Editorial zum Tagungsband: Spannungsfelder und blinde Flecken. Medienpädagogik zwischen Emanzipationsanspruch und Diskursvermeidung

Die erziehungswissenschaftliche Auseinandersetzung mit Medien hat in Deutschland eine lange und vielfältige Tradition. In den letzten Jahrzehnten hat sich die Medienpädagogik zu einer eigenständigen akademischen (Teil-)Disziplin entwickelt, die in der (Fach-)Öffentlichkeit wahrgenommen wird und sich aktiv in aktuelle gesellschaftliche Diskurse einbringt. Sichtbar wird die Etablierung als Fach u. a. daran, dass an einer Reihe von Hochschulen Professuren geschaffen wurden, die für medienpädagogische Studienelemente oder -gänge und/oder Zusatzausbildungen verantwortlich sind. Der gestiegene Stellenwert der Disziplin zeigt sich auch an ihrer Rolle in der Deutschen Gesellschaft für Erziehungswissenschaft, innerhalb derer sie sich von einer «Arbeitsgemeinschaft auf Zeit» (Mitte der 1990er-Jahre) zu einer eigenständigen Sektion (seit 2010) entwickelt hat. Angesichts der gegenwärtig zu beobachtenden Entwicklungen im Medienbereich (u. a. Digitalisierung, Globalisierung, Algorithmisierung), deren Folgen für gesellschaftliche und pädagogische Prozesse und Bereiche kaum zu unterschätzen sind, erstaunt es, dass die Medienpädagogik bis heute dazu neigt, Rechtfertigungsstrategien für die eigenen Existenz zu generieren. Bei einer kritischen Betrachtung (z. B. der universitären Stellenpolitik) ist aber zu konstatieren, dass sich die Medienpädagogik auch 40 Jahre nach dem Erscheinen von Dieter Baackes wegweisender Schrift Kommunikation und Kompetenz ihrer Anerkennung und festen Verankerung im akademischen Feld tatsächlich noch immer nicht sicher sein kann. Eine Ursache hierfür liegt möglicherweise in der noch immer grossen (und oftmals geradezu zelebrierten) Heterogenität des Faches. So sind die unterschiedlichen Traditionslinien des pädagogischen Umgangs mit Medien, die mitunter nur bedingt miteinander vereinbar sind, bis heute zu beobachten und wirkmächtig. Zu unterscheiden ist hierbei bspw. eine auf Emanzipation, kommunikative Kompetenz und Selbstermächtigung orientierte Linie, die sich in ausserschulischen Settings subjekt- und ressourcenorientiert die Medien als Instrumente subversiver Strategien und/oder der Identitätskonstruktion angeeignet hat. Oft nur bedingt an diese anschlussfähig ist eine schulpädagogische Linie, die ihren Ausgang bei der ‹Film- und Medienerziehung› genommen hat und inzwischen stärker auf Kompetenzerwerb fokussiert. Daneben findet sich dann noch eine (vielfältig ausdifferenzierte) ‹Mediendidaktik›, die immer wieder technologie-euphorisch innovatives Lernen versprochen hat. Positiv gewendet, zeigt bereits diese kleine Skizze, dass die Medienpädagogik als erziehungswissenschaftliche Disziplin darauf verweisen kann, wie intensiv Theoriebildung, Forschung und Praxis gegenwärtig in einem breiten Spektrum von Ansätzen, Forschungsschwerpunkten und ‹Schulen› vollzogen wird. Das Fach ist also sehr lebendig – erscheint aber aus der Perspektive externer Beobachter möglicherweise auch als diffus

Global complexity: some remarks to the "Author meets critic session" at the DGS congress in 2004

Der Beitrag dokumentiert die Diskussion auf der "Author Meets Critic"-Veranstaltung zu John Urrys "Sociology Beyond Societies" auf dem 32. Kongress der Deutschen Gesellschaft für Soziologie (2004). Zunächst erläutert Urry den Grundgedanken seines Ansatzes, der auf eine Aufhebung der Trennung zwischen Naturwissenschaften und Gesellschaftswissenschaften hinausläuft. Unter dem Leitbild "Komplexität" wird die Analyse physischer und sozialer Welten integriert. Dabei werden auch Elemente von Hardt/Negris "Empire und Multitude"-Konzept aufgegriffen. Der Begriff der Globalen Komplexität steht auch im Mittelpunkt der Kommentare von Junge und Schwengel zu Urrys Buch. (ICE

Characterization of a preclinical PET insert in a 7 tesla MRI scanner: beyond NEMA testing

[EN] This study evaluates the performance of the Bruker positron emission tomograph (PET) insert combined with a BioSpec 70/30 USR magnetic resonance imaging (MRI) scanner using the manufacturer acceptance protocol and the NEMA NU 4-2008 for small animal PET. The PET insert is made of 3 rings of 8 monolithic LYSO crystals (50 x 50 x 10 mm(3)) coupled to silicon photomultipliers (SiPM) arrays, conferring an axial and transaxial FOV of 15 cm and 8 cm. The MRI performance was evaluated with and without the insert for the following radiofrequency noise, magnetic field homogeneity and image quality. For the PET performance, we extended the NEMA protocol featuring system sensitivity, count rates, spatial resolution and image quality to homogeneity and accuracy for quantification using several MRI sequences (RARE, FLASH, EPI and UTE). The PET insert does not show any adverse effect on the MRI performances. The MR field homogeneity is well preserved (Diameter Spherical Volume, for 20 mm of 1.98 +/- 4.78 without and -0.96 +/- 5.16 Hz with the PET insert). The PET insert has no major effect on the radiofrequency field. The signal-to-noise ratio measurements also do not show major differences. Image ghosting is well within the manufacturer specifications (<2.5%) and no RF noise is visible. Maximum sensitivity of the PET insert is 11.0% at the center of the FOV even with simultaneous acquisition of EPI and RARE. PET MLEM resolution is 0.87 mm (FWHM) at 5 mm off-center of the FOV and 0.97 mm at 25 mm radial offset. The peaks for true/noise equivalent count rates are 410/240 and 628/486 kcps for the rat and mouse phantoms, and are reached at 30.34/22.85 and 27.94/22.58 MBq. PET image quality is minimally altered by the different MRI sequences. The Bruker PET insert shows no adverse effect on the MRI performance and demonstrated a high sensitivity, sub-millimeter resolution and good image quality even during simultaneous MRI acquisition.We acknowledge the KU Leuven core facility, Molecular Small Animal Imaging Center (MoSAIC), for their support with obtaining scientific data presented in this paper. This work was supported by Stichting tegen Kanker (2015-145, Christophe M. Deroose) and Hercules foundation (AKUL/13/029, Uwe Himmelreich) for the purchase of the PET and MRI equipment respectively. The work was supported by the following funding organizations: European Commission for the PANA project (H2020-NMP-2015-two-stage, grant 686009) and the European ERA-NET project 'CryptoView' (3rd call of the FP7 program Infect-ERA).Gsell, W.; Molinos, C.; Correcher, C.; Belderbos, S.; Wouters, J.; Junge, S.; Heidenreich, M.... (2020). Characterization of a preclinical PET insert in a 7 tesla MRI scanner: beyond NEMA testing. 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Seminars in Nuclear Medicine, 48(4), 332-347. doi:10.1053/j.semnuclmed.2018.02.011Maramraju, S. H., Smith, S. D., Junnarkar, S. S., Schulz, D., Stoll, S., Ravindranath, B., … Schlyer, D. J. (2011). Small animal simultaneous PET/MRI: initial experiences in a 9.4 T microMRI. Physics in Medicine and Biology, 56(8), 2459-2480. doi:10.1088/0031-9155/56/8/009Molinos, C., Sasser, T., Salmon, P., Gsell, W., Viertl, D., Massey, J. C., … Heidenreich, M. (2019). Low-Dose Imaging in a New Preclinical Total-Body PET/CT Scanner. Frontiers in Medicine, 6. doi:10.3389/fmed.2019.00088Nagy, K., Tóth, M., Major, P., Patay, G., Egri, G., Häggkvist, J., … Gulyás, B. (2013). Performance Evaluation of the Small-Animal nanoScan PET/MRI System. Journal of Nuclear Medicine, 54(10), 1825-1832. doi:10.2967/jnumed.112.119065Nanni, C., & Torigian, D. A. (2008). Applications of Small Animal Imaging with PET, PET/CT, and PET/MR Imaging. PET Clinics, 3(3), 243-250. doi:10.1016/j.cpet.2009.01.002Omidvari, N., Cabello, J., Topping, G., Schneider, F. R., Paul, S., Schwaiger, M., & Ziegler, S. I. (2017). PET performance evaluation of MADPET4: a small animal PET insert for a 7 T MRI scanner. Physics in Medicine & Biology, 62(22), 8671-8692. doi:10.1088/1361-6560/aa910dOmidvari, N., Topping, G., Cabello, J., Paul, S., Schwaiger, M., & Ziegler, S. I. (2018). MR-compatibility assessment of MADPET4: a study of interferences between an SiPM-based PET insert and a 7 T MRI system. Physics in Medicine & Biology, 63(9), 095002. doi:10.1088/1361-6560/aab9d1Raylman, R. R., Majewski, S., Lemieux, S. K., Velan, S. S., Kross, B., Popov, V., … Marano, G. D. (2006). Simultaneous MRI and PET imaging of a rat brain. Physics in Medicine and Biology, 51(24), 6371-6379. doi:10.1088/0031-9155/51/24/006Roncali, E., & Cherry, S. R. (2011). Application of Silicon Photomultipliers to Positron Emission Tomography. Annals of Biomedical Engineering, 39(4), 1358-1377. doi:10.1007/s10439-011-0266-9Schug, D., Lerche, C., Weissler, B., Gebhardt, P., Goldschmidt, B., Wehner, J., … Schulz, V. (2016). Initial PET performance evaluation of a preclinical insert for PET/MRI with digital SiPM technology. Physics in Medicine and Biology, 61(7), 2851-2878. doi:10.1088/0031-9155/61/7/2851Shao, Y., Cherry, S. R., Farahani, K., Meadors, K., Siegel, S., Silverman, R. W., & Marsden, P. K. (1997). Simultaneous PET and MR imaging. Physics in Medicine and Biology, 42(10), 1965-1970. doi:10.1088/0031-9155/42/10/010Steinert, H. C., & von Schulthess, G. K. (2002). Initial clinical experience using a new integrated in-line PET/CT system. The British Journal of Radiology, 75(suppl_9), S36-S38. doi:10.1259/bjr.75.suppl_9.750036Stortz, G., Thiessen, J. D., Bishop, D., Khan, M. S., Kozlowski, P., Retière, F., … Sossi, V. (2017). Performance of a PET Insert for High-Resolution Small-Animal PET/MRI at 7 Tesla. Journal of Nuclear Medicine, 59(3), 536-542. doi:10.2967/jnumed.116.187666Townsend, D. W. (2008). Combined Positron Emission Tomography–Computed Tomography: The Historical Perspective. Seminars in Ultrasound, CT and MRI, 29(4), 232-235. doi:10.1053/j.sult.2008.05.006Vandenberghe, S., & Marsden, P. K. (2015). PET-MRI: a review of challenges and solutions in the development of integrated multimodality imaging. Physics in Medicine and Biology, 60(4), R115-R154. doi:10.1088/0031-9155/60/4/r115Vaquero, J. J., & Kinahan, P. (2015). Positron Emission Tomography: Current Challenges and Opportunities for Technological Advances in Clinical and Preclinical Imaging Systems. Annual Review of Biomedical Engineering, 17(1), 385-414. doi:10.1146/annurev-bioeng-071114-040723Von Schulthess, G. K., & Schlemmer, H.-P. W. (2008). A look ahead: PET/MR versus PET/CT. 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Working group on bycatch of protected species (WGBYC 2021)

The Working Group on Bycatch of Protected Species (WGBYC) was established in 2007 and collates and analyses information from across the Northeast Atlantic and adjacent sea areas (Baltic, Mediterranean and Black Seas) related to the bycatch of marine mammals, seabirds, turtles, and sensitive fish species in commercial fishing operations. Sensitive fish species were not considered at the 2021 meeting pending approval from the ICES Advisory Committee (ACOM) on fish species lists of bycatch interest that were developed at the ICES Workshop on Fish of Conservation and Bycatch Relevance (WKCOFIBYC) in 2020. WGBYC seeks to describe and improve under-standing of the likely impacts of fishing activities on affected populations at biologically relevant scales, to inform on the suitability of existing at-sea monitoring programmes for the quantification of robust bycatch estimates, and to collate information on and coordinate bycatch mitigation efforts at an international scale. In 2021, the WG met by correspondence to address eight Terms of Reference (ToR), including a data scoping exercise as part of a special request on seabird bycatch from the North East Atlantic Fisheries Commission (NEAFC), which concluded that there was insufficient bycatch monitoring data from NEAFC waters to warrant further analyses at this time. The report also provides an overview of monitoring and fishing effort data contained in the WGBYC database for 2019 and 2020. This showed that during 2020, in most geographical areas of relevance, at-sea monitoring effort was significantly affected by the Covid-19 pandemic. Specific analyses were carried out to describe potential fisheries impacts (reported bycatch numbers, min/max bycatch rates and/or mortality estimates) for harbour seal in the Greater North Sea ecoregion and parts of the Baltic ecoregion, three turtle species in four Mediterranean ecoregions and in the Azores and Bay of Biscay and Iberian Coast ecoregions, and several seabird species in six ecoregions (Adriatic, Baltic, Bay of Biscay and Iberian Coast, Celtic Seas, Greater North Sea and Icelandic Waters). A risk-based approach, developed by WGBYC in 2020 to highlight monitoring gaps, was expanded using information from multiple sources and identified several high-risk métiers for bycatch which are relatively under-sampled by existing data collection programmes. Several members of WGBYC also participated simultaneously in the ICES Workshop on Estimation of Mortality of Marine Mammals due to Bycatch (WKMOMA) which ran over schedule due to data issues. Data used by WGBYC on fishing effort, at-sea monitoring effort and bycatch records are primarily acquired through an ICES dedicated data call which has been issued annually to all ICES member states since 2018 and all non-ICES EU coastal states from 2021. Although data quality and quantity are improving, WGBYC reiterate that significant gaps remain in data collection efforts and in data resolution, that limits the Working Group’s ability to provide useful assessments of the likely impacts of fishing activity across a wide range of protected species and areas. WGBYC note that broadscale low level monitoring programmes may be insufficient to highlight very rare bycatch occurrences for populations at low abundance and/or low susceptibility to by-catch, but which could have significant population levels impacts

Working group on bycatch of protected species (WGBYC 2022)

The Working Group on Bycatch of Protected Species (WGBYC) was established in 2007 and collates and analyses information from across the Northeast Atlantic and adjacent sea areas (Baltic, Mediterranean and Black Seas) related to the bycatch in commercial fishing operations of pro-tected and sensitive species including marine mammals, seabirds, turtles and sensitive fish spe-cies. WGBYC seeks to describe and improve understanding of the likely impacts of fishing activities on affected populations, to inform on the suitability of existing at-sea monitoring programmes for assessing sensitive species bycatch, and to collate information on bycatch mitigation efforts. In 2022, the WG hybrid meeting addressed seven Terms of Reference (ToR). The report provides an overview of data collection activities during 2021 including details of reported monitoring and fishing effort data, and bycatch records that were submitted to the WGBYC database in 2022 following a formal data call. Data were requested from 17 of the 20 ICES countries, six EU Mediterranean countries and two EU Black Sea countries. 24 of the 25 contacted countries submitted data. WGBYC developed a new approach for evaluating and assessing bycatch across the full range of relevant taxa by considering a range of criteria, including data quality, within group expertise and the existence of management/conservation objectives. Preliminary results based on a selec-tion of 35 Ecoregion/species/métier level 4 combinations indicated that just 9 had low monitoring bias, and also highlighted that clear conservation objectives are generally lacking for most spe-cies and areas. This approach will be further developed by WGBYC to underpin the requirements of the agreement between ICES and DGMARE for the provision of annual advice on bycatch. WGBYC provided qualitative information for several species/populations of marine mammals, seabirds, turtles and fish, that are currently considered to be at significant risk due to fisheries bycatch, but because of their rarity are not well represented in existing fisheries monitoring da-tasets. A risk-based approach to highlight monitoring gaps and inform coordinated sampling designs was further developed and provided useful insights into which métiers may be under-sampled by existing at-sea data collection programmes with respect to sensitive species bycatch. WGBYC prepared tables and plots describing data reporting in 2021, multi-annual bycatch rates and trends in fishing effort, to contribute to the 2022 recurrent and fisheries overviews advice drafting process

Genetic landscape of pediatric acute liver failure of indeterminate origin.

BACKGROUND AIMS Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, main causes are viral infections (12-16%) and inherited metabolic diseases (14-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. METHODS With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF (RALF). WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (46%), and in children with RALF (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8) and DGUOK (n=7) were the most frequent findings. When categorizing, most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%) and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplants. CONCLUSION This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics

Genetic landscape of pediatric acute liver failure of indeterminate origin

BACKGROUND AND AIMS: Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. APPROACH AND RESULTS: With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS: In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation. CONCLUSIONS: This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics

Reducing the impact of metal impurities in block-cast mc Silicon

The detrimental influence of transition metals on minority carrier lifetime in solar cells and thus solar cell performance is up to now not fully understood. In this paper we would like to contribute some new results on this topic concerning the gettering and deactivation of the transition metals iron (Fe) and copper (Cu) in block cast multicrystalline (mc) Si material. The investigated processing steps include extended POCl3 gettering and hydrogenation by firing of a PECVD (Plasma-Enhanced Chemical Vapor Deposition) silicon nitride (SiNx:H). They are carried out on neighboring wafers using processing conditions which are derived from the standard photolithography based process at the University of Konstanz (UKN). Sets of neighboring wafers are selected from bottom, middle and top of an ingot, respectively, to address the varying impurity concentrations e.g. due to segregation during ingot casting. To extract the specific influence of the transition metals, wafers from intentionally contaminated mc material were examined. Hydrogenation clearly turned out to have the biggest positive influence on the contaminated material, while extended gettering showed non-uniform results. In some cases an improvement was observed, but also degradation of the bulk material occurred

Emitter optimization for mono- and multicrystalline silicon : a study of emitter saturation currents

In this work the influence of varied diffusion parameters for an industrial open tube POCl3 diffusion furnace upon the emitter saturation current density on monocrystalline silicon is investigated. Further on, the effect of phosphorus gettering on multicrystalline silicon and on the sheet resistance on both mono- and multicrystalline silicon is under investigation. In addition, diffusion profiles are determined using the ECV (Electrochemical Capacitance Voltage) technique. Aim of this work is to enhance the performance of lowly doped emitters (80- 140 Ω/sq) applied in a photolithography based high efficiency solar cell process with special respect to defect-rich block cast multicrystalline silicon material. Understanding the influence of temperature, time and gas flow variations during the diffusion process is very important to enhance solar cell performance especially for mc silicon. For such materials the POCl3 gettering effect and the defect kinetics during the diffusion and the cool down phase after the diffusion are of major interest besides the reliable contact formation and low emitter saturation currents resulting in a good blue response of solar cells. The experiments performed in this work demonstrate that different mono- and multicrystalline silicon materials can benefit from adapted diffusion recipes in terms of significantly reduced emitter saturation currents and increased bulk lifetimes resulting in enhanced solar cell efficiencies

Evaluation of processing steps regarding lifetime of iron/copper contaminated mc Si wafers

It is well known that gettering and passivation steps during solar cell processing enhance the minority charge carrier lifetime (here simply referred to as lifetime) in the silicon wafers. The purpose of this work is to study the influence of different solar cell processing steps on lifetime depending on the impurity level. Therefore neighboring wafers of standard multicrystalline as well as differently contaminated ingots were treated with various POCl3-diffusion and/or hydrogenation steps. The sequence of treatments is varied to check the effect of each processing step individually and to investigate if an individual processing step is less or more effective if another step was applied before. Afterwards these wafers were examined by microwave photoconductance decay measurements (μPCD). The gained results might be important for defect engineering and the development of an optimized solar cell process on cost effective and impurity-rich silicon material to reduce the detrimental impact of metal impurities on solar cell parameters