in the water sector often focuses on quality or supply issues, this paper addresses adaptation in national water laws in relation to increasing flood risks. In particular, this paper analyzes the extent to which legal rules governing flood defense infrastructure in a selection of European countries (Sweden, France, England and the Netherlands) allow for response and adaptation to change and uncertainty. While there is evidence that the legal rules on the development of new infrastructure require that changing conditions be considered, the adaptation of existing infrastructure is a more complicated matter. Liability rules fail to adequately address damages resulting from causes external to the action or inaction of owners and managers, in particular extreme events. A trend towards clearer, and in some cases, increased public powers to ensure the safety of flood defense infrastructure is observed. The paper concludes that legal rules should ensure not only that decisions to build flood defenses are based on holistic and future-oriented assessments, but also that this is reflected in the implementation and operation of these structures