159 research outputs found
What drives the recent intensified vegetation degradation in Mongolia - Climate change or human activity?
This study examines the course and driving forces of recent vegetation change
in the Mongolian steppe. A sediment core covering the last 55 years from a
small closed-basin lake in central Mongolia was analyzed for its multi-proxy
record at annual resolution. Pollen analysis shows that highest abundances of
planted Poaceae and highest vegetation diversity occurred during 1977–1992,
reflecting agricultural development in the lake area. A decrease in diversity
and an increase in Artemisia abundance after 1992 indicate enhanced vegetation
degradation in recent times, most probably because of overgrazing and farmland
abandonment. Human impact is the main factor for the vegetation degradation
within the past decades as revealed by a series of redundancy analyses, while
climate change and soil erosion play subordinate roles. High Pediastrum (a
green algae) influx, high atomic total organic carbon/total nitrogen (TOC/TN)
ratios, abundant coarse detrital grains, and the decrease of δ13Corg and δ15N
since about 1977 but particularly after 1992 indicate that abundant
terrestrial organic matter and nutrients were transported into the lake and
caused lake eutrophication, presumably because of intensified land use. Thus,
we infer that the transition to a market economy in Mongolia since the early
1990s not only caused dramatic vegetation degradation but also affected the
lake ecosystem through anthropogenic changes in the catchment area
The E. Coli Pyrogen Test in human liver disease
Peer Reviewe
Big Data and Television Broadcasting. A Critical Reflection on Big Data’s Surge to Be-come a New Techno-Economic Paradigm and its Impacts on the Concept of the «Ad-dressable Audience»
The paper explores how big data creates challenges and opportunities to enhance value relationships be-tween TV broadcasters, audiences and advertisers in digital television broadcasting. It finds that research into big data requires much closer attention to critical issues in the social and cultural sciences – with a fo-cus on media and communication studies and its subfield media management – to inspire our understand-ing that big data would perfectly fit the dominant «techno-economic paradigm», a meta-narrative for a substantial technological revolution that has the power to bring about a transformation across the board in ways that when new technologies diffuse, they multiply their impact across the economy and eventually modifies the socio-institutional structures. While asking how big data adds value to a broadcaster’s decision on corporate strategies in Big-Data driven TV is legitimate and important, we remain skeptical as to what effectively is to be gleaned from big data in broadcast TV This is because the socio-cultural dimensions are greatly unresolved. Notably, the corporate strategies of the «addressable audience» or audience com-modification, whereby audiences are effectively sold as mere datacommodities to broadcasters and adver-tisers, must be observed critically
Musik im ”Quality TV”
Die Beiträge untersuchen den Einsatz von Musik in zeitgenössischen Fernsehserien.A collection of articles dealing with music in contemporary TV shows
Bildung gestalten im Homeschooling
"Lehrer:innen haben kreative Ideen und die individuelle Fähigkeit, den Unterricht im Homeschooling erfolgreich zu gestalten!". Zu dieser Überzeugung gelangen die Autor:innen. Sie belegen ihre positive Bilanz mit einer Studie, in der sie von Lehrkräften selbst erstellte und in der Praxis erprobte Lernmaterialien aus der Zeit des Homeschoolings während der Corona-Pandemie in den Jahren 2020 und 2021 empirisch analysieren und auswerten. So ergeben sich neben interessanten Ergebnissen hinsichtlich der Gestaltung dieser Materialien abwechslungsreiche und fächerübergreifende Fallbeispiele als Anregungen für den eigenen Unterricht. Die Autor:innen legen dar, welche digitalen Lernangebote den Schüler:innen im Homeschooling gemacht wurden. Die im Buch ausgewählten Fallbeispiele dienen als Inspiration für die eigene Lehr- und Lernsituation. Dabei kann die Lektüre (angehende) Lehrkräfte dabei unterstützen, eigene Ideen zu entwickeln, neue Perspektiven einzunehmen und bereitgestellte Beispiele weiterzudenken. (DIPF/Orig.
