228 research outputs found
Albian to Turonian agglutinated foraminiferal assemblages of the Lower Saxony Cretaceous sub-basins â implications for sequence stratigraphy and paleoenvironmental interpretation
Albian to Turonian carbonate deposits at three different locations of the
Lower Saxony Cretaceous and thereby of the European mid-Cretaceous epeiric
shelf sea were investigated for their fossil agglutinated foraminiferal
fauna. In this study, 71Â samples from two quarries and three drill cores
were treated with formic acid, which enabled the study of agglutinated
foraminiferal assemblages even in highly lithified limestones. In total, 114
species were determined and classified as belonging to nine morphogroups. In
general, four agglutinated foraminiferal assemblages are distinguished: (1)Â an uppermost Albianâlowermost Cenomanian assemblage from the Wunstorf drill
cores, with the dominant taxa
Bathysiphon spp., Nothia spp., Psammosphaera fusca, Reophax subfusiformis, Bulbobaculites problematicus, Tritaxia tricarinata, Flourensina intermedia, Vialovella frankei, Arenobulimina truncata, and Voloshinoides advenus; (2)Â a Cenomanian
assemblage from the Baddeckenstedt quarry and Wunstorf drill cores, with
Ammolagena clavata, Tritaxia tricarinata, Vialovella frankei, Arenobulimina truncata, and Voloshinoides advenus; (3)Â an assemblage related to the CenomanianâTuronian Boundary Event in
Wunstorf and Söhlde dominated by Bulbobaculites problematicus; and (4) a Turonian assemblage in the
Wunstorf and Söhlde sections with high numbers of Ammolagena contorta, Repmanina charoides, Bulbobaculites problematicus, Gerochammina stanislawi, and
Spiroplectammina navarroana. The latest Albianâearliest Cenomanian assemblage consists of tubular,
globular, and elongate foraminiferal morphogroups which are typical for the
low- to mid-latitude slope biofacies. All other assemblages are composed of
elongate foraminiferal morphogroups with additionally globular forms in the
proximal settings of Baddeckenstedt and Söhlde or flattened planispiral
and streptospiral forms in more distal settings of Wunstorf. For these
assemblages, a new agglutinated foraminiferal biofacies named âmid-latitude
shelf biofaciesâ is proposed herein. Changes in the relative abundance of
different morphogroups can often be referred to single features of
depositional sequences. Furthermore, classical macro-bioevents, which are
often depositional-related, of the Lower Saxony Cretaceous seem to have a
micro-bioevent or acme equivalent of the agglutinated foraminiferal fauna.</p
Agglutinated foraminifera from the TuronianâConiacian boundary interval in Europe â paleoenvironmental remarks and stratigraphy
Agglutinated foraminiferal assemblages of the TuronianâConiacian from the
GSSP (Global Boundary Stratotype Section and Point) of SalzgitterâSalder (Subhercynian Cretaceous Basin, Germany) and
other sections, including BielefeldâOstwestfalendamm (MĂŒnsterland Cretaceous
Basin, Germany) and the DoverâLangdon Stairs (Anglo-Paris Basin, England), from
the temperate European shelf realm were studied in order to collect
additional stratigraphic and paleoenvironmental information. Stable carbon
isotopes were measured for the BielefeldâOstwestfalendamm section to
establish a reliable stratigraphic correlation with other sections. Highly
diverse agglutinated foraminiferal assemblages were obtained from sections
in the German basins, whereas the fauna from Dover is less rich in taxa and
less abundant. In the German basinal sections, a morphogroup
analysis of agglutinated foraminifera and the calculated diversities imply
normal marine settings and oligotrophic to mesotrophic bottom-water
conditions. Furthermore, acmes of agglutinated foraminifera correlate
between different sections and can be used for paleoenvironmental analysis.
Three acmes of the species Ammolagena contorta are recorded for the TuronianâConiacian
(perplexus to lower striatoconcentricus zones, lower scupini Zone, and hannovrensis Zone) and likely imply a shift to more
oligotrophic bottom-water conditions. In the upper scupini Zone below the
TuronianâConiacian boundary, an acme of Bulbobaculites problematicus likely indicates enhanced nutrient
availability.
In general, agglutinated foraminiferal morphogroups display a gradual shift
from Turonian oligotrophic environments towards more mesotrophic conditions
in the latest Turonian and Coniacian.</p
Increasing Dominance - the Role of Advertising, Pricing and Product Design
Despite the empirical relevance of advertising strategies in concentrated markets, the economics literature is largely silent on the effect of persuasive advertising
strategies on pricing, market structure and increasing (or decreasing) dominance. In a simple model of persuasive advertising and pricing with differentiated goods,
we analyze the interdependencies between ex-ante asymmetries in consumer appeal, advertising and prices. Products with larger initial appeal to consumers will
be advertised more heavily but priced at a higher level - that is, advertising and price discounts are strategic substitutes for products with asymmetric initial appeal.
We find that the escalating effect of advertising dominates the moderating effect of pricing so that post-competition market shares are more asymmetric than pre-competition differences in consumer appeal. We further find that collusive advertising (but competitive pricing) generates the same market outcomes, and that network effects lead to even more extreme market outcomes, both directly and via
the effect on advertising
Going means trouble and staying makes it double: the value of licensing recorded music online
This paper discusses whether a copyright compensation system (CCS) for recorded musicâendowing private Internet subscribers with the right to download and use works in return for a feeâwould be welfare increasing. It reports on the results of a discrete choice experiment conducted with a representative sample of the Dutch population consisting of 4986 participants. Under some conservative assumptions, we find that applied only to recorded music, a mandatory CCS could increase the welfare of rights holders and users in the Netherlands by over âŹ600 million per year (over âŹ35 per capita). This far exceeds current rights holder revenues from the market of recorded music of ca. âŹ144 million per year. A monthly CCS fee of ca. âŹ1.74 as a surcharge on Dutch Internet subscriptions would raise the same amount of revenues to rights holders as the current market for recorded music. With a voluntary CCS, the estimated welfare gains to users and rights holders are even greater for CCS fees below âŹ20 on the user side. A voluntary CCS would also perform better in the long run, as it could retain a greater extent of market coordination. The results of our choice experiment indicate that a well-designed CCS for recorded music would simultaneously make users and rights holders better off. This result holds even if we correct for frequently observed rates of overestimation in contingent valuation studies
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Cultural Capital and Attitudes Toward Homosexuals: Exploring the Relation Between Lifestyles and Homonegativity
This article explores the potential of cultural capital as explanatory factor in understanding homonegativity. Building on recent findings suggesting the need for a cultural component in understanding homonegativity, this article explores the relation between lifestyles (the measurable expression of cultural capital) and homonegativity. Using the âSocial-Cultural Changes in Flanders 2006â survey (a population-wide survey in Flanders, the northern part of Belgium), we observed that homonegativity is lowest in lifestyle clusters where cultural capital is higher. This effect, furthermore, is maintained even after controlling for other homonegativity correlates. These results suggest that cultural capital, expressed by lifestyles, is a valuable addition to the understanding of homonegativity
Coleta seletiva na RegiĂŁo Metropolitana de SĂŁo Paulo: impactos da PolĂtica Nacional de ResĂduos SĂłlidos
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