Partizipative Mediendidaktik als Gateway für ziviles Engagement von Heranwachsenden und die Rolle persönlicher Lernumgebungen
Ausgehend vom Modell von Gotlieb und Sarge (2021), in welchem Attribute partizipativer Mediennutzung (sich ausdrücken, sich darstellen und mit anderen zusammenarbeiten) mit motivationalen Prozessen der Selbstbestimmung sowie der Ausbildung zivilgesellschaftlicher Fähigkeiten verbunden werden, modelliert dieser theoretisch-konzeptionelle Beitrag den Zusammenhang zwischen partizipativen Praktiken von Kindern und Jugendlichen in digitalen Medienumgebungen und ihrem zivilem Engagement. Dabei wird auf das heuristische Strukturmodell einer partizipativen Mediendidaktik nach Mayrberger (2019) sowie Überlegungen zum selbstbestimmten Lernen zurückgegriffen, um kommunikationswissenschaftliche Konzepte mit medienpädagogischen und bildungswissenschaftlichen Ansätzen zu kombinieren. Die Herausbildung und Förderung partizipativer Fähigkeiten von Heranwachsenden im Rahmen partizipativer Mediendidaktik in formalen und informellen Bildungskontexten begreifen wir demnach als potenziellen Zugang für ziviles, staatsbürgerliches Engagement der jungen Zielgruppe. Vor diesem Hintergrund argumentieren wir, dass der Gestaltung der persönlichen Lernumgebung (PLE) und der damit verbundenen Zusammenstellung medialer Arrangements in unterschiedlich gelagerten Lernkontexten durch die Heranwachsenden eine wichtige Bedeutung zukommt. Anhand quantitativer Befragungsdaten zur Nutzung des Study Webs im Rahmen selbstbestimmten Lernens exploriert der Beitrag beispielhaft das Potenzial digitaler persönlicher Lernumgebungen und damit partizipativen Handelns in Bildungszusammenhängen für das zivile Engagement Heranwachsender
Quality TV and Social Distinction: An Experiment on How Complex Television Series Valorize Their Users
This paper addresses the question as to whether serial quality TV has the potential to valorize its fans. We draw on Bourdieu’s theory of distinction, assuming that demonstrated preference for a specific cultural taste has consequences for the attribution of capital endowment overall, and especially within an adept group. These assumptions are tested via a 3 (preference for high-culture vs. conventional television vs. quality TV series) x 1 online experiment with between subject design plus control group (N = 389). Results showed that conspicuously favouring serial quality TV has the potential to function as a distinctive sign – at least to some extent. Significantly more cultural capital is ascribed to a quality TV fan than to a person showing a preference for conventional television. Within a certain group of connoisseurs, a quality TV taste is even worth as much as a preference for high-culture. Implications are discussed with regard to the theory of distinction and quality TV series as the object of investigation
Quantitative reconstruction of precipitation changes on the NE Tibetan Plateau since the Last Glacial Maximum – extending the concept of pollen source area to pollen-based climate reconstructions from large lakes
Pollen records from large lakes have been used for quantitative
palaeoclimate reconstruction, but the influences that lake size (as a result
of species-specific variations in pollen dispersal patterns that smaller
pollen grains are more easily transported to lake centre) and taphonomy have
on these climatic signals have not previously been systematically
investigated. We introduce the concept of pollen source area to pollen-based
climate calibration using the north-eastern Tibetan
Plateau as our study area. We present a pollen data set collected from large
lakes in the arid to semi-arid region of central Asia. The influences that
lake size and the inferred pollen source areas have on pollen compositions
have been investigated through comparisons with pollen assemblages in
neighbouring lakes of various sizes. Modern pollen samples collected from
different parts of Lake Donggi Cona (in the north-eastern part of the
Tibetan Plateau) reveal variations in pollen assemblages within this large
lake, which are interpreted in terms of the species-specific dispersal and
depositional patterns for different types of pollen, and in terms of fluvial
input components. We have estimated the pollen source area for each lake
individually and used this information to infer modern climate data with
which to then develop a modern calibration data set, using both the
multivariate regression tree (MRT) and weighted-averaging partial least
squares (WA-PLS) approaches. Fossil pollen data from Lake Donggi Cona have
been used to reconstruct the climate history of the north-eastern part of
the Tibetan Plateau since the Last Glacial Maximum (LGM). The mean annual
precipitation was quantitatively reconstructed using WA-PLS: extremely dry
conditions are found to have dominated the LGM, with annual precipitation of
around 100 mm, which is only 32% of present-day precipitation. A
gradually increasing trend in moisture conditions during the Late Glacial is
terminated by an abrupt reversion to a dry phase that lasts for about 1000 yr
and coincides with "Heinrich event 1" in the North Atlantic
region. Subsequent periods corresponding to the Bølling/Allerød
interstadial, with annual precipitation (<i>P</i><sub>ann</sub>) of about 350 mm, and the
Younger Dryas event (about 270 mm <i>P</i><sub>ann</sub>) are followed by moist
conditions in the early Holocene, with annual precipitation of up to 400 mm.
A drier trend after 9 cal. ka BP is followed by a second wet phase in the
middle Holocene, lasting until 4.5 cal. ka BP. Relatively steady conditions
with only slight fluctuations then dominate the late Holocene, resulting in
the present climatic conditions. The climate changes since the LGM have been
primarily driven by deglaciation and fluctuations in the intensity of the
Asian summer monsoon that resulted from changes in the Northern Hemisphere
summer solar insolation, as well as from changes in the North Atlantic
climate through variations in the circulation patterns and intensity of the
westerlies
LegacyClimate 1.0: A dataset of pollen-based climate reconstructions from 2594 Northern Hemisphere sites covering the late Quaternary
Here we describe the LegacyClimate 1.0, a dataset of the reconstruction of mean July temperature (TJuly), mean annual temperature (Tann), and annual precipitation (Pann) from 2594 fossil pollen records from the Northern Hemisphere spanning the entire Holocene with some records reaching back to the Last Glacial. Two reconstruction methods, the Modern Analogue Technique (MAT) and Weighted-Averaging Partial-Least Squares regression (WA-PLS) reveal similar results regarding spatial and temporal patterns. To reduce the impact of precipitation on temperature reconstruction and vice versa, we also provide reconstructions using tailored modern pollen data limiting the range of the corresponding other climate variables. We assess the reliability of the reconstructions using information from the spatial distributions of the root-mean squared error of prediction and reconstruction significance tests. The dataset is beneficial for climate proxy synthesis studies and to evaluate the output of climate models and thus help to improve the models themselves. We provide our compilation of reconstructed TJuly, Tann, and Pann as open-access datasets at PANGAEA (https://doi.pangaea.de/10.1594/PANGAEA.930512; Herzschuh et al., 2021). R code for the reconstructions is provided at Zenodo (https://doi.org/10.5281/zenodo.5910989; Herzschuh et al., 2022), including harmonized open-access modern and fossil datasets used for the reconstructions, so that customized reconstructions can be easily established
